Part One discusses written sources, theories regarding migration, and environmental change in the first millennium AD. In Part Two, archaeological sources relating to Central Europe in the Migration Period are analysed, while Part Three is devoted to new discoveries between the Oder and the Vistula, including traces of Germanic settlement in northern Poland in the early seventh century. In Part Four, evidence for cultural and settlement changes in neighbouring areas is characterized in a comparative light.
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Edited by Aleksander Bursche, John Hines and Anna Zapolska
Part One discusses written sources, theories regarding migration, and environmental change in the first millennium AD. In Part Two, archaeological sources relating to Central Europe in the Migration Period are analysed, while Part Three is devoted to new discoveries between the Oder and the Vistula, including traces of Germanic settlement in northern Poland in the early seventh century. In Part Four, evidence for cultural and settlement changes in neighbouring areas is characterized in a comparative light.
The book deals in the first volume with 298 species and contains descriptions of 99 new notodontid taxa. A second volume will treat with the remaining 160 species and include also a comprehensive biogeographic analysis.
Ante Vujić, Martin Speight, Michael Edwin de Courcy Williams, Santos Rojo, Gunilla Ståhls, Snežana Radenković, Laura Likov, Marija Miličić, Celeste Pérez-Bañón, Steven Falk and Theodora Petanidou
The Atlas is a concise presentation of all 418 hoverfly species for Greece known so far. The species are documented with photos and distribution GIS-maps and they are preceded by a general introduction on the hoverflies and Greek nature, and a generic key.
The Atlas of the Hoverflies of Greece is a handbook for insect aficionados, students and teachers, everyone interested in nature, and managers and conservationists aiming at raising public awareness of a nature nowadays threatened more than ever.
Mihaela C. Ion, Adela E. Puha, Tudor Suciu and Lucian Pârvulescu
Animals that face unusual situations react instinctively in order to efficiently adapt to changes in the environment. Persistence leads training and learning the developed solution, which can then be applied to similar challenges in the future. We experimented on adult narrow-clawed crayfish extracted from both lentic and lotic habitats. We proved that the latter were more prone to grabbing objects during acute exposure to water currents. Chronic exposure of specimens from lentic habitat to water currents led to intense training in clumping activity, gripping quickly to adherent side objects regardless of the origin (natural or artificial). The behaviour was significantly reduced after the trained specimens were returned to an environment without water currents for a four-week period. The results suggest that crayfish can learn a solution when faced with a disturbance; once the disturbance disappeared, the trained response was no longer needed and lost.
Diego Bueno-Villafañe, Andrea Caballlero-Gini, Marcela Ferreira, Flavia Netto, Danilo Fernández Ríos and Francisco Brusquetti
Ontogenetic colour change (OCC) is defined as the progressive and non-reversible process of changes in colouration of organisms associated with their development. Among the many vertebrate groups, amphibians are particularly impressive for their strikingly wide variety of colours, colour patterns, and signals, whose evolutionary and ecological significance have been poorly studied. Elachistocleis comprises 18 species currently separated into two main groups based on their ventral colour pattern: one immaculate and the other with specks and/or colour patches. Elachistocleis haroi is a small-sized species within the immaculate venter group, distributed in the Yungas and Dry Chaco ecoregions from which little information is known. In a comprehensive sampling of post-metamorphic individuals of E. haroi at different stages of development we identified a significant variation in ventral colour pattern, which could denote a progressive filling of yellow colour according to an ontogenetic pattern. To test this hypothesis, we analysed 39 post-metamorphic individuals of E. haroi at different stages of development with imaging procedures. We found that yellow spots and their intensity are significantly related to snout-vent length, as major expansion of colour on the sides, gular region and male chest, as almost no development on the belly. We briefly discuss our findings in relation to sexual display and predation avoidance. To our knowledge, this is the first analysis of post-metamorphic OCC in ventral colouration in the genus Elachistocleis.
Laura M. Bolt, Dorian G. Russell, Elizabeth M.C. Coggeshall, Zachary S. Jacobson, Carrie Merrigan-Johnson and Amy L. Schreier
The ways that forest edges may affect animal vocalization behaviour are poorly understood. We investigated the effects of various types of edge habitat on the loud calls (howls) of a folivorous-frugivorous primate species, Alouatta palliata, with reference to the ecological resource defence hypothesis, which predicts that males howl to defend vegetation resources. We tested this hypothesis across four forest zones — interior, riparian, anthropogenic, and combined forest edges — in a riparian forest fragment in Costa Rica. We predicted vegetation and howling would differ between forest zones, with riparian and interior zones showing the highest values and anthropogenic edge the lowest. Our results indicated that vegetation was richer and howling longer in riparian and interior zones compared to combined and anthropogenic edges, supporting the resource defence hypothesis and providing some of the first evidence in animal communication scholarship for differences in behavioural edge effects between natural riparian and anthropogenic edges.
Maliheh Pirayesh Shirazinejad, Mansour Aliabadian and Omid Mirshamsi
The white wagtail (Motacilla alba) species complex with its distinctive plumage in separate geographical areas can serve as a model to test evolutionary hypotheses. Its extensive variety in plumage, despite the genetic similarity between taxa, and the evolutionary events connected to this variety are poorly understood. Therefore we sampled in the breeding range of the white wagtail: 338 individuals were analyzed from 74 areas in the Palearctic and Mediterranean. We studied the white wagtail complex based on two mitochondrial DNA markers to make inferences about the evolutionary history. Our phylogenetic trees highlight mtDNA sequences (ND2, CR), and one nuclear marker (CHD1Z), which partly correspond to earlier described clades: the northern Palearctic (clade N); eastern and central Asia (clade SE); south-western Asia west to the British Isles (clade SW); and Morocco (clade M). The divergence of all clades occurred during the Pleistocene. We also used ecological niche modelling for three genetic lineages (excluding clade M); results showed congruence between niche and phylogenetic divergence in these clades. The results of the white wagtail ancestral area reconstruction showed the influence of dispersal on the distribution and divergence of this complex species. The most important vicariance event for the white wagtail complex may have been caused by the Gobi and Taklamakan deserts. We conclude that the ancestral area of the white wagtail complex was probably in the Mediterranean, with its geography having a considerable effect on speciation processes.
Oksana A. Korzhavina, Bert W. Hoeksema and Viatcheslav N. Ivanenko
This review of copepod crustaceans associated with reef-dwelling cnidarians, sponges and echinoderms of the Greater Caribbean is based on published records, systematically arranged by the classification of symbiotic copepods and their hosts, sampling sites, coordinates, depth and date of sampling, literature sources, and three recent surveys (Cuba, St. Eustatius in the Eastern Caribbean and Curaçao in the Southern Caribbean). This resulted in totals of 532 records of 115 species of symbiotic copepods (47 genera, 17 families, three orders) hosted by 80 species of invertebrates, representing scleractinians (47%), octocorals (9%), echinoderms (3%), and sponges (1%). Among ten Caribbean ecoregions, the Greater Antilles (with 64 species of symbiotic copepods) as well as the Southern and Eastern Caribbean (with 46 and 17 species of copepods, respectively) are the most studied and best represented, whereas only six species of copepods are known from Bermuda, one from Southwestern Caribbean and none from the Gulf of Mexico. The absence of poecilostomatoid copepods (Anchimolgidae, Rhynchomolgidae and Xarifidae) on Caribbean stony corals as noted by Stock (1988) is confirmed. The results indicate that the diversity and ecology of Caribbean symbiotic copepods are still poorly investigated.
Tomáš Němec and Michal Horsák
Shell formation is the main defensive strategy against predation for the majority of snails. Therefore, various predators have had to develop a variety of techniques how to overcome this barrier. As shells can persist in a calcium-rich environment for a long time, specific external or internal traces on shells left by predators indicate whether and who killed the snail. Based on litter samples collected at 30 sites of five different habitat types, the intensity and type of predation were assessed. The minimal predation rate varied between 0.0 and 21%, with an average of 8%. The highest rate was observed at limestone steppes, on average 15%. Beetles were found to be the most common predators of snails; however, predation by snails was more common in calcareous fens. Predation by some vertebrates and dipteran flies was also recognised. To test the role of mouth barriers as a means to reduce predation by carabid beetles that break the shell from an aperture, we analysed the predation rate separately on adult and juvenile shells using 24 populations of the steppe snail Granaria frumentum (Draparnaud, 1801). As expected, carabid beetles chiefly preferred juveniles compared to adult shells (Wilcoxon test, p < 0.001). On the contrary, the parasitoid fly Pherbellia limbata (Meigen, 1830) and Drilus beetles preferred adults. We found that predation by carabid beetles positively increased with prey abundance (R2 = 42.8%, p = 0.021), while no relation was observed for the parasitoid (p = 0.703), likely due to their feeding specialisation.
Miguel A. Meca, Pilar Drake and Daniel Martin
The polychaete Oxydromus okupa lives in association with the bivalves Scrobicularia plana and Macomopsis pellucida in the intertidal of Río San Pedro (CI = Cádiz Intertidal) and adjacent to CHipiona (CH) harbour, and in the subtidal of the Bay of Cádiz (CS = Cádiz Subtidal). We analyse these populations morphometrically, ecologically (including infestation characteristics) and genetically (intertidal populations, 16S and ITS-1 genes). We consider “host”, “environment” and the combined “host and environment” as possible factors of interpopulation variability. Morphometry revealed three well-defined clusters for CI, CH and CS, showing intergroup phenotypic differences ranging from 35 to 50%. Hosts shell lengths ranged between 26 and 36 mm for S. plana and 20 and 28 mm for M. pellucida. The infestation of small M. pellucida by juvenile O. okupa suggests they show an active size segregation behaviour. The intertidal seems to be less favourable (infestation rate <25% vs. up to 65% in the subtidal), and did not show recent bottleneck events. Overall, CI and CH were genetically homogeneous, but showed a significant divergence (one dominant haplotype in each host species), suggesting host shift as being a soft barrier to gene flow. Most characters related with host-entering varied among populations, suggesting symbiotic behaviour to play a key role in reducing panmixia and leading to the initial phases of a speciation process in sympatric symbiotic populations. Polyxeny and symbiotic behaviour in O. okupa seem thus to be underlying mechanisms contributing to its great phenotypic variety, marked ecological differences, and genetic divergence.
Giacinta Angela Stocchino, Ronald Sluys, Abdel Halim Harrath, Lamjed Mansour and Renata Manconi
Invasions of alien species form one of the major threats to global biodiversity. Among planarian flatworms many species are known to be invasive, in several cases strongly affecting local ecosystems. Therefore, a detailed knowledge on the biology of an invasive species is of utmost importance for understanding the process of invasion, the cause of its success, and the subsequent ecological impact on native species. This paper provides new information on the biology of introduced populations of the freshwater flatworm Girardia tigrina (Girard, 1850) from Europe. This species is a native of the Nearctic Region that was accidentally introduced into Europe in the 1920s. Since then, numerous records across the European continent bear witness of the invasiveness of this species, although only a few studies focused on the biology of the introduced populations. We report on the morphology of sexualized individuals from a fissiparous Italian population, representing the second record of spontaneous sexualization of fissiparous individuals in this species. A detailed morphological account of the reproductive apparatus of these ex-fissiparous animals is presented. Our results increased the number of morphological groups previously recognized for European populations of G. tigrina, thus corroborating the hypothesis on multiple independent introductions to this continent. Karyological results obtained from our fissiparous Italian individuals revealed a constant diploid chromosome complement of sixteen chromosomes. Further, we document the marked intraspecific variation in several morphological features of this species.
Cessa Rauch, Bert W. Hoeksema, Bambang Hermanto and Charles H.J.M. Fransen
Most marine palaemonid shrimp species live in symbiosis with invertebrates of various phyla. These associations range from weak epibiosis to obligatory endosymbiosis and from restricted commensalism to semi-parasitism. On coral reefs, such symbiotic shrimps can contribute to the associated biodiversity of reef corals. Among the host taxa, mushroom corals (Cnidaria: Anthozoa: Fungiidae) are known to harbour various groups of symbionts, including shrimps. Some but not all of these associated species are host-specific. Because data on the host specificity of shrimps on mushroom corals are scarce, shrimp species of the genus Periclimenes were collected from mushroom corals during fieldwork in Lembeh Strait, North Sulawesi, Indonesia. Using molecular (COI barcoding gene) and morphological methods, three species of Periclimenes were identified: P. diversipes, P. watamuae and a species new to science, P. subcorallum sp. nov., described herein. Their host specificity was variable, with eight, three and two fungiid host records, respectively. It is concluded that shrimp species of the genus Periclimenes show much overlap in their host choice and that particular morphological traits in the host species appear to play a more important role than phylogenetic affinities within the host group.
Gerrit Potkamp and Charles H.J.M. Fransen
Over the last century, a large body of literature emerged on mechanisms driving speciation. Most of the research into these questions focussed on terrestrial systems, while research in marine systems lagged behind. Here, we review the population genetic mechanisms and geographic context of 33 potential cases of speciation with gene flow in the marine realm, using six criteria inferred from theoretical models of speciation. Speciation with gene flow occurs in a wide range of marine taxa. Single traits, which induce assortative mating and are subjected to disruptive selection, such as differences in host-associations in invertebrates or colour pattern in tropical fish, are potentially responsible for a decrease in gene flow and may be driving divergence in the majority of cases. However, much remains unknown, and with the current knowledge, the frequency of ecological speciation with gene flow in marine systems remains difficult to estimate. Standardized, generally applicable statistical methods, explicitly testing different hypotheses of speciation, are, going forward, required to confidently infer speciation with gene flow.
Edited by Martin Dabrowski, Judith Wolf and Karlies Abmeier
Editorial-board Arnd Küppers, Christian Müller, Joachim Wiemeyer and Marianne Heimbach-Steins
In diesem Sammelband der Reihe „Sozialethik konkret“ wird die vielschichtige Problematik einer globalen und gerechten Umweltpolitik aufgegriffen und aus der Sicht unterschiedlicher wissenschaftlicher Disziplinen diskutiert. Im Diskurs der verschiedenen Wissenschaften sollen eine ausgewogene Beurteilung der Thematik erreicht, Vorschläge zur konkreten Gestaltung von Reformprozessen und konkrete Ausgestaltungen der Umweltpolitik erarbeitet und offene und weiterführende Fragestellungen identifiziert werden.
Piotr Gąsiorek, Daniel Stec, Witold Morek and Łukasz Michalczyk
Isohypsibioidea are most likely the most basally branching evolutionary lineage of eutardigrades. Despite being second largest eutardigrade order, phylogenetic relationships and systematics within this group remain largely unresolved. Broad taxon sampling, especially within one of the most speciose tardigrade genera, Isohypsibius Thulin, 1928, and application of both comparative morphological methods (light contrast and scanning electron microscopy imaging of external morphology and buccal apparatuses) and phylogenetic framework (18S + 28S rRNA sequences) resulted in the most comprehensive study devoted to this order so far. Two new families are erected from the currently recognised family Isohypsibiidae: Doryphoribiidae fam. nov., comprising all aquatic isohypsibioids and some terrestrial isohypsibioid taxa equipped with the ventral lamina; and Halobiotidae fam. nov., secondarily marine eutardigrades with unique adaptations to sea environment. We also split Isohypsibius into four genera to accommodate phylogenetic, morphological and ecological variation within the genus: terrestrial Isohypsibius s.s. (Isohypsibiidae), with smooth or sculptured cuticle but without gibbosities; terrestrial Dianea gen. nov. (Isohypsibiidae), with small and pointy gibbosities; terrestrial Ursulinius gen. nov. (Isohypsibiidae), with large and rounded gibbosities; and aquatic Grevenius gen. nov. (Doryphoribiidae fam. nov.), typically with rough cuticle and claws with branches of very similar heigths. Claw morphology is reviewed and, for the first time, shown to encompass a number of morphotypes that correlate with clades recovered in the molecular analysis. The anatomy of pharynx and cuticle are also shown to be of high value in distinguishing supraspecific taxa in Isohypsibioidea. Taxonomy of all isohypsibioid families and genera is discussed, with special emphasis on the newly erected entities. Finally, a dychotomous diagnostic key to all currently recognised isohypsibioid families and genera is provided.
Bernhard A. Huber and Anne Chao
Ratio-like approaches for estimating global species richness have been criticised for their unjustified extrapolation from regional to global patterns. Here we explore the use of cumulative percentages of ‘new’ (i.e., not formally described) species over large geographic areas (‘megatransects’) as a means to overcome this problem. In addition, we take into account undetected species and illustrate these combined methods by applying them to a family of spiders (Pholcidae) that currently contains some 1,700 described species. The raw global cumulative percentage of new species (‘new’ as of the end of 2008, when 1,001 species were formally described) is 75.1%, and is relatively constant across large biogeographic regions. Undetected species are estimated using the Chao2 estimator based on species incidence data (date by species and locality by species matrices). The estimated percentage of new species based on the date by species matrices is 76.0% with an estimated standard error (s.e.) of 2.6%. This leads to an estimated global species richness of about 4,200 with a 95% confidence interval of (3,300, 5,000). The corresponding values based on locality by species matrices are 84.2% (s.e. 3.0%) and 6,300 with a 95% confidence interval of (4,000, 8,600). Our results suggest that the currently known 1,700 species of Pholcidae may represent no more than about 25–40% of the total species richness. The impact of further biasing factors like geography, species size and distribution, cryptic species, and model assumptions needs to be explored.
Antonio Archidona-Yuste, Carolina Cantalapiedra-Navarrete, Pablo Castillo and Juan E. Palomares-Rius
The genus Longidorus constitutes a large group of approximately 170 species of plant-ectoparasitic nematodes that are polyphagous and distributed almost worldwide. Some of the species of this genus are vectors of plant viruses. Species discrimination in Longidorus is difficult because the morphology is very conservative, and morphometric characters often overlap, leading to potential misidentification. Integrative taxonomy, based on the combination of molecular analyses with morphology, is a useful and necessary approach in Longidorus species identification. In Spain from 2014 to 2017, we conducted nematode surveys among cultivated and wild plants, from which we identified 13 populations of Longidorus, two of which appeared to represent new species and are described herein as L. iliturgiensis sp. nov. and L. pacensis sp. nov., and 11 populations belonging to eight known species: L. africanus, L. baeticus, L. carpetanensis, L. fasciatus, L. nevesi, L. cf. olegi, L. pini, and L. vallensis. Three species are new geographical records for Spain (L. nevesi, L. cf. olegi, and L. africanus). We report molecular data for L. nevesi, L. cf. olegi, L. carpetanensis and L. pini for the first time. Additionally, we describe the males of L. pini and the juveniles of L. cf. olegi.
Yee Wah Lau, Frank R. Stokvis, Yukimitsu Imahara and James D. Reimer
Stoloniferan octocorals (Cnidaria: Anthozoa: Octocorallia: Alcyonacea) are a relatively unexplored fauna in the Ryukyus (southern Japan), known to be a tropical marine region of high biodiversity and endemism of species. Specimens of stoloniferous octocorals were collected during fieldwork along the coasts of two islands (Okinawa and Iriomote) in the Okinawa Prefecture. Despite their phenotypic polyp variation, this study shows their morphological and molecular uniqueness, leading to the description of a new genus with a single species: Hanabira yukibana, gen. nov., sp. nov. They are placed within the Clavulariidae and form a sister clade basally to the genus Knopia Alderslade & McFadden, 2007 and species of Clavularia Blainville, 1830. The polyps of this new species show morphological variation in both shape and sclerite density, but there is conformity in the typical overall petal shaped tentacles, which have fused pinnules (pseudopinnules). Depending on the densities of their sclerites and their photosynthetic endosymbiotic algae (zooxanthellae) of the family Symbiodiniaceae, there is a characteristic sheen present in the tentacles. Moreover, the zooxanthellae hosted by our specimens form a clear, small-scale biogeographic pattern; all H. yukibana specimens from Okinawa Island contained zooxanthellae of the genus Cladocopium Lajeunesse & H.J. Jeong, 2018 (= former Symbiodinium ‘Clade C’) and all specimens from Iriomote Island hosted zooxanthellae of the genus Durusdinium LaJeunesse, 2018 (= former Symbiodinium ‘Clade D’). These results show the potential for variation among the Symbiodiniaceae floras within octocorals, something that has not yet been investigated for the large majority of zooxanthellate octocoral species.
(Myrmecozelinae, Perissomasticinae, Tineinae, Hieroxestinae, Teichobiinae and Stathmopolitinae)
Additional records are listed for species treated in volume 7, as well as two taxa which were overlooked before and nine new species are listed.
Hongliang Lu, Yingchao Hu, Shuran Li, Wei Dang and Yongpu Zhang
Temperature is a crucial environmental factor that can strongly impact animal physiology. Here, we acclimated hatchling of Asian yellow pond turtles (Mauremys mutica) to one of two different temperatures (25 or 30°C) for four weeks to determine temperature acclimation effects on their physiology. All four measured physiological variables (righting time, resting metabolic rate, critical thermal minimum and critical thermal maximum) were significantly affected by temperature acclimation. Turtles acclimated to 25°C righted themselves more slowly and had a lower mean metabolic rate than 30°C-acclimated turtles. Turtles acclimated to 25°C were more resistant to low temperatures, but less resistant to high temperatures than 30°C-acclimated turtles, as measured by critical thermal limits. The thermal resistance range (i.e., the difference between critical thermal minimum and maximum) did not differ between the two acclimation groups. Compared with other semi-aquatic turtles, M. mutica had relatively higher acclimation response ratios for its critical thermal minimum and critical thermal maximum. Our results indicate that acclimation to relatively moderate temperatures could also produce significant responses in the thermal physiology of turtles.
Irelis Bignotte-Giró, Ansel Fong G. and Germán M. López-Iborra
Acoustic segregation is a way to reduce competition and allows for species coexistence within anuran communities. Thus, separation in at least one acoustic niche dimension is expected, which also contributes to achieving effective communication among frogs. Here we studied an assemblage of five terrestrial egg-laying anuran species, all in the genus Eleutherodactylus, in a montane rainforest in eastern Cuba. Our aim was to determine if partitioning exists between these species in any dimension (time, signal frequency or space) of the acoustic niche. The studied assemblage had the following characteristics: (1) there was one diurnal species, two species with calling activity throughout the day and two species that call at night; (2) only two species overlapped in call frequencies and most had different calls, both in terms of dominant frequencies and in temporal characteristics; and (3) males of the species that overlapped in vocalizing time or signal frequency used different calling microhabitats or heights. This study provides evidence for the acoustic niche hypothesis in anurans, showing low probabilities of interference in sound communication among these frogs. The five species were separated in at least one of the three acoustic dimensions (calling time, frequency and site) as it occurs in mainland communities with more sympatric species of several genera. Conversely, species in single-genus communities studied in Puerto Rico overlapped completely in calling times. This seems to be due to the higher number of sympatric species at our site.
Ilya A. Volodin, Olga V. Sibiryakova, Natalia V. Soldatova and Elena V. Volodina
Relationships between individualization and the acoustics of contact calls in ungulate mother and young are different between taxa. We compared the acoustic variables and individuality of adult female and neonate goitred gazelles Gazella subgutturosa. Discriminant function analysis based on six acoustic variables of nasal (closed-mouth) contact calls similarly accurately classified calls to neonate and adult individuals in spite of the prominent differences in the acoustic resonances (formants) and the mean fundamental frequency of their calls. In addition, we found prominent differences in duration, mean fundamental frequency and frequencies of the first four formants between nasal and oral (open-mouth) contact calls within and between adult and neonate age-classes. We discuss the effects on the acoustics of call production mode (oral versus nasal) and the relationship of acoustic differences and individuality in mother and young contact calls across species of ruminants (Bovidae and Cervidae).
William G. Eberhard
Orb web construction was originally thought to be highly stereotyped, but adaptive flexibility is now well established in several aspects. This study reviews published data on one behavioural cue and presents new data on flexibility in experimentally modified and control webs of Zosis geniculata and Uloborus diversus. By occasionally ignoring this cue temporarily, spiders gained access to otherwise inaccessible portions of their webs. I discuss three hypotheses concerning the mechanism that resulted in this flexibility. Several types of evidence argue against the hypothesis that the adjustments were pre-programmed: substantial variation in the contexts when adjustments occurred; substantial variation in details of the adjustments; and rarity of the contexts that require adjustments in nature. Lack of plausible links between behavioural decisions and payoffs from prey capture argue against a second, learning hypothesis. By elimination, this flexibility may require a third type of explanation that includes more elaborate cognitive processes.
Yoonhyuk Bae, Sungsik Kong, Yoonjung Yi, Yikweon Jang and Amaël Borzée
Anthropogenic modifications of the environment have clear negative impacts on species. These effects may reach a higher magnitude in highly altered habitats, for example in wetlands transformed into rice paddies. This is the case for the amphibian species of the genus Hynobius in the Republic of Korea, which originally breed in slow streams and valleys. However, a comparatively high proportion of the natural breeding sites used by the species in the lowlands has been transformed into rice paddies. Here, we assessed whether anthropogenic modification of wetlands leads to an additional threat to breeding Hynobius spp. in the form of increased vulnerability of their egg clutches to loach predators (Misgurnus species) in such modified habitats. We conducted weekly occurrence surveys at 27 randomly selected sites in the Republic of Korea and recorded the following information: type of site (natural versus agricultural), air temperature, water conductivity, moon phase and predation by Misgurnus sp. Our results reveal, for the first time, cases of predation of Hynobius spp. eggs by Misgurnus loaches. We also show that the risk of predation was higher in agricultural sites in comparison to natural sites. In conclusion, we demonstrate the increased predation risk of Hynobius spp. eggs by Misgurnus sp. at anthropogenically disturbed sites, and thus a new type of threat to Hynobius populations. This new type of threat may, however, be due to expansion of the breeding habitats following human disruptions to landscapes. We therefore call for the development of mitigating measures to wetland modifications.
Dena J. Clink, Allison R. Lau and Karen L. Bales
Duets in pair-bonding primates serve as a primary mode of communication between pairs, and duets may provide cues to conspecifics regarding the calling individual or pair. Here, we test the hypothesis that pulse elements in coppery titi monkey duets vary with condition and identity of the caller. We predicted that pulse elements would vary with age, sex, or pair-bond length. We estimated pulse rate and duration for 378 pulse elements from the duets of 74 captive titi monkeys (Plecturocebus cupreus). We found inter-individual variation in both features, and evidence for vocal convergence among pair mates in pulse rate. Age was the best predictor of pulse rate, and pulse rate decreased with age. Age and pair-bond length reliably predicted pulse duration. Our results suggest that variation in titi monkey duets reflects differences in caller condition and pair identity, and contribute to growing evidence for vocal plasticity in nonhuman primates.
Nurettin Beşer, Çetin Ilgaz, Yusuf Kumlutaş, Aziz Avcı, Kamil Candan and Nazan Üzüm
Within reptiles, lizards cover less area across the globe than snakes do. One out of every seven known species of lizards in the world is found only in its type locality. Acanthodactylus harranensis Baran, Kumlutaş, Lanza, Sindaco, Ilgaz, Avcı & Crucitti, 2005, is one of these species. It is an endemic lizard species in Turkey with a very small area of occupancy and is listed in the critically endangered category (CR) by the IUCN. Here we document the age structure and body size of A. harranensis using skeletochronological methods for the first time and aim to point out current problems and contribute to an understanding of its demography. The mean age of males was found to be significantly higher than that of females. The maximum life span was 10 years in males while it was 9 years in females. The 8-year-old age group contained a higher number of individuals than any other age group. The mean snout-vent length of specimens was not significantly different between the sexes. As in many other lizards, A. harranensis exhibits a low-level male-biased sexual dimorphism. Acanthodactylus harranensis also displayed a considerably bigger body size than other studied lacertids from Şanlıurfa province. The data presented in this study may contribute to future conservation efforts for this endangered species.
Melita Vamberger, Cäcilia Spitzweg, Anslem de Silva, Rafaqat Masroor, Peter Praschag and Uwe Fritz
Geochelone elegans is one of the most heavily traded tortoise species of the world, and confiscated tortoises are frequently released into the wild, without knowledge about their origin. Using for the first time samples from Pakistan and Sri Lanka, we examined phylogeographic differentiation of G. elegans using 2289 bp of mitochondrial DNA. We found weak intraspecific differentiation without a clear geographic pattern. We suggest that natural phylogeographic differentiation may have been already destroyed by massive releases of confiscated non-native tortoises. The presence of two distinct clades on Sri Lanka, however, could also be the result of a natural range expansion of a mainland lineage into the distribution range of a lineage endemic to Sri Lanka during Pleistocene low sea level stands. We propose that a systematic screening of the genetic differentiation of wild G. elegans should be conducted across its entire distribution range to provide a sound basis for the relocation of confiscated tortoises.
Li Zhao, Chun Lan Mai, Guo Hou Liu and Wen Bo Liao
Phenotypic flexibility of morphological and physiological traits within species is a common phenomenon across animal taxa. Hesse’s rule predicts that the size of an organ should exhibit an increase with increasing altitude along environmental gradients due to changes in oxygen supply and energy demands. Here, we test the prediction of Hesse’s rule by investigating geographical variation in the relative size of organs (i.e., heart, lungs, liver, and kidneys) across ten populations of Bufo andrewsi along an environmental gradient. We found that the relative size of these four specific organs did not increase with altitude or latitude across all populations. We also did not find that the relative size of the organs increased with increasing altitude among six populations located at a similar latitude and longitude, which is inconsistent with Hesse’s rule. Our findings suggest that oxygen supply and energy demands do not necessarily affect variation in organ size among populations.
Zhi Li, Yan Ma, Xuan Liu, Yi Li and Fangyin Dai
Antimicrobial peptides (AMPs) are a type of small molecular proteins that play a vital role in the resistance to alien pathogens. AMPs are widespread in bacteria, archaea, protists, fungi, plants and animals. AMPs have a broad spectrum of antimicrobial activities and they rarely induce bacteria resistance; thus, they are thought to be good candidates for antibiotics in clinical practice. Recently, AMPs are increasingly attracting attention because of their outstanding features and functions. In addition to their known antibacterial properties, some kinds of AMPs have also been reported to have antiviral, anticancer, antiparasitic, and antioxidant activity. In this review, we introduce the diversity of AMPs, including their structure, function and related mechanisms. We focus primarily on recent studies of silkworm AMPs and summarize their classification, activities and possible mechanisms. Finally, based on the review, probable directions and perspectives for studies of the AMPs of silkworm are discussed and proposed.
David M. Delaney
The use of defensive behaviors to avoid predation increases the likelihood of survival. Snake species have evolved numerous and diverse antipredatory behaviors to fit a variety of natural histories. Understanding how snakes react to simulated predation events can help us understand their ecology. I conducted behavioral trials on 11 colubrid and dipsadid species (
Peter Mikula, Emma Nelson, Piotr Tryjanowski and Tomáš Albrecht
Escape behaviour is a common antipredator strategy of lizards. Here, we studied the effect of several variables predicted to have a potential effect on escape behaviour of lizards. Specifically, we measured the effects of starting distance (SD), distance to cover, sex–age and the observer’s head orientation on flight initiation distance (FID) in the common agama Agama agama. Agamas were approached in urban localities in Limbe city, Cameroon, where they were habituated to the presence of humans. We found no association between FID and SD, but individuals closer to potential cover had shorter FID than individuals farther from a refuge. Juveniles escaped later than adults, but no significant differences were found in the FID between adult males and females. Head direction of the approaching observer had no effect on FID. This is, to the best of our knowledge, the first study investigating factors affecting FID in common agamas, extending our knowledge of risk-related behaviour in lizards of the Old World tropics.
Uschi Wischhoff, Fernando Marques-Santos, Giselle Bonetti, Lilian T. Manica, James J. Roper and Marcos Rodrigues
How are personalities maintained in wild animal populations? A possible mechanism is the existence of trade-offs between fitness components (survival and reproductive success) among behavioural types. We investigated this trade-off in white-rumped swallows (Tachycineta leucorrhoa) by capturing adults and monitoring their reproduction over time. We focused on the personality trait of nest defence against a human. We found that swallows with different levels of nest defence had similar probability to return from migration between two years (a proxy for survival). In one year, swallows that defended their nests more boldly were also more likely to succeed. However, nest defence was not linked to nestling weight or number of fledglings. Thus, we found no evidence of a trade-off between fitness components. It is possible that the investigated relationships become relevant only in extreme years that severely alter the costs and benefits of this behaviour.
Zoe L. Fraser, Ross M. Culloch and Sean D. Twiss
Time-activity budgets are fundamental to behavioural studies, allowing examination of how individuals allocate their time, and potentially energy, and how these patterns vary spatially and temporally and in relation to habitat, individual identity, sex, social status and levels of anthropogenic disturbance. Direct observations of animal behaviour, especially in the wild, are often limited to daylight hours; therefore, many activity budgets relate to diurnal activity only, or assumptions are made about nocturnal activity. Activity budgets have been a key component of many behavioural and energetics studies of breeding grey seals (Halichoerus grypus, Fabricius, 1791), and yet very little is known about nocturnal activity of grey seals, and a general, implicit assumption of no significant change from day to night seems to pervade the literature. Here we use a combination of high resolution digital video and thermal imaging video camera to follow known individual grey seal mothers from day into night to examine activity patterns during lactation. We show distinct differences in nocturnal activity budgets relative to diurnal activity budgets. Mothers spent significantly more time resting with a reduction of time spent in the alert and comfort move behavioural categories during nocturnal periods. It is clear that diurnal time-activity patterns of breeding female grey seals cannot be extrapolated to represent activity across a 24-hour cycle. These considerations are particularly critical in studies that aim to use time-activity budgets as proxies for energy budgets.
Giovanne A. Ferreira, Eduardo Nakano-Oliveira, Artur Andriolo and Gelson Genaro
The presence of domestic cats in natural areas is considered one of the main reasons for species loss, especially on islands and among native small non-volant mammals, birds and reptiles. However, in this study, we detected values opposite to those expected for species richness, abundance, and diversity among different areas when considering the presence or absence and density of these felines. We also observed that in the evaluated environments, prey availability did not influence consumption of small mammal species. Our results reinforce the theory of domestic cats’ behaviour as being opportunistic and generalist predators. In addition, we only recorded the presence of exotic species in the faeces of cats; that is, we did not capture exotic species in the traps. The close relationship between these exotic species and anthropogenic environments indicates that felines are likely hunting in areas close to the homes where they live. Assessing the impact of predation by domestic cats on native fauna is important for the development and implementation of strategic resource management and to minimize long-term impacts.
Nobuyuki Kutsukake, Migaku Teramoto, Seijiro Honma, Yusuke Mori, Koki Ikeda, Rain Yamamoto, Takafumi Ishida and Toshikazu Hasegawa
Group housing of socially-deprived individuals facilitates welfare and socialisation of primates. Here, we studied behavioural and hormonal changes in the course of group formation among nine male chimpanzees, Pan troglodytes. Aggression, reassurance, and grooming were observed in various dyads during group formation. The pattern of fluctuations in salivary cortisol level changed through the process of group formation, with particularly high cortisol levels immediately after group interactions relative to other sampling timings during group formation. Salivary testosterone levels were unaffected by the process of group formation or sampling time. These results suggested that a combination of behavioural observation and hormonal analyses is a powerful approach to assess the impact of group formation.
Shivaji H. Thube, Gagana Kumar Mahapatro, Chandrika Mohan, Thava Prakasa Pandian R., Elain Apshara and Jose C.T.
Cocoa (Theobroma cacao L.) is an important beverage crop and commercially grown as a plantation crop. With the changing climate, the tea mosquito bug species complex, viz., Helopeltis theivora, H. bradyi and H. antonii, is emerging as a major threat to cocoa cultivation in India. Among the species of this complex H. theivora is responsible for causing considerable damage. The present investigations were carried out to find a weak link in the life cycle of H. theivora so it can be managed effectively. Specimens of the tea mosquito bug were found to first appear during the first week of September in South India. Helopeltis theivora requires on average 29.28 days to complete its life cycle on cocoa. The highest level of natural mortality was recorded in the first-instar nymph. The total developmental period of the fifth-instar nymph was significantly longer than that for the other nymphal instars. The sex ratio reflects that the population is highly female-biased, which may contribute to the dominant nature of this species in the cocoa ecosystem. Observation of the feeding and oviposition behavior of H. theivora revealed that the insect prefers to feed and oviposit on developing pods rather than on leaves and shoots. Analysis of the species distribution of tea mosquito bug at different elevations revealed that cocoa gardens situated less than 300 meter above mean sea level are dominated by H. theivora, whereas gardens situated more than 300 meter above mean sea level are dominated by H. bradyi. This separation of species across elevation may be driven either by abiotic or biotic factors.
Megan L. Lambert, Ivo Jacobs, Mathias Osvath and Auguste M.P. von Bayern
The last several decades of research on avian cognition have revealed surprising parallels between the abilities of birds — most notably corvids — and great apes. Parrots, albeit far less studied, are cited alongside corvids as “feathered apes”, but are these two taxa really that similar cognitively? In this review we aim to take a step back and present the broader picture, focusing on areas where there is now data from both parrots and corvids to facilitate first comparisons on a somewhat wider scale. By charting these birds’ performance in cognitive tasks, in many of which corvids perform on par with primates, we hope to highlight understudied areas and promising directions for future research. In reviewing the literature, the general pattern that emerges shows that different corvid and parrot species indeed perform similarly in a range of cognitive tasks to the extent that one may call them “feathered apes”.
Robby Marcel Drechsler and Juan Salvador Monrós
We calculated growth rate for the spiny-footed lizard (Acanthodactylus erythrurus) inhabiting coastal eastern Spain from long-term mark-recapture data. Growth curves differ between sexes, with males growing faster than females and achieving larger size maximums. In this population each sex reaches maturity at about 300 days of age, approximately 34% faster than males, and 28% faster than females studied in a population further south and west in Iberia. Our logarithmic growth model has an accuracy of 96.8% and high statistical significance (
Anna Najbar, Agnieszka Konowalik, Konrad Halupka, Bartłomiej Najbar and Maria Ogielska
The fire salamander Salamandra salamandra is a widespread taxon in Europe, exhibiting great intraspecific diversity in phenotype and life history traits across its geographical distribution. Here, we studied body size, sexual dimorphism, age, growth rate and condition of fire salamanders from the north-eastern margin of its range. In total, 2,102 individuals from 23 populations representing the Polish parts of the Sudetes and the Carpathian Mountains were sampled between 2004 and 2016. Body traits and age showed significant differences between the western (the Sudetes) and eastern (the Carpathians) groups of populations. Salamanders from the Carpathians tended to be longer, heavier and older. Female-biased sexual size dimorphism was found only in the Carpathians. Body condition at the beginning of the season was poor, then increased to reach a peak in early June, and deteriorated toward the end of the season. Age estimated by skeletochronology on phalangeal bones ranged from 2 to 16 years in both females and males, with the highest share of 7- to 9-year-old individuals. Age of juveniles ranged from 1 to 5 years in the Sudetes and from 1 to 4 years in the Carpathians. Growth curves (fitted using von Bertalanffy’s model) were asymptotic throughout the individual lifespans, but exhibited differences between sexes and mountain ranges. Altitude did not explain differences in characteristics of populations living in the two mountain ranges, but these differences most probably resulted from habitat quality (better in the Carpathians) and adverse human impact (higher in the Sudetes).
Chun Lan Mai and Wen Bo Liao
Selection pressure is an important force in shaping the evolution of vertebrate brain size among populations within species as well as between species. The evolution of brain size is tightly linked to natural and sexual selection, and life-history traits. In particular, increased environmental stress, intensity of sexual selection, and slower life history usually result in enlarged brains. However, although previous studies have addressed the causes of brain size evolution, no systematic reviews have been conducted to explain brain size in anurans. Here, we review whether brain size evolution supports the cognitive buffer hypothesis (CBH), the expensive tissue hypothesis (ETH), or the developmental cost hypothesis (DCH) by analyzing the intraspecific and/or interspecific patterns in brain size and brain regions (i.e., olfactory nerves, olfactory bulbs, telencephalon, optic tectum, and cerebellum) associated with ecological factors (habitat, diet and predator risk), sexual selection intensity, life-history traits (age at sexual maturity, mean age, longevity, clutch size and egg size, testis size and sperm length), and other energetic organs. Our findings suggest that brain size evolution in anurans supports the CBH, ETH or DCH. We also suggest future directions for studying the relationships between brain size evolution and crypsis (i.e., ordinary mucous glands in the skin), and food alteration in different developmental stages.
Jae-Kang Lee, Hyun-Su Hwang, Tae-Kyung Eum, Ho-Kyoung Bae and Shin-Jae Rhim
In this study, we set out to determine the cascade effects of slope gradient on ground vegetation and small-rodent populations in a forest ecosystem. We focused on two forest-dwelling small rodents with different habitat requirements, the striped field mouse Apodemus agrarius (preferring dense ground vegetation) and the Korean field mouse A. peninsulae (dense forest and woodland). The study area comprised natural deciduous forests and Japanese larch Larix kaempferi plantations in South Korea. The abundance of A. agrarius but not that of A. peninsulae was related to slope gradient. There was a negative effect of slope gradient on ground vegetation coverage and a positive effect of ground vegetation on A. agrarius populations. Our results highlight that the population of A. agrarius was indirectly influenced by the negative effects of slope gradient on ground vegetation. Slope gradient can, therefore, be a limiting factor in the microhabitats occupied by small rodents. This study reveals a critical role for slope gradient since it can modify not only microhabitat conditions, but also small-rodent populations, and this finding can contribute to improved microhabitat management.
Mathilde Le Covec, Carla Aimé and Dalila Bovet
An interest in producing sounds during play behaviour might be a forerunner for music. Thus, we explored object play behaviour involving sounds in cockatiels (Nymphicus hollandicus). We provided them with several objects producing sounds and recorded sound production, spontaneous warbles and drumming during breeding, pre- and post-breeding. Birds manipulated the objects in a playful way. They manipulated them less during breeding than during pre- and post-breeding, but the proportion of manipulations producing sounds were higher during post-breeding and breeding than during pre-breeding. Males manipulated the objects more frequently and produced more sounds than females. Youngsters manipulated the objects more than adults. One bird repeatedly put a bell on a xylophone; we discuss several possible explanations for the behaviour, including tool use. Only males warbled and drummed, and during breeding only. Our results suggest an enriching effect of the objects on the birds. Many aspects of musicality remain to be studied.
T.N. Wittman and B.H. King
In haplodiploid species, daughter production, but not son production, is sexual, requiring paternal contributions. Females may use male signals to choose a mate with better daughter-production potential, if the choice facilitates her production of adaptive sex ratios, e.g., female-biased sex ratios in systems operating under local mate competition (LMC). In the parasitoid wasp Urolepis rufipes, females preferred pheromone markings from males that had mated once versus multiply, were young rather than old, and were uninfected rather than infected when infection was low, but not when infection was high. Mates of singly-mated males had more female-biased offspring sex ratios than those of multiply-mated males, whereas there was no difference for mates of young versus old males. Thus, female preference for singly-mated males appears to provide indirect fitness benefits. A preference for young males, was not beneficial in the laboratory, but in nature young males may have mated less.
Ricardo de Sá Rocha Mello, Scott Jarvie, Lindsay Hazley and Alison Cree
Individually identifying animals is key to ecological research. Natural marks and patterns of animals that remain stable through time may be used to identify individuals, either manually or with the aid of software. Here we compare the performance of three body parts (chest, right side and right eye) for individual identification of tuatara (Sphenodon punctatus) using three software packages (Wild-ID, I3S and StripeSpotter). We also explored pattern stability over time for the chest and right side, and whether the identification rate differed between life-history stages (adults and juveniles) for this long-lived reptile. We used photos of 196 tuatara, including captive and free-roaming individuals. In an initial analysis with a subset of individuals, chest and right side gave better identification rates than the eye when analysed using Wild-ID (the best-performing software). In a further analysis using all photos and Wild-ID, the false rejection rate was lower for chest (0.6%) than right side (2.4%). Although the effect of time on matching scores for chest (up to 3.5 y) and right-side (up to 1.8 y) was significant, it was not large enough to reduce the matching rate; furthermore, no difference in identification rate between adults and juveniles was detected. Overall, chest was the best-performing body part and Wild-ID the best-performing software. Thus, appropriate choice of body pattern for analysis may significantly increase the matching rate, and, as previously shown, software packages vary in performance.
Claire M. Curry and Michael A. Patten
Understanding factors that contribute to song divergence bolsters our understanding of signal evolution and reproductive isolation. Hybrid zones often occur across environmental gradients; as such, they are excellent places to examine how signals diverge and how differentiation is maintained. We studied song variation across two hybrid zones, one old and one recent, of Tufted Titmouse (Baeolophus bicolor) and Black-crested Titmouse (B. atricristatus), across an environmental gradient where the two titmouse populations meet. In the recent zone, noise and vegetation structure were correlated with several song characteristics, but in the older zone, these features did not correlate despite similar gradients in song features. Our data, combined with previous studies, suggest that despite overall similarities in characteristics, songs in the older zone may be more shaped by sexual selection, whereas songs in the young zone are shaped by environment. Thus, even within the same species, processes shaping signal structure can vary spatially and temporally.
Andre C. Bruinjé, Mauricio O. Moura, Bruno S. Maggi, Vinicius A. São-Pedro, Daniel M.A. Pessoa and Gabriel C. Costa
Animal colouration plays a key role in inter and intraspecific interactions, pre-eminently in mate signalling. When multiple types of colouration occur within sexes it is possible that they show alternative reproductive strategies. In lizards, most colouration studies do not incorporate how colour is perceived by conspecifics. Here, we used unbiased colour analysis methods (spectrophotometry and visual modelling) to test for sexual dimorphism and within male dichromatism in the Striped Lava Lizard. We found that males express two distinct colourations that are different from females in several dorsal and ventral body regions. Our results showed UV reflection at the throat, an important body region for signalling. Ventral patches, the coloured badge seen in adult males of Tropidurus spp., have two distinct colour classes within males (Y and B males). Morphs are best discriminated by blue and yellow chroma, and brightness. Body size had little influence on colouration, suggesting that colour may be linked to inheritance rather than growth. Our study clearly shows sexual dichromatism and the existence of colour morphs in this species. Moreover, morph differences in colouration are perceptible by conspecifics. These differences are not only between ventral patches, but also in other body parts such as the dorsum, previously considered as cryptic by human observers. We suggest that colouration at the ventral patches and throat might play a role in intraspecific interactions. Patches increase colour intensity during breeding season and are likely to be costly by pigment-based expression, whereas throat’s UV reflection might have a cost infringed by conspicuousness.
Geoffrey R. Smith, Jessica E. Rettig, Mallory Smyk, Maggie Jones, Genevieve Eng-Surowiec, Davit Mirshavili and Jeremy Hollis
Predation by native and non-native predators on the eggs, embryos, and early stage tadpoles can affect the recruitment of offspring into a population. We examined the effects of native (Little Brown Mudbugs, Cambarus thomai; overwintered Rana tadpoles; Common Green Darner, Anax junius, larvae) and non-native (Western Mosquitofish, Gambusia affinis) potential predators on the eggs, hatchlings, and early tadpoles of the Green Frog (Lithobates clamitans). The predators had no effect on survivorship or hatching of L. clamitans eggs. However, tadpole survivorship was significantly reduced by dragonfly larvae and crayfish, but not G. affinis or the overwintered ranid tadpoles. Our observation that invertebrates consumed Green Frog tadpoles while vertebrates did not is consistent with palatability contributing to the tadpoles’ susceptibility to different predators. Our results therefore suggest Green Frog tadpoles, but not eggs or embryos, from some populations may be subject to differential predation by invertebrate and vertebrate predators.
Maria Cristina Lorenzi, Alice Araguas, Céline Bocquet, Laura Picchi and Claire Ricci-Bonot
In outcrossing hermaphrodites with unilateral mating, where for each mating interaction one individual assumes the female role and the other the male role, each individual must take a sexual role opposite to that of its partner. In the polychaete worm Ophryotrocha diadema, the decision on sexual role is likely at stake during the day-long courtship. Here we describe, for the first time, courtship and pseudocopulation in this species, quantify their pre-copulatory behavior, and search for behavioral traits predicting the prospective sexual role (i.e., behavioral sexual dimorphism), by analyzing the courtship behavior of pairs of worms during the day preceding a mating event. We did not find any behavioral cue predicting the sexual role worms were to play; partners’ pre-copulatory behaviors were qualitatively and quantitatively symmetrical. We interpret this as the outcome of a war of attrition where partners share the preference for the same sexual role, and both hide their ‘willingness’ to play the less preferred one, until one individual reaches its cost threshold and accepts the less preferred sexual role.
Paola A. Olivero, David E. Vrech, Mariela A. Oviedo-Diego, Camilo I. Mattoni and Alfredo V. Peretti
In most animal species, body condition has a fundamental role in fitness. In males, sexual selection generally favors larger body size or greater weight. This may result in males with better condition performing more vigorous courtships, and biasing female preferences. The effects of body condition on mating performance have been extensively studied in different animal groups. Among arachnids, scorpions are an interesting group for evaluating the effects of these sexual traits on mating performance, since they exhibit an ancient mode of indirect sperm transfer. Scorpion males deposit a single spermatophore on the soil to transfer the sperm to the females, and therefore, the production of spermatophores involves a high cost for them. In this study, we use the scorpion Bothriurus bonariensis as a model to evaluate different patterns of sexual behavior as a function of the body condition of both males and females. We found that males with a better body condition performed the mating dance stage more quickly than males with a lower condition. In addition, males performed the sexual sting behavior for a longer time with females in a better condition. Our results suggest that a better condition provides a mating advantage to males and represents an indicator of courtship performance. Given that female quality is usually correlated with fecundity, males mating with females with a better body condition probably have higher reproductive success.
Jason Airst and Susan Lingle
Courtship behaviour reflects characteristics of an animal’s general biology, while also reflecting selective pressures specific to reproduction. Mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus) are sister species that differ in antipredator behaviour and sociality. We observed sympatric mule deer and white-tailed males to document their grouping patterns, courtship tactics, and aggressive interactions during the breeding season. Consistent with the hypothesis that courtship strategies reflect species differences in antipredator tactics and sociality, mule deer males were more likely than white-tailed males to tend females in multi male–multi female groups. White-tailed males almost exclusively tended females in isolated pairs and prevented other males from joining their groups. However, both species spent more time in isolated pairs as courtship advanced, likely to reduce competition. Our results enabled us to distinguish courtship behaviours that reflect contrasting antipredator tactics and sociality from courtship behaviours that reflect reproductive selective pressures that the species share.
Daniel Jablonski, Zoltán T. Nagy, Aziz Avcı, Kurtuluş Olgun, Oleg V. Kukushkin, Barbod Safaei-Mahroo and David Jandzik
The smooth snake, Coronella austriaca, is a common snake species widespread in the Western Palearctic region. It does not form conspicuous morphological variants and, although several evolutionary lineages have been distinguished based on the analyses of the mitochondrial DNA sequences, only two subspecies with very limited distribution have been traditionally recognized. Here we present an mtDNA phylogeography of the species using geographically extended sampling while incorporating biogeographically important areas that have not been analyzed before, such as Anatolia, Crimea, and Iran. We find that the smooth snake comprises 14 distinct phylogenetic clades with unclear mutual relationships, characterized by complex genetic structure and relatively deep divergences; some of them presumably of Miocene origin. In general, the biogeographic pattern is similar to other Western Palearctic reptiles and illustrates the importance of the main European peninsulas as well as the Anatolian mountains, Caucasus, and Alborz Mts. in Iran for the evolution of the present-day diversity. Considerable genetic structure present in the smooth snake populations within these large areas indicates the existence of several regional Plio-Pleistocene refugia that served as reservoirs for dispersal and population expansions after the glacial periods. The current taxonomy of C. austriaca does not reflect the rich genetic diversity, deep divergences, and overall evolutionary history revealed in our study and requires a thorough revision. This will only be possible with an even higher-resolution sampling and integrative approach, combining analyses of multiple genetic loci with morphology, and possibly other aspects of the smooth snake biology.
Esther van der Meer, Nick Lyon, Thomas Mutonhori, Roseline Mandisodza-Chikerema and Peter Blinston
When selecting prey, carnivores optimise energy gained when consuming prey against energy spent when pursuing and subduing prey. Additionally, predators seem to preferentially predate on prey which presents a low risk of injury. When defending itself against predators, baboons (Papio spp.) can inflict serious injury and cause mortality. Although part of Africa’s large carnivores’ diet, predation on baboons is usually avoided. We investigated prey selection patterns of African wild dogs (Lycaon pictus) in Mana Pools National Park, Zimbabwe. Based on direct and indirect observations and analyses of faecal samples, we show that baboons form a substantial part of the African wild dog diet and were more frequently predated on than would be expected based on availability. Predation on baboons did not vary over baboon sex or age classes but was affected by seasonality. This is the first study to describe a preference for predation on this unusual prey species.
Jay W. Schwartz and Harold Gouzoules
Screams are phylogenetically widespread and typically associated with emotionally intense contexts, and thus present a window into the evolution of vocal emotion expression. Screams are distinct from other vocalizations, but nonetheless exhibit acoustic variation. The purpose of this study was to assess whether humans are sensitive to this variation, specifically, whether they base perceptions of screamer arousal on the pitch and/or duration of screams. A forced choice task revealed a significant tendency to perceive longer or higher-pitched (but otherwise acoustically identical) screams as more emotionally intense than shorter or lower-pitched screams, respectively. This pattern was independent of participants’ gender, empathy score, and previous exposure to screams in the media. Furthermore, scream pairs exhibiting greater differences in duration yielded more consistent responses. Evolutionary implications relating to the acoustic correlates of arousal across mammalian species, as well as the socioecological functions of screams in other primates, are discussed.
Heitor Bruno de Araujo Souza, Washington Luiz Silva Vieira, Gabriel Corrêa Costa and Alexandre Vasconcellos
The present study sought to determine whether the defense mechanisms of termites influence the rate of consumption by lizards, and if that pattern differs between lizard species. Termites with different defense mechanisms (mechanical and chemical) were offered to two species of lizards from different lineages (Tropiduridae and Teiidae). We found that termites that used defensive chemicals were less likely to be eaten by lizards of both lineages. Our results indicate that lizards from both lineages are capable of selecting termites based on their defense mechanisms. As a result, there is no apparent direct link between the rate of termite consumption and their abundance in the ecosystem. Therefore, the use of stomach contents as a proxy to measure prey availability may render a bias estimation of termite abundance in the environment.
Abid Hussain, Tariq Mahmood, Faraz Akrim, Shaista Andleeb, Hira Fatima, Abdul Hamid and Muhammad Waseem
The wide distribution of a predator can reflect its flexibility in adapting to various ecosystems. The common leopard (Panthera pardus) is “Critically Endangered” in Pakistan while the IUCN Red List categorizes it globally as “Vulnerable”. This study investigated the distribution of the common leopard and the contribution of livestock in its diet in District Sudhanoti of Azad Jammu and Kashmir. During the surveys, scats, pugmarks, prey remains, and dead bodies of the common leopard were recovered in a scanned area of approximately 262 km2. The scats were mostly found on tracks and trails in hilly terrain, and pugmarks in the riparian zone and nallas, while prey remains were found mostly in dense bushes and rocks. Dead common leopards were recovered within or around village areas. All signs of the species were found between 418 m and 2016 m elevation above sea level. Scat analysis revealed a total of ten prey species including seven domestic mammals and only three wild meso-mammals. Domestic animals were most frequently consumed while wild prey contributed significantly less. The consumption of domestic prey species was found not to differ between the summer and winter season. We conclude that the common leopard was sustaining mainly on livestock with a much smaller contribution from wild prey. This fact, along with the “Critically Endangered” status of the species in the country, demands effective conservation measures to be taken to save common leopards.
Victoria I. Austin, Justin A. Welbergen, Alex C. Maisey, Meghan G. Lindsay and Anastasia H. Dalziell
Reproductive suppression, whereby individuals decrease the reproductive output of conspecific rivals, is well-studied in mammals, but while it is suspected to be widespread in birds, evidence of this phenomenon remains rare in this class. Here we provide compelling evidence of reproductive suppression in the Superb Lyrebird (Menura novaehollandie), with the first audio-visual documentation of the destruction of one female’s nest by another. We propose that nest destruction may be a strategy that females use in protracted territorial negotiations spanning multiple breeding seasons, and discuss how reproductive suppression could explain puzzling nesting behaviours in this species, such as the construction of multiple unfinished nests in each breeding season. More broadly, these results reveal high intra-sexual competition among female lyrebirds, and thus may provide an explanation for their elaborate vocal displays.
Joana Sabino-Pinto, E. Tobias Krause, Molly C. Bletz, An Martel, Frank Pasmans, Sebastian Steinfartz and Miguel Vences
Epidemiology relies on understanding the distribution of pathogens which often can be detected through DNA-based techniques, such as quantitative Polymerase Chain Reaction (qPCR). Typically, the DNA of each individual sample is separately extracted and undergoes qPCR analysis. However, when performing field surveys and long-term monitoring, a large fraction of the samples is generally expected to be negative, especially in geographical areas still considered free of the pathogen. If pathogen detection within a population – rather than determining its individual prevalence – is the focus, work load and monetary costs can be reduced by pooling samples for DNA extraction. We test and refine a user-friendly technique where skin swabs can be pooled during DNA extraction to detect the amphibian chytrid fungi, Batrachochytrium dendrobatidis and B. salamandrivorans (Bsal). We extracted pools with different numbers of samples (from one to four swabs), without increasing reaction volumes, and each pool had one sample inoculated with a predetermined zoospore amount. Pool size did not reduce the ability to detect the two fungi, except if inoculated with extremely low zoospore amounts (one zoospore). We confirm that pooled DNA extraction of cutaneous swabs can substantially reduce processing time and costs without minimizing detection sensitivity. This is of relevance especially for the new emerging pathogen Bsal, for which pooled DNA extraction had so far not been tested and massive monitoring efforts in putatively unaffected regions are underway.
Kathleen Preißler, Alexander Dennis Watzal, Miguel Vences and Sebastian Steinfartz
In the face of the global biodiversity crisis, the monitoring of species richness and diversity is experiencing an increased demand entailing a raise in cost and time investment. The analysis of species-specific DNA fragments in environmental samples (eDNA) such as from water or soil, facilitate the molecular detection of species without the specific sampling of individuals. The invasive chytrid fungus Batrachochytrium salamandrivorans (Bsal) is infecting natural fire salamander populations (Salamandra salamandra) and causes chytridiomycosis resulting in infrequent regional extinctions of populations across Central Europe. With regard to the expanding distribution of Bsal over the last years, cost-effective monitoring of fire salamanders is important for the conservation of this species. Based on a real-time quantitative PCR (qPCR) assay, we developed a new protocol to detect S. salamandra larvae in streams via eDNA, using species-specific primers of the mitochondrial control region (D-loop). We tested the efficiency of qPCR primer sets for six combinations of DNA extraction kits coupled with subsequent PCR inhibitor removal kits for obtaining qPCR-detectable S. salamandra eDNA from water filters, that were taken both from natural streams and artificial water tanks in the laboratory as positive controls. We found that the DNeasy Blood & Tissue Kit in combination with the DNeasy PowerClean CleanUp Kit performed best for detecting salamander larvae from natural streams. Our experimental protocol paves the way for resource-saving approaches to monitor S. salamandra larvae, but also confirms the limits to this eDNA approach in that it requires optimized laboratory protocols.
P. Sánchez-Hernández and M. Molina-Borja
Morphological and behavioural traits influence contest development and outcome. We analysed morphological and behavioural traits in male and female staged contests of Chalcides viridanus along breeding time. There was no significant difference in any morphologic trait for winner and looser male contenders; larger hind-limbs and heads were significantly associated to winner females. ‘Approach’ was positively while ‘flee’ negatively associated to winner males. ‘Tongue-flick’ and ’approach’ were positively associated to female winners and ‘flee’ to losers. Contest intensity was higher in male than in female contests. For males it was higher in May than in March or April but for females in April and May than in March. Contest intensity was positively related to head width in loser males, suggesting fitting to a pure self-assessment model. For females there was no significant association. For the first time we have shown that skink female contests are as complex as those of males.
Yun-Tao Yao, Yu Du, Meng-Chao Fang, Long-Hui Lin and Xiang Ji
We have studied resting metabolic rate (RMR) of the water monitor lizard (Varanus salvator) at different developmental stages (hatchling, juvenile and adult) to test whether individuals at different ages differ in RMR when controlling for the effects of body mass. We found that: 1) resting metabolic rates of hatchlings, juveniles and adults were all positively related to their body mass with the same coefficients and that 2) developmental stage had a non-significant influence on the resting metabolic rate when controlling for the effects of body mass. Our results suggest that variation in resting metabolic rate for V. salvator is directly caused by body mass differences, which conforms to previous findings in mammal species and birds.
Junior Nadaline, André E. Confetti and Marcio R. Pie
In a series of papers starting in the early 1980s, Toft proposed a general scenario to explain dietary evolution in leaf litter anurans in which species would “form a continuum from those that specialize on ants and mites, through generalists, to species that avoid ants and mites”, and these differences would in turn correlate with foraging strategies, morphology, and defense mechanisms. In this study, we reassess this hypothesis using a global dataset on the dietary composition of 120 anuran species. Surprisingly, we found that the relative contribution of ants and mites in anuran diets were largely orthogonal to one another. Moreover, we did not find evidence for the continuum of dietary composition envisioned by Toft. These results suggest that, although ants and mites have played a major role in the evolution of aposematic species, the trends found in those species might not be directly extrapolated to all leaf litter anurans.
Duong Thi Thuy Le, Jodi J.L. Rowley, Dao Thi Anh Tran and Huy Duc Hoang
While deforestation is one of the greatest drivers of biodiversity loss, our understanding of the effects of habitat modification on species is limited. We investigated the diet of a forest-dwelling frog species, Morafka’s frog (Odorrana morafkai), in a highland forest in Vietnam in relation to habitat disturbance, sex and season. We surveyed the species at 45 sites in forest of varying disturbance and examined its diet using stomach flushing, estimating prey availability via trapping. We detected significantly fewer O. morafkai in highly disturbed habitats compared to moderately disturbed or non-disturbed habitats. We revealed that O. morafkai is a dietary generalist, identifying 28 prey types, primarily invertebrates. Prey composition, the number of prey items per stomach and prey volume per stomach did not vary between disturbance levels. Diet did not vary significantly between sexes, except that females had a higher prey volume. Prey composition in the species varied between seasons, with Coleoptera and Orthoptera dominating the diet in the rainy season and Lepidoptera in the dry season. The number of prey items per stomach and prey volume were significantly higher in the rainy season. There was a significant correlation between prey availability and diet composition. The low number of O. morafkai detected in highly disturbed habitats suggests that this habitat may not be optimal for the species, despite having a generalist feeding strategy and presumed high mobility. This study provides a window into the impact of an increasing threat, habitat disturbance, on forest-dependent amphibian species.
Sara Davey, Melanie Massaro and Rafael Freire
Although flight initiation distance (FID) has been shown to be shorter in urban compared to rural populations of birds, less is known about how the characteristics of the urban environment, such as the population size and age of the city influences the FID and other aspects of anti-predator behaviour. Urban willie wagtails and magpie larks in a relatively small and new town had shorter FID than rural conspecifics. Both species were more likely to show a short, rather than long, escape flight if the experimenter started walking towards the bird from further away. There was some indication that urban birds may be more likely to show a short escape flight than rural birds. We conclude that anti-predator responses of birds can be influenced by a relatively small, recently established and sparsely-populated town. Additionally, the possibility of the characteristics of the urban centre influencing variation in the FID response is discussed.
Arianna De Marco, Nancy Rebout, Elodie Massiot, Andrea Sanna, Elisabeth H.M. Sterck, Jan A.M. Langermans, Roberto Cozzolino, Bernard Thierry and Alban Lemasson
The investigation of vocal similarity between individuals has provided evidence of the flexibility of communication signals. This study evaluates the impact of group membership, affiliative bonds, kinship and dominance on acoustic similarity in two primate species with different social styles, intolerant rhesus macaques and tolerant Tonkean macaques. We focused on the fundamental frequencies of the contact calls emitted by adult females. Close kinship promoted vocal similarity between individuals in both species, and also group membership in Tonkean macaques, indicating the involvement of experiential and/or genetic factors. In rhesus macaques more similarities were observed between partners with strong or weak dominance asymmetry than between those with medium asymmetry, which again points to the role of experience. No evidence was found that dominance influences vocal similarity in Tonkean macaques. Our results provide additional evidence to the flexibility of vocal signals produced by macaques, and reveal that it is influenced by social style.
Ivan Prates, Paulo Roberto Melo-Sampaio, Kevin de Queiroz, Ana Carolina Carnaval, Miguel Trefaut Rodrigues and Leandro de Oliveira Drummond
Recent biological discoveries have changed our understanding of the distribution and evolution of neotropical biotas. In the Brazilian Atlantic Forest, the discovery of closely related species isolated on distant mountains has led to the hypothesis that the ancestors of montane species occupied and dispersed through lowland regions during colder periods. This process may explain the distribution of an undescribed Anolis lizard species that we recently discovered at a montane site in the Serra dos Órgãos National Park, a popular tourist destination close to the city of Rio de Janeiro. To investigate whether this species is closely related to other Atlantic Forest montane anoles, we implement phylogenetic analyses and divergence time estimation based on molecular data. We infer the new species nested within the Dactyloa clade of Anolis, forming a clade with A. nasofrontalis and A. pseudotigrinus, two species restricted to montane sites about 400 km northeast of Serra dos Órgãos. The new species diverged from its sister A. nasofrontalis around 5.24 mya, suggesting a cold-adapted lowland ancestor during the early Pliocene. Based on the phylogenetic results, we emend the definitions of the series taxa within Dactyloa, recognizing a clade containing the new species and several of its relatives as the nasofrontalis series. Lastly, we provide morphological data supporting the recognition of the new species and give it a formal scientific name. Future studies are necessary to assess how park visitors, pollutants, and shrinking montane habitats due to climate change will affect this previously overlooked anole species.
Carlos de la Cruz, Mónica Expósito-Granados and Juliana Valencia
In many species of cooperative breeding birds, breeders and helpers participate in the parental care with different food provision rules. Normally, helpers feed nestlings less frequently and with smaller quantities of food than breeders. But studies analysing the reaction of feeders to nestling demand are scarce and rarely measure the quantity of food that is actually delivered. In this study, we analysed the provisioning effort of breeders and helpers in the Iberian Magpie, Cyanopica cooki, and how this effort varies with brood demand. We did so by measuring the nestling feeding rate and the biomass supply of each individual. In this way, we obtained a more accurate measurement of the investment assumed by each individual belonging to each status. We found that breeding males visited the nest more often than both breeding females and helpers (mean = 2.24; 0.85 and 1.58, respectively). Furthermore, breeding males delivered more biomass in each feeding visit to the nest than those from other statuses. Breeders, both male and female, increased their parental effort (i.e., provisioning rate and biomass) when brood demand was higher (i.e., more siblings and older nestlings), whereas helpers contributed differently to the nest, but depending on the two types of helpers occurring in this species. Differences in the possible benefits obtained by breeders and helpers may explain these different strategies. In addition, male and female breeders (but not helpers) reduce the feeding rate throughout the breeding season. Thus, in the Iberian magpie, breeders and helpers reveal different patterns of investment depending on nestling food demand.
Thomas Hesselberg, Daniel Simonsen and Carlos Juan
Interest for subterranean biology has risen sharply in recent years due to the simplicity of the cave environment. However, most studies have focussed on morphology with few studies looking at behaviour. The cave orb spiders show some unique behavioural adaptations compared to other orb spiders, including rudimentary orb webs, off-web foraging and a complex life cycle with a surface phase. Here, we compare these behavioural adaptations in the European Meta menardi and Meta bourneti to similar behaviours in surface-dwelling orb spiders. We find that current data suggest (1) an extreme reduction in the number of frame threads, (2) evidence of capturing non-flying prey, but not necessarily evidence for off-web foraging and (3) dispersal through a surface-dwelling life stage, but with data lacking on the role of ballooning and their return to caves. We conclude that Meta spiders have potential as model organisms for studies on behavioural adaptations and flexibility.
H. Takada and M. Minami
One aim of animal behaviour research is to explain why animals live in groups. The grouping behaviour of solitary mammals is important for understanding the ecological factors promoting the evolution of sociality. We present field data of Japanese serow, a primitive solitary ungulate, in forest and alpine meadow habitats. We found no differences in group size of all age–sex classes between the forest and alpine meadow habitats, and both populations were mainly solitary. The current findings suggest that group size in the serow is not affected by ecological conditions, including habitat structure, forage abundance, and population density. However, female associations involving up to three females occurred in the alpine meadow habitat throughout the year, whereas such groupings were not observed in the forest habitat. This finding suggests that abundant food supply in the alpine meadow promoted female associations by decreasing the cost of food resource competition.
Astrid T. Groot and Z. Valentina Zizzari
Global climate is changing at a rapid pace and the pivotal question is if the rate and extent of species’ responses to stressful events enable them to persist in a changing world. Although the consequences of rapid environmental changes on animal life-history traits are receiving considerable attention, our understanding of how temperature fluctuations affect sexual chemical communication in animals is scarce. Male-female interactions often depend on pheromone detectability and sudden shifts in environmental temperature are expected to disrupt communication between potential mates. Whether organisms can adapt to temperature-induced changes at both signaller and receiver levels is virtually unexplored. In this perspective paper, we first provide a broad overview of the sex pheromone pathway, from biosynthesis to detection, and outline the importance of chemical-based mate choice. Finally, through several study cases, we highlight how thermal stress may interfere with chemical communication between the sexes, and discuss the potential evolutionary consequence of temperature stress.
Keiko Oku, Tom A.R. Price and Nina Wedell
Immunity is an important mechanism of protection against pathogens and parasites. One factor that can influence immunity is mating. During mating, male-derived materials are transferred to females, and the physical contact also involves the potential risk of sexually transmitted infections, and wounding. Thus, mating can challenge a female’s immune system. This review focuses on exploring how immunity and mating interact in female insects. Although mating has been shown to cause female immune responses in several species, the responses do not always match the observed resistance to pathogens/parasites. Mating up-regulates female immune responses while female resistance is reduced compared to virgin females in some species, and vice versa in other taxa. We discuss why mismatches occur and why post-mating female resistance differs among species, and suggest that measured immune responses may not correlate with female resistance. Also, the mating system will play a major role. Polyandrous mating systems can generate intense post-mating sexual conflict, which can impose high costs of mating on females. Reduced female post-mating resistance may be due to direct suppression of female immunity by males. Alternatively, polyandry may increase the risk of sexually transmitted infections. If this is the major factor driving female post-mating resistance, females of polyandrous species should have higher post-mating immunity. To date, there are insufficient numbers of studies to fully answer the question ‘does mating negatively affect female immune defences in insects?’ To elucidate the links between immunity and mating in females, we need more studies in more species with varied mating systems.
Yun Lin Cai, Chun Lan Mai, Xin Yu and Wen Bo Liao
Sexual selection theory states that the premating (ornaments and armaments) sexual traits should trade off with the postmating (testes and ejaculates) sexual traits, assuming that growing and maintaining these traits is expensive and that total reproductive investments are limited. Male-male competition and sperm competition are predicted to affect how males allocate their finite resources to these traits. Here, we studied relative expenditure on pre- and postmating sexual traits among 82 species for three mammalian orders with varying population density using comparative phylogenetic analysis. The results showed that population density affected sexual size dimorphism (SSD) in both Artiodactyla and Carnivora, but not in Primates. However, relative testis mass and sperm size were not affected by population density. Moreover, we did not find associations between the SSD and testis mass or sperm size in three taxonomic groups. The interspecific relationships between pre- and postcopulatory sexual traits did not change with increased population density. Our findings suggest that population density did not affect variation in the relationship between pre- and postcopulatory sexual traits for these three mammalian orders.
Fahmida Wazed Tina
The alteration of signals of animals in response to changes in environmental factors is a common phenomenon. In male fiddler crabs, waving major claws towards females is energetically costly; thus, males need to adjust their waving in a way that increases the chance of potential mate attraction while reducing the waving cost. In this study, I examined how Austruca perplexa males adjusted their waving rate based on male-male competition (male numbers in a cluster [Austruca perplexa males make groups and wave synchronously towards females]), female body size, and the distances of the receiver females from the signaller males. Forty clusters were selected randomly; from each cluster, I randomly selected one male, video recorded his waving behaviour and calculated waving rate (waves/min). Body size (carapace width) and distances of receiver females were measured. To analyze the effects of competition, female size, and their distances on male waving rate through binary logistic regression analysis, all variables were divided into two categories (male waving rate: low and high, competition: low and high, female size: small and large, and female distances: short and long) based on a median split method. Afterwards a series of binary logistic regression models were built and the relative supports of various models were assessed based on the corrected Akaike information criterion. Results showed that competition, female body size and their distances affected the male waving rate in an additive manner, but their interactions did not show any effect. Further research can be conducted to investigate how breeding season and predation risk along with competition, female size and female distances affect the claw-waving display of male fiddler crabs.
Peng Hong-bi, Hou Dong-min, Zhang Di and Zhu Wan-long
The metabolic switch hypothesis refers to an ability to adjust metabolic rate. It plays a key role in animals adapted to periods of food shortage, enabling them to “switch down” their resting metabolic rate and to survive and maintain their weight indefinitely on limited rations. The present study investigates the energy strategies of a small mammal in response to food shortages as a function of food restriction, metabolic rate and ambient temperature. We subjected tree shrews (Tupaia belangeri) to food restriction and measured body mass, survival rate, resting metabolic rate, non-shivering thermogenesis and cytochrome c oxidase activity of brown adipose tissue. Cold-exposed animals restricted to 80% of ad libitum food intake had significantly increased resting metabolic rate and non-shivering thermogenesis and decreased body mass and survival rates compared with those kept as control group on the same ood restriction level. Animals classified as having a high resting metabolic rate consumed 30.69% more food than those classified as having a low resting metabolic rate, but showed no differences in body mass or survival when restricted to 80% of ad libitum food intake. These results indicate that tree shrews, known for their relatively high metabolic rates, are sensitive to periods of food restriction, which supports the metabolic switch hypothesis. Our findings are also consistent with the prediction that small mammals with food hoarding behaviors, like tree shrews, may have a lower tolerance for food shortages than non-hoarding species.
Rui Zhang, Dianlei Han, Qiaoli Ji, Guoyu Li, Xian Li and Jianqiao Li
When studying the gait of pheasants, an intermittent-flight bird, it is necessary to take into account changes in the gaits and hindlimb joint angles resulting from increases of speed. In this study, pheasant locomotion postures were recorded on a speed-variable treadmill with high-speed cameras. Firstly, kinematic analysis showed that the stride cycle of pheasants decreased and the stride length increased with increasing speed. The duty factor also decreased, but was less than 0.5 in only about 10% of measurements. Thus, pheasants are more inclined to choose the grounded running or walking gait in laboratory situations. Secondly, changes in the tarsometatarso-phalangeal joint angle and the intertarsal joint angle at touch-down, mid-stance and lift-off concomitant with speed variation were studied. Tarsometatarso-phalangeal joint angle was found not to be significantly affected by changes in speed, but changed over larger ranges than the intertarsal joint angle. Thirdly, the continuous changes in the joint angles were studied during a complete stride cycle. The curves shifted leftward with increasing speed. Finally, the changes at four main positions were analyzed with increasing speed.
Gentile Francesco Ficetola, Raoul Manenti and Pierre Taberlet
In the last decade, eDNA and metabarcoding have opened new avenues to biodiversity studies; amphibians and reptiles are animals for which these new approaches have allowed great leaps forward. Here we review different approaches through which eDNA can be used to study amphibians, reptiles and many more organisms. eDNA is often used to evaluate the presence of target species in freshwaters; it has been particularly useful to detect invasive alien amphibians and secretive or rare species, but the metabarcoding approach is increasingly used as a cost-effective approach to assess entire communities. There is growing evidence that eDNA can be also useful to study terrestrial organisms, to evaluate the relative abundance of species, and to detect reptiles. Metabarcoding has also revolutionized studies on the microbiome associated to skin and gut, clarifying the complex relationships between pathogens, microbial diversity and environmental variation. We also identify additional aspects that have received limited attention so far, but can greatly benefit from innovative applications of eDNA, such as the study of past biodiversity, diet analysis and the reconstruction of trophic interactions. Despite impressive potential, eDNA and metabarcoding also bear substantial technical and analytical complexity; we identify laboratory and analytical strategies that can improve the robustness of results. Collaboration among field biologists, ecologist, molecular biologists, and bioinformaticians is allowing fast technical and conceptual advances; multidisciplinary studies involving eDNA analyses will greatly improve our understanding of the complex relationships between organisms, and our effectiveness in assessing and preventing the impact of human activities.
Patricio De Los Rios, Stefan Woelfl and Cristian Soto
With their ultraoligotrophic status, the Chilean North Patagonian lakes have mixotrophic ciliates in their pelagic environments as producers, whereas the primary consumers are crustaceans that are low in abundance and species numbers. The aim of the present study was to determine the potential grazer role of mixotrophic ciliates on crustacean zooplankton collected in a lake without mixotrophic ciliates. Three experiments were conducted; one had a control with mixotrophic ciliates and an experimental treatment including the copepod Boeckella gracilipes obtained from Caburgua lake, whereas the second and third experiments had a control without zooplankton, and three treatments with the addition of Daphnia pulex and Mesocyclops araucanus, and a third treatment with equal amounts of both species. The results revealed grazing effects on the mixotrophic ciliates in the experimental treatments. This finding supports the evidence from the field and experiments suggesting that, in the transition from oligotrophy to mesotrophy with consequent changes in zooplankton, species number and abundance of mixotrophic ciliates decrease in their abundance.
M. O’Hara, B. Mioduszewska, T. Haryoko, D.M. Prawiradilaga, L. Huber and A. Auersperg
When tested under laboratory conditions, Goffin’s cockatoos (Cacatua goffiniana) demonstrate numerous sophisticated cognitive skills. Most importantly, this species has shown the ability to manufacture and use tools. However, little is known about the ecology of these cockatoos, endemic to the Tanimbar Islands in Indonesia. Here we provide first insights into the feeding- and socio-ecology of the wild Goffin’s cockatoos and propose potential links between their behaviour in natural settings and their advanced problem-solving capacities shown in captivity. Observational data suggests that Goffin’s cockatoos rely on a large variety of partially seasonal resources. Furthermore, several food types require different extraction techniques. These ecological and behavioural characteristics fall in line with current hypotheses regarding the evolution of complex cognition and innovativeness. We discuss how the efficiency of (extractive) foraging may preclude tool use in wild Goffin’s cockatoos, even though the corresponding cognitive and ecological prerequisites seem to be present.
Eugenia Méndez, Alejandra A. López Mañanes and Silvina A. Pinoni
When a species often experiences variation in its environmental conditions, metabolic flexibility is required. We studied the duration of the digestive cycle and the activity of key digestive enzymes (proteolytic, amylase, lipase) at short and long times after feeding in the hepatopancreas of the osmoregulator crab Neohelice granulata from the Mar Chiquita coastal lagoon (Buenos Aires Province, Argentina). We compared these responses upon hyper-regulation and under osmoconformation conditions (10 and 35 psu). The results show the ability of this crab to hyper-regulate in different feeding states. No significant differences were observed in the duration pattern of the digestive cycle between hyper-regulation and osmoconformity. However, distinct responses after feeding were observed in the activities of the digestive enzymes studied in relation to the osmoregulatory state. In individuals exposed to 35 psu, proteolytic activity was higher at 8 h and remained constant until 72 h after feeding. At 10 psu, this activity was higher at 48 h after feeding than before feeding. At 35 psu, the amylase activity after feeding was greater than the prefeeding activity. No differences were observed in the activity of lipase at 35 psu, but at 10 psu this activity was lower 1 h after feeding than before feeding. This work constitutes a contribution to our knowledge of the physiology of crustaceans and attempts to clarify the possible mechanisms of digestive settings associated with hyper-regulation.
Erin E. Grabarczyk and Sharon A. Gill
During the breeding season, avian pairs coordinate interactions with songs and calls. For cavity nesting birds, females inside nest boxes may rely on male vocalizations for information. Anthropogenic noise masks male songs, which could affect information gained by females. We explored song transmission from a female house wren (Troglodytes aedon) perspective, testing the hypothesis that noise masking alters songs that reach females inside nest boxes. We broadcast songs at three distances up to 25 m from nest boxes and re-recorded songs using two microphones, positioned inside and outside nest boxes. We measured signal-to-noise ratios and cross-correlation factors to estimate the effects of masking on transmission. In noise, songs received inside nest boxes had lower signal-to-noise ratios and cross-correlation factors than songs recorded outside of boxes, and these effects decreased with distance. For females, noise may reduce information conveyed through male songs and in response pairs may need to adjust their interactions.
M.A. Alim, M.M.K. Hossain, J. Nusrat, Rubaya, M. Salimullah, Z. Shu-Hong and Jahangir Alam
The leptin receptor (LEPR) is involved in central signaling for both energy homeostasis and reproduction. The present study investigates the association of the LEPR gene with the prolificacy of Black Bengal goat. Two single nucleotide polymorphisms (SNPs) in intron 3 and one SNP in exon 4 in the LEPR gene were identified by pooled DNA sequencing. The identified SNPs were genotyped by the direct sequencing method from 84 Black Bengal does. A synonymous mutation (Lysine > Lysine) was found as a polymorphism in exon 4. The effects of the different genotypes on litter size traits were estimated using linear models. Our results show that goats with heterozygous genotype AG at the loci g.104911A>G and g.105151A>G showed the highest prolificacy performance when compared with the other, homozygous genotypes. Dominance and additive effects were observed at the considered loci. No significant allele substitution effects were found for any locus. Our results indicate preliminarily that LEPR may have some association with prolificacy and could be a candidate gene to improve the prolificacy in goat.
Joke Maes, Arend Raoul Van Oosten, Natalie Van Houtte and Erik Matthysen
Unique evolutionary potential could be lost when a population goes extinct or when individuals are translocated to other existing populations. Therefore, in order to identify priorities and to predict the efficiency and consequences of conservation actions, information is needed on the genetic structure of natural populations. In the urbanized and diverse landscapes of Flanders, Belgium, natterjack toad (Epidalea calamita) populations have been declining over the last decades. Therefore, this species is subjected to a wide range of different types of conservation measures (e.g. habitat management, corridor development, translocations). However, more information is needed on its genetic population structure. In this study, we sampled egg clutches from six populations and studied their genetic structure with six microsatellite markers. In total, 184 samples from 99 different egg strings were genotyped. Observed heterozygosity was generally high, even for the small and isolated populations (overall mean H O = 0.43). The weak clustering by the Bayesian analyses (STRUCTURE, Adegenet and BAPS) does not allow us to make strong conclusions on the population structure. However, the significant ΦST values between the populations underline the importance of genetic information when conservation priorities are discussed. Unique evolutionary potential could be lost when one or more natterjack toad populations would go extinct, and translocation of individuals to other existing populations should be considered with caution.
Valentina Rovelli, Aritz Ruiz-González, Leonardo Vignoli, Daniele Macale, Vincenzo Buono, Francesca Davoli, David R. Vieites, Nadav Pezaro and Ettore Randi
Next Generation Sequencing (NGS) and related technologies have revolutionized the field of conservation and population genetics, providing novel tools and the capacity to discover thousands of new Single Nucleotide Polymorphisms (SNPs) for the analysis of population parameters. However, gathering NGS data for organisms with very large genomes, such as amphibians, remains challenging because it is still unclear how the current methods perform. Here, we use the Genotyping-by-Sequencing (GBS) approach to generate SNP data for the genotyping of two amphibian species that are of conservation concern, the Sardinian brook salamander (Euproctus platycephalus) and the Italian stream frog (Rana italica). Both E. platycephalus and R. italica have very large genomes (5.53 Gb and >20 Gb, respectively) so genomic data are not available for either of them. We used 95 individual samples and one Illumina lane for each species, with an additional lane for E. platycephalus. After filtering, we obtained 961 and 854 high-coverage SNPs for E. platycephalus and R. italica, respectively. Our results suggest that GBS can serve as a reliable and cost-effective method for genotyping large amphibian genomes, including non-model species.
Can Wang, Long Jin, Zhi Ping Mi and Wen Bo Liao
Variation in organ structure likely provides important clues on local adaptation and reflects the pressure target of natural selection. As one of the important organs, the skin plays a key role in adapting to complex environments by reducing water loss or increasing water absorption. Nevertheless, variation in the skin structure across different populations in a single species of anurans remains enigmatic. Here, we studied geographical variation in the skin structure of male Andrew’s toads (Bufo andrewsi) across ten populations using histological methods. We quantified thickness of the skin, the epidermis, the loose layer, the compact layer, and of the epidermis, area of granular glands (GGs) and of ordinary mucous glands (OMGs), width of the calcified layer, and number of capillary vessels. We found that the thickness of the skin, dermis and loose layer in dorsal skin increased with latitude whereas the area of granular glands decreased with altitude. Moreover, the width of the calcified layer in ventral skin decreased with latitude among populations. Our findings suggest that geographical variation in skin structure in male B. andrewsi is likely to reduce water loss or make water absorption occur faster in complex high-latitude environments, improving local adaptation.
Marija Ilić, Vida Jojić, Gorana Stamenković, Vanja Marković, Vladica Simić, Momir Paunović and Jelka Crnobrnja-Isailović
We conducted a comparative (2D landmark-based geometric and traditional) morphometric analysis on tadpoles at early developmental stages. Two species of brown frog (Rana dalmatina and R. temporaria) and the common toad (Bufo bufo) were involved, all raised in the laboratory from fertilized eggs collected in their natural habitat. Taxonomic identification was confirmed by the DNA barcoding method with the 16S rRNA sequence as the gene marker. Interested to compare the methodologies for quantification and description of morphological differences among tadpoles of mentioned species, we aimed to: 1) calculate interspecies genetic distances as the most relevant measurement for species differentiation, 2) determine and describe size and shape variation, 3) identify relationships among the analyzed species at the morphological level and 4) assess their classification accuracy. Within the framework of the specified aims, both methodologies produced very similar results, i.e., the smallest divergence was between R. dalmatina and R. temporaria, while the most discriminative were B. bufo and R. temporaria. However, we observed subtle shape variation of the distal region of the tail that was detected only by the geometric morphometrics. Our findings support the following. Geometric morphometric method captures more subtle shape differences that were unable to be recovered from linear measurements. It performs slightly better in classification rate. Although it was not quantified, it stands to reason that there is no difference in time investment between the two approaches. Geometric morphometrics provides more information that can be leveraged to answer further questions and it has a clear advantage in visualizing.
María Celeste Luna, Carlos Roberto Vásquez-Almazán, Julian Faivovich and Andrés Eduardo Brunetti
Secondary sexual characters form a diverse group of traits widely spread in amphibians. Within anurans, the Hylini tribe represents an interesting group to examine the evolution of this type of characters because it has different skin structure modifications, including ventrolateral glands, nuptial pads, and unique swollen upper lips. We analysed the skin gland composition in the upper lip of Plectrohyla guatemalensis and the ventrolateral gland of Ptychohyla hypomykter (Hylidae: Hylinae: Hylini). Each of these species is characterized by a different type of sexually dimorphic skin gland; specialized mucous glands (SMGs) in Pl. guatemalensis and specialized serous glands (SSGs) in Pt. hypomykter. The SMGs conform to the general type of sexually dimorphic skin glands in amphibians, whereas SSGs are very rare. Because SMGs are likely involved in the production of sexual pheromones, their distinctive location and their co-occurrence with other secondary sexual characters like long and pointed maxillary and premaxillary teeth in Pl. guatemalensis suggests that the system used for their delivery may be a distinguishing behavioral feature in this species. The presence of both types of glands in Pt. hypomykter (SMGs in nuptial pads, and SSGs in ventrolateral glands) suggests a different or, at least, a complementary role of these two types of glands during reproduction.
Sylvain Dubey, Guillaume Lavanchy, Jacques Thiébaud and Christophe Dufresnes
Biogeographic processes have led to different evolutionary taxa occurring in the northern and southern edges of the Alpine Mountains in Western Europe. The integrity of this diversity is being challenged by frequent human-mediated trans-alpine translocations, sometimes leading to biological invasions. Several alien terrestrial vertebrates of south Alpine origins (Italy, Swiss Ticino) are causing damages to native north Alpine fauna. In this paper, we used molecular tools to characterize the understudied case of the Mediterranean smooth newt (Lissotriton vulgaris meridionalis) expanding in the outskirts of Geneva since its introduction before 1975. Mitochondrial and nuclear DNA sequencing suggest that these exotic populations are a mixture between two diverged L. v. meridionalis lineages from central Italy, and traces of potential hybridization with the native L. v. vulgaris was detected. This situation echoes many other trans-alpine alien introductions. We review all comparable cases of southern to northern Alps introductions in vertebrates, including seven reptiles and four amphibians. The majority of south alpine alien lineages were presumably imported voluntarily by enthusiasts and appear to perform better in the disturbed habitats found in the anthropogenic landscapes of Western Europe compared to their native north Alpine counterparts. Most pose serious threats to related species of similar ecology, through direct competition, predation and introgressive hybridization. Difficulties to detect alien species on time lead to significant conservation costs. Better education together with more appropriate and reactive management plans will be necessary to limit the impact of future alien introductions.
María de Fuentes-Fernández, Ma Mercedes Suárez-Rancel and Miguel Molina-Borja
Many selective pressures modulate microhabitat choice of ectotherms, such as temperature, humidity and habitat heterogeneity, and these vary in space and time. Here we analysed: 1) microhabitat selection comparing characteristics of stones (and their surroundings) under which geckos (Tarentola delalandii, mainly nocturnal) were found during the day with that of stones selected randomly; 2) relationship of a measure of body size to microhabitat characteristics (stone and herb covers, etc., and temperature/humidity) and cloacal temperature of males, females and juveniles from two contrasting habitats of Tenerife (northern and southern localities) and in two periods of the year (Spring-Summer and Autumn-Winter). In comparison with randomly selected stones, geckos significantly selected stones with lower temperature in the Spring-Summer and microhabitats with high stone cover. Gecko size was significantly larger in the Northern than in the Southern locality, in spring – summer than in autumn – winter and in males than in females. In both populations and time periods, the largest body sizes were significantly associated with higher environmental and shelter temperatures and with low values of humidity and stone cover. Cloacal and shelter temperatures were positively and significantly related; at higher values of the latter, juveniles attained significantly higher temperatures than adult males but lower than that of females. Larger body size was associated with high shrub and leaf litter covers and high values of shelter dimensions. Therefore, we suggest that in relation to their body sizes, geckos seem to select their shelters considering specific microhabitat characteristics surrounding them that may provide thermoregulatory and/or antipredator profits.
Menelaos Kavouras, Emmanouil E. Malandrakis, Eleni Golomazou, Ioannis Konstantinidis, Ewout Blom, Arjan P. Palstra, Konstantinos Anastassiadis, Panagiota Panagiotaki and Athanasios Exadactylos
Common sole (Solea solea) aquaculture production is based mostly on wild-caught breeders. Recently, the successful reproduction of first-generation fish that were reared in captivity was accomplished. A consistent good quality and quantity of produced eggs throughout the year, and of next-generation broodstock, is important for reducing the overall cost of production. Hox genes play a pivotal role in normal embryonic development and alterations of their temporal expression level may be important for egg viability. Expression profile analysis of five hox genes (hoxa1a, hoxa2a, hoxa2b, hoxb1a and hoxb1b) involved in early embryonic development and of hoxa13a, which is involved in late stages, was carried out. Results revealed a premature and/or maternal expression of hoxa13a in sole embryos, and the detection of hoxa2a and hoxa2b genes as members of paralog group 2. Principal Component Analysis of hox gene expression in 54 ± 6 hours post fertilization embryos coming from wild-caught broodstock and a first-generation one reared in the hatchery, unveiled that these broodstocks are clearly distinct. In addition, their pairwise comparison revealed significant differences in the expression levels of hoxb1a and hoxb1b genes. Hox gene regulation during embryonic development could give valuable insight into rearing sole broodstocks with different origin in concert, and also into gaining a steady mass production of eggs, either in quality or quantity, all year round.
Christophe Dufresnes and Íñigo Martínez-Solano
While estimates of genetic divergence are increasingly used in molecular taxonomy, hybrid zone analyses can provide decisive evidence for evaluating candidate species. Applying a population genomic approach (RAD-sequencing) to a fine-scale transect sampling, we analyzed the transition between two Iberian subspecies of the common midwife toad (Alytes obstetricans almogavarii and A. o. pertinax) in Catalonia (northeastern Spain), which putatively diverged since the Plio-Pleistocene. Their hybrid zone was remarkably narrow, with extensive admixture restricted to a single locality (close to Tarragona), and congruent allele frequency clines for the mitochondrial (13 km wide) and the average nuclear genomes (16 km wide). We also fitted clines independently for 89 taxon-diagnostic SNPs: most of them behave like the nuclear background, but a subset (13%) is completely impermeable to gene flow and might be linked to barrier loci involved in hybrid incompatibilities. Assuming that midwife toads are able to disperse in the area of contact, we conclude that these taxa experience partial reproductive isolation and represent incipient species, i.e. Alytes almogavarii and Alytes obstetricans. Interestingly, their evolutionary age and mitochondrial divergence fall below the thresholds proposed in molecular systematics studies, emphasizing the difficulty of predicting the outcome of secondary contacts between young lineages entering the grey zone of speciation.
Heidi M. Thomsen, Thorsten J.S. Balsby and Torben Dabelsteen
Many species of parrots live in fission–fusion social systems, characterised by frequent changes in flock composition. In these systems, the ability to selectively choose flock members is essential in order to maximise individual fitness. As a result, most species of parrots have individual distinctive contact calls that mediate the formation of groups during fission and fusion events. However, in vocal interactions during fission and fusion events, individuals will modify the fine-scale structure of their contact calls in a manner that sometimes will result in imitation of the contact calls of another individual, potentially altering or weakening the individual distinctiveness of contact calls. This presents parrots with an interesting dilemma. Here we present a study investigating the effect of vocal modification during interactions, including vocal imitation, on the individual distinctiveness and sex-specific differences of contact calls from ten captive bred peach-fronted conures (Eupsittula aurea). In order to determine if vocal individual- and sex distinctiveness persists in contact calls that are modified to that of another individual, we compared nine acoustic parameters from spontaneous (baseline) contact calls and contact calls emitted as response to a playback stimulus. Although modified, all acoustic parameters remained individually distinctive when the focal individuals interacted with the playback stimulus. These results provide a strong basis for discriminating between calls from different individuals across several social contexts, which could play an important role in mediating selective associations between individual peach-fronted conures during fission and fusion events.
Amalia Segura and Pelayo Acevedo
Collection for the pet trade has been considered one of the major threats to the Mediterranean spur-thighed tortoise Testudo graeca, since it modulates the size and structure of the species’ populations and, therefore, their demography. Maamora forest is one of the most suitable habitats for this species. The proximity of the forest to Rabat indicated the possibility of these tortoise populations being particularly sensitive to over-collecting. Population demography was studied in four populations, in protected and unprotected areas in Maamora forest. The results showed significant differences as regards population size and structure between protected and unprotected areas. They specifically highlighted: i) higher density (23-17 indiv · ha−1) balanced populations in the protected areas, in which young adults were predominant, ii) a higher body condition in the protected areas, especially the females, and iii) a low density (5.5 ind · ha−1) more unbalance population in the unprotected areas, in which older females and younger males were predominant. In addition, a survey carried out by interviewing local adults (
Young precocial birds develop a preference for an imprinting object by mere visual exposure to it in the absence of conventional physiological reinforcement. The lack of the necessity of conventional reinforcement for imprinting, however, does not mean that such reinforcement is unimportant. The evidence presented here shows that an imprinting object rapidly acquires high attractiveness to young chicks when it is associated with food provisioning. Domestic chicks, Gallus gallus domesticus, were first exposed to two different imprinting objects in the absence of any reinforcement. Subsequently, two groups of chicks received a single feeding session wherein they were provided with prey from one of the imprinting objects. A third group served as a control in which the chicks were exposed to one of the imprinting objects and prey delivery in an unpaired way. Finally, all chicks received two choice tests to assess their preferences for the two imprinting objects. The chicks that received food from an imprinting object strongly preferred that object to the alternative familiar-only object, and preferred the familiar-only object to a novel object. The control group did not show any preference between the two imprinting objects, but preferred the unpaired imprinting object to a novel object. These results suggest that primary-need reinforcers such as food contribute to increasing the attractiveness of an imprinting object by promoting rapid associative learning.
Tom A. Weggelaar, Daniël Commandeur and Joris M. Koene
Post-copulatory sexual selection research tends to focus on the numerous adaptations that have evolved to increase the chances of donated spermatozoa fertilizing oocytes. Even though fertilization obviously directly depends on the presence of sufficient, viable spermatozoa, the quantification of the sperm transfer process itself has not received the attention it deserves. Here, we present experimental work on a simultaneously hermaphroditic snail in combination with a review of the literature focussing on the relationship between the duration of copulation and the number of sperm that are transferred. Based on classical work, this relationship is often assumed to be linear, but as we show here this need not be the case. Both our experimental data and the reviewed literature indicate that there are clear instances where the process of sperm transfer is not a linear process, i.e., longer copulation duration does not necessarily imply more transfer of sperm. As we point out, there seems to be a bias in the literature towards investigating this in insects, but other animal groups in which this has been investigated do show similar relationships. To conclude, we discuss how the specific patterns of sperm transfer that have been reported can be biologically interpreted and we caution that simply using copulation duration as a proxy for the number of sperm transferred can be misleading.
K. Wojczulanis-Jakubas, J. Plenzler and D. Jakubas
Behavioural contagion is a curious phenomenon of human social life which is believed to facilitate group living. It has also been demonstrated in animals that some behaviours may be contagious: how widespread this phenomenon is remains unclear, as only a few species have been tested. In this context, we examined whether three behaviours commonly exhibited by moulting southern elephant seals (Mirounga leonina): “sneezing”, scratching and yawning could be contagious. Using the randomization approach, we found this to be the case in general for all the behaviours, although the pattern was not that obvious or present at all for all the social groups. This indicates there is a potential for social contagion but the issue is complex. Despite limitations associated with observational study on small-size social groups, this is the first report of contagious behaviours in marine mammals and is to encourage further investigation.
Joseph M. Pich, A.J. Belden and Bradley E. Carlson
Temperament traits are often measured under artificial conditions, which may not necessarily predict behaviour in naturalistic contexts. A reliable behavioural assay should yield similar results as tests performed under alternative conditions, but this is not frequently evaluated in free-living animals. Eastern box turtles (Terrapene carolina) exhibit individually consistent boldness behaviour in an artificial confinement assay, so we tested turtles repeatedly using the confinement assay along with a simulated predator attack assay. Turtles that were bolder during the confinement assay tended to also be bolder after the simulated predator attack, suggesting temperament is not context-specific. Bolder turtles also employed active defences (e.g., fleeing or biting) more often, demonstrating that different behavioural measures yield similar findings. Boldness in these turtles appears to be a generalized temperament trait, and similar procedures could be used in other species as well to establish the sensitivity of behavioural assessments in the field to assay conditions.
Cy L. Mott, Haris Dzaferbegovic, Shelby R. Timm and Howard H. Whiteman
Kin selection in larval amphibians is hypothesized to increase survival to metamorphosis. While kin selection may benefit amphibians with obligate metamorphosis, increased survival within sibships may exert fitness costs on facultatively paedomorphic species, such as increased competition among kin. Consequently, it is unclear whether such species should engage in kin selection. We investigated kin selection in a facultatively paedomorphic salamander, Ambystoma talpoideum, using laboratory behavioural trials and microcosm experiments. Individuals were most aggressive towards familiar siblings, and full-sibship groups incurred more injuries than mixed-sibship groups; however, familiar siblings ultimately exhibited higher survival. Thus, while short-term responses appeared to reflect the hypothesized costs of kin recognition, long-term patterns of survival did not support this hypothesis. The inconsistencies between results suggest that short-term studies may not capture ontogenetic variation in kin selection, and that long-term studies are needed to better test the hypothesized effects of kin selection on survival and metamorphosis.
Rebeca A.P. Sampaio, Danielle O. Moreira, André M. de Assis, Sérgio L. Mendes and Andressa Gatti
Most plant species in the Atlantic Forest invest in zoochory as a dispersal mechanism and many depend on vertebrates to fulfill that role. The sizes of fruits and seeds are limiting factors in interactions between vertebrates and plant species. For example, plants that produce fruits with large seeds are more dependent on large frugivorous vertebrates for dispersal. We used camera traps to observe the interactions between frugivorous vertebrates and two large seed-producing plants of the genus Spondias in the Tableland of the Atlantic Forest of Espírito Santo, Brazil. Between 2015 and 2016 (622 camera days), we recorded 17 species of frugivorous vertebrates potentially ingesting fruit at the studied sites. Among the species recorded, only the lowland tapir (Tapirus terrestris) was observed interacting directly with S. venulosa and S. macrocarpa. Our analysis indicates that the type of interaction depends on the body size of the vertebrate species, meaning that direct interaction with fruits of Spondias is commonly performed by medium and large vertebrates, such as spotted pacas, agoutis, and tapirs. Our study highlights the importance of these vertebrates in the forest remnants of the Atlantic Forest Tableland, such as the Linhares-Sooretama forest complex, for conservation and regeneration of plant communities.
Stefano S.K. Kaburu, Brianne Beisner, Krishna N. Balasubramaniam, Pascal R. Marty, Eliza Bliss-Moreau, Lalit Mohan, Sandeep K. Rattan, Małgorzata E. Arlet, Edward R. Atwill and Brenda McCowan
Time is a valuable but limited resource, and animals’ survival depends on their ability to carefully manage the amount of time they allocate to each daily activity. While existing research has examined the ecological factors affecting animals’ activity budgets, the impact of anthropogenic factors on urban-dwelling animals’ time budgets remains understudied. Here we collected data through focal animal sampling from three groups of rhesus macaques in Northern India to examine whether interactions with humans decrease macaques’ resting and social time (time constraints hypothesis), or whether, by contrast, foraging on anthropogenic food, that is potentially high in calories, leads macaques to spend more time resting and in social interactions (free time hypothesis). We found that macaques who interacted more frequently with people spent significantly less time resting and grooming, supporting the time constraints hypothesis. We argue that these time constraints are likely caused by the unpredictability of human behaviour.
Li Gong, Xiaoyu Kong, Hairong Luo, Shixi Chen, Wei Shi and Min Yang
Eukaryotic nuclear ribosomal DNA (rDNA) typically evolves in a concerted manner, in which hundreds of rDNA sequences within species show little or no variations, whereas the sequences of different species diverge. There are few studies of the internal transcribed spacer regions (ITS1-5.8S-ITS2) in teleostean fishes and only one report on flatfishes. Here, we reported the discovery of two types of highly divergent ITS1-5.8S-ITS2 rDNA sequences (Type A and B) in the genome of the Bloch’s tonguesole, Paraplagusia blochii. These sequences mainly differ in sequence length, secondary structure, and minimum free energy. According to the potential features of pseudogenes, Type B sequences are speculated to be putative pseudogenic ITS regions. Cluster analyses also supported two major clades that corresponded to the sequence type. To the best of our knowledge, this is the first report of the ITS regions of tonguefish, and may therefore provide useful information for future studies of the rDNA of flatfishes as well as the patterns of rDNA evolution in teleostean fishes.