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Abstract

Ecological niche modelling provides a useful tool to measure niche properties such as niche breadth, niche overlap and niche conservatism among genetic lineages, with relevant implications for conservation. The Mediterranean pond turtle Mauremys leprosa occurs on both sides of the Strait of Gibraltar over most Iberia and the Maghreb Region of north-western Africa, where it shows a complex genetic structure as the result of Pleistocene climatic oscillations and the particular geographical features of this region. We analyzed the overlap of the climate niche of genetic lineages and sublineages of Mauremys leprosa, based on confirmed records across the known geographical range of the species. We also compared the accuracy of environmental niche models obtained by splitting the two lineages into subunits and lumping across lineages. Results revealed an overall niche overlap between the two main lineages and among most sublineages, indicating no relationship between genetic variation and niche divergence. Likewise, the environmental niche modelling revealed an extensive geographical overlap of climatic suitability between the two lineages. However, some ecological differentiation occurs for some sublineage pairs, in particular involving a sublineage whose occurrence corresponds to a particular morphotype – the Sahara blue-eyed pond turtle – which occupies very isolated habitats along the Draa basin in Morocco. These populations are currently threatened by fragmentation of habitats, drought and water salinization. This study will help assessing more effectively the impacts of ongoing climate change on Mauremys leprosa that along with local human activities are likely to increase in the southernmost limit of its distribution.

In: Amphibia-Reptilia

Abstract

When individuals groom or preen one another (allopreening), vulnerability and physical access allow for information about hierarchy and bonds to be exchanged, in addition to basic health benefits. During these interactions, individuals may also self-direct grooming/preening (autopreening). We investigate autopreening in a cooperatively breeding passerine bird, the Arabian babbler (Turdoides squamiceps) in the specific context of allopreening interactions. Auto- and allogrooming (the mammalian analogue behaviours) may occur in sequence together, with some species socially facilitating allogrooming by autogrooming. We here consider the possibility of similar associations between autopreening and allopreening. Using a two-year database of 35 individuals in 8 social groups, we assessed the social factors that predict the occurrence of autopreening and its timing in the context of allopreening dyad formation. We ask if there is a social dimension to this behaviour, and specifically find evidence that it may represent displacement and/or subordinate behaviour. The relative age of individuals in preening dyads and the behaviour of recipients prior to social approach significantly predicted the behaviour of recipients as the preening dyad was formed: recipients were less likely to autopreen before approaching older actors to begin an allopreening bout. When recipients autopreened, actors were more likely to make the approach. Recipients that did not autopreen or otherwise conspicuously display were significantly more likely to approach the actor without first autopreening. We suggest that autopreening in these bouts is a socially modulated behaviour representative of uncertainty and/or subordination.

In: Behaviour

Abstract

The Lesser Sunda Archipelago consists of hundreds of oceanic islands located in southern Wallacea. The Sunda ratsnake, Coelognathus subradiatus, is endemic to the Lesser Sundas and is found on most of the major islands. Mitochondrial DNA was sequenced from snakes representing five of the major islands revealing that levels of sequence divergence between islands range from 2-7%. Phylogenetic analyses recover what can be interpreted as a three-lineage polytomy consisting of lineages from 1) Alor, 2) Sumbawa + Flores, and 3) Timor + Wetar. The archipelago was colonized from the Sunda Shelf ∼7 Myr with subsequent population divergence occurring ∼4.5 Myr, likely resulting in insular species formation.

In: Amphibia-Reptilia

Abstract

Based on genetic and morphological evidence, Senczuk et al. (2019) formally raised the Podarcis populations from the Western Pontine Islands, previously classified as several subspecies of P. siculus, to species rank, i.e. Podarcis latastei (Bedriaga, 1879). This taxonomic change was not accepted in the checklist of the European herpetofauna by Speybroeck et al. (2020), recently published on Amphibia-Reptilia. In this note we respond to the reasons given by Speybroeck and colleagues and support the validity of Podarcis latastei as an endemic Italian species.

In: Amphibia-Reptilia

Abstract

We aimed to discern the seasonal movement patterns, home range sizes, and microhabitat associations of subadult Macrochelys temminckii in a West Tennessee population. Because this population was previously monitored (i.e., telemetry and habitat use) as juveniles after the initial release in 2005, studying the movement ecology and habitat use of the same released cohort 12 years later allows for unique comparisons between hatchling and subadult ecology. We used radio telemetry to collect movement and microhabitat data of 16 subadult M. temminckii during one year. Our results suggest that seasonal and ontogenetic variation in movement patterns and habitat selection occur within a cohort of M. temminckii. Compared to juveniles, subadults used deep slough areas with high overstory tree cover and had larger home ranges (100% minimum convex polygons [MCP]). Additionally, as subadults, the mean distance moved (m) varied among seasons and furthest during summer. Subadults used deeper water, with higher temperatures and significantly more tree canopy cover, than random locations. Overall, the home range estimate for subadults (mean MCP ± SE; 1.64 ± 0.57 ha) was greater than for juveniles (0.044 ± 0.021 ha). These home-range estimates and habitat usage patterns were similar to subadults in other studies. The seasonal and ontogenetic variations suggest that habitat heterogeneity is critical to sustain populations of introduced M. temminckii.

In: Amphibia-Reptilia

Abstract

Wild female chimpanzees typically migrate to a neighbouring community at the onset of sexual maturity, a process that can be dangerous and unpredictable. To mitigate the risk of rejection in the new community, immigrants may employ several behavioural strategies. During the integration of two chimpanzee females at Royal Burgers’ Zoo (Arnhem, The Netherlands) one of the immigrant females rapidly copied a local tradition — the crossed-arm walk — which has been present in the group for over 20 years. She copied the behaviour after meeting only one resident female, and showed the behaviour frequently throughout a 6-month observation period following the introduction. The other immigrant female never adopted the crossed-arm walk, highlighting the variation in behaviour by immigrants upon integration, as well as the potential associated consequences: in a separate observation period 2 years later, the female who copied the local tradition appeared more socially integrated than the other immigrant female.

In: Behaviour

Abstract

This anecdotal observation details the response of long-tailed macaques (Macaca fascicularis) to a heterospecific carcass. The subgroup of macaques we were following abruptly changed their direction of travel upon reaching a tree line while displaying silent vigilance behaviour. We later discovered a dog carcass in the area and concluded their behaviour may have been in response to the smell of that carcass. The carcass was not visible from the response point at the tree line due to its distance from that point (approximately 30 meters) and the uneven and densely vegetated terrain between. The macaques were therefore most likely responding to scent cues from the carcass. We suggest the observed vigilance behaviour is excessive under a strictly pathogen-avoidance explanation and may be understood as a response to a cue of potential predation risk. We review alternative explanations and suggest future research on nonhuman primate heterospecific carcass avoidance is necessary to fully assess the potential relation to perceived risk of predation.

In: Behaviour

Abstract

The relative influence of climatic and social factors on sex-specific variation in reproductive behaviour remains poorly understood. Here, we examine the influence of multiple climatic cues in combination with a social cue on the reproductive behaviours of males and females in a terrestrial breeding toadlet (Pseudophryne coriacea). Over a 115-day breeding season, arrival patterns of each sex, and male calling activity, were recorded daily, while climatic variables were logged continuously. Multivariate analysis showed that arrival of males at the breeding site, as well as male nightly calling activity, were most strongly influenced by a climatic variable (rainfall). By contrast, female arrival was strongly correlated with a social variable (male calling activity), with abiotic conditions having no influence, other than a moderate influence of lunar phase (lunar illumination). These results suggest that cues used for breeding are sex specific and provide new evidence that combinations of climatic and social cues can be integrated into breeding decisions.

In: Behaviour

Abstract

We tested for dietary choices of foods varying in nutrient composition by cottontail rabbits on two college campuses in midwestern USA. We quantified choices among pellets of varying nutritional quality at artificial food patches. Dietary choices differed between seasons and locations. Spring giving-up densities (GUDs: food left behind) did not show differences in food choices and were lower than summer GUDs. In Appleton, the cottontails favoured both high protein and fibre pellets, whereas the medium protein and fibre pellets were favoured in Chicago. The cottontails maintained their choice of high protein, high fibre pellets at three spatial scales. The cottontails varied food intake to balance their protein, salt and fibre needs at different times and locations. Studying dietary choices and the effect of resource quality on foraging responses by urban wildlife provides a useful tool to study ecological interactions and can help minimize damage in urban environments such as parks.

In: Behaviour