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ADAPTATIONS OF THE APERTURE IN TERRESTRIAL GASTROPOD-PULMONATE SHELLS by EDMUND GITTENBERGER (Institute of Evolutionary and Ecological Sciences, P.O. Box 9516, NL 2300 RA Leiden, The Netherlands) ABSTRACT In gastropod shells, the aperture is the most vulnerable part. Various structures evolved

In: Netherlands Journal of Zoology
The phylum Apicomplexa is characterized by the unique cell organisation of the zoites, the infective stages of unicellular parasites previously designated as Sporozoa. Apicomplexa includes Coccidian and Hematozoa well known for human and veterinary diseases they cause, such as malaria, toxoplasmosis, babesiosis, coccidiosis, and the large group of Gregarines, the early branching Apicomplexa. Gregarines are parasite of invertebrates and urochordates and they performed an extraordinary radiation from the marine and terrestrial hosts known from the Cambrian biodiversity explosion. After the basic publication in the Traité de Zoologie by Grassé in 1953, this second edition updates the knowledge with information provided by new technologies such as electron microscopy, biochemistry and molecular biology and to enlighten their high diversity of adaptation to invertebrate hosts living in a diversity of biotopes. The extracellular development of Gregarines, the considerable diversification of their cell cortex, their wide distribution in Annelids, Crustaceans, Echinoderms, Myriapods or Insects with about hundred thousands of species contribute to the understanding of many biological aspects of the pathogenic Apicomplexa. Since 1953, taxonomical reviews on Gregarines were published in the Illustrated Guide of Protozoa. In this supplement, there is a special emphasis on the hosts.

Contributors include: Stuart Goldstein, Ryoko Kuriyama, Gérard Prensier, Jiri Vavra, Lawrence Howard Bannister, Jean François Dubremetz.

Without the financial support of academic and non-profit organisations the edition of this volume would not have been possible. Many thanks to the LabEx BCDiv Biological and Cultural Diversities: Origins, Evolution, Interactions, Future, Groupement des Protistologues de Langue Francaise (GPLF), Société des Amis du Muséum, Société Française de Parasitologie for their generous grants.

Author: David Reznick

LIFE HISTORY EVOLUTION IN GUPPIES: A MODEL SYSTEM FOR THE EMPIRICAL STUDY OF ADAPTATION by DAVID REZNICK (Department of Biology, University of California, Riverside, CA 92521, USA) ABSTRACT I have used a diversity of observations and experiments to evaluate whether or not guppy life histories

In: Netherlands Journal of Zoology

, to an optimal fit between 'design' and ecology. However, the adaptation process may be impeded or slowed down by several constraints or trade-offs between conflicting functions. This is frequently observed by ecomorphological studies focusing on lower taxonomic levels: form-function relationships get

In: Netherlands Journal of Zoology

-eating pigeons which achieve the fine adjustment by direct regulation of the transport mechanism through the membrane of the microvilli. KEY WORDS: functional morphology, intestinal tract, adaptation, specialisation. INTRODUCTION Viscera in General This section of the congress contains a spectrum of up

In: Netherlands Journal of Zoology

possibility that the bird tendons studied work as springs and the supposed evidence of a different mechanical behaviour of some tendons, because of particular adaptative reasons, are discussed. KEY WORDS: tendons, legs, birds, stresses, safety factors, scaling, adaptation. INTRODUCTION In the last few years

In: Netherlands Journal of Zoology

the PMS among catfish. For each morphological transformation, the way it was realised is hypothesized and the probable adaptive advantage it brings is analysed. KEY WORDS: adaptation, catfish, functional morphology, palatine-maxillary system, macroevolution, maxillary barbels, Siluriformes

In: Netherlands Journal of Zoology

The systematic value of the middle-ear ossicles, in particular the malleus, has been long recognized for diverse groups. We present systematic work on the characters of the middle-ear ossicles of pinnipeds, focusing on until now poorly studied Southern Hemisphere species. Mallei were extracted from 16 specimens of pinnipeds belonging to five austral and one boreal species of Phocidae and two austral species of Otariidae. Several characters used in this study have been described previously, and some were here modified. Three new characters are here defined and analysed. All characters were mapped onto the phylogeny. Our character analysis shows the transformations that have occurred in the evolution of middle ear ossicles in pinnipeds and identifies diagnostic features of many of its clades. Beyond the identification of specific changes within eachclade, our study of pinniped ossicle evolution documents the occurrence of anatomical convergences with other groups of mammals that live in an aquatic environment, as has occurred in other organ systems as well.

In: Contributions to Zoology

effects of toxic chemicals must be seen in the context of the complex of adaptations of animals to the environment. KEY WORDS: adaptation, biotransformation, glutathion-S-transferase, heavy metals, Isopoda, life-history, Lumbricidae, polycyclic aromatic hydrocarbons. INTRODUCTION Variability is one of the

In: Netherlands Journal of Zoology
Author: Edward Gaten

This paper addresses the use of eye structure and optics in the construction of crustacean phylogenies and presents an hypothesis for the evolution of superposition eyes in the Decapoda, based on the distribution of eye types in extant decapod families. It is suggested that reflecting superposition optics are symplesiomorphic for the Decapoda, having evolved only once, probably in the Devonian. Subsequent loss of reflecting superposition optics has occurred following the adoption of a new habitat (e.g. Aristeidae, Aeglidae) or by progenetic paedomorphosis (Paguroidea, Eubrachyura).

In: Contributions to Zoology