Le CEREEP-Ecotron IleDeFrance est partenaire du projet ANAEE-Service (Analyse et Experimentation sur les Ecosystèmes) lauréat de l'appel d'offre des Infrastructures nationales en biologie-santé. L'annonce des lauréats a été faite le mardi 7 février 2012 au Ministère de la Recherche par Monsieur Laurent Wauquiez en présence du directeur du centre qui a représenté l'infrastructure nationale. Le projet ANAEE-Service vise à doter la France d'un réseau intégré de plateformes expérimentales, analytiques et numériques dédiées à l'étude des écosystèmes continentaux, terrestres et aquatiques. Doté de 14 M€ d'investissement et de fonctionnement jusqu'en 2020, ce projet permettra de construire l'infrastructure en France et contribuera à la dynamique Euopéenne d'ANAEE qui est actuellement en phase préparatoire du forum ESFRI. Le CEREEP-Ecotron IleDeFrance contribue comme partenaire au projet en y asssociant la plateforme PLANAQUA (Plateforme nationale d'écologie aquatique) et en développant l'Ecotron IleDeFrance. Notre centre se retrouve ainsi associé avec d'autres plateformes du CNRS, de l'INRA et de partenaires universitaires dans la seule infrastructure nationale de biologie dédiée à l'étude des écosystèmes.

 

Plus d'information sur le site web du centre: www.foljuif.ens.fr 

A major isue in evolutionary ecology is "costs of reproduction", i.e. the fact that females investing more in reproduction may suffer from reduced growth, survival or reproduction in the future. In lizards, it is well known that a high reproductive effort can decrease locomotion and performances in females, but relatively little is known about mechanisms controlling the reproductive effort of a female. In a forthcoming paper, we demonstrate that litter size is controlled prior to mating in the common lizard because females ovulate spontaneously even in the absence of mates. Spontaneous ovulation implies strong selection on females to fertilize their eggs and select the best males during mating and therefore has important consequences for sexual selection in this species.

 

Our group has published the first experimental test of the silver-spoon effect on natal dispersal, according to which dispersers born under more favourable conditions are more likely to find and eventually settle in high quality habitats. To do so, we used root voles, a small mammal from boreal and northen temperate environments, as model systems in field experiments. Root voles are well-known for their flexible dispersal strategies and the quality of their habitat can be manipulated in the field. To create favourable conditions for juvenile root voles, we raised pups in small litters inside the laboratory during the lactation period and compared these pups with others raised in enlarged litters. In accordance with our expectations, we found that youngs raised in small litters were bigger and in better conditions than youngs raised in larger litters. We then designed a field study to investigate the interactive effects of individual condition and habitat quality on the different stages of natal dispersal. Contrary to expectation root voles in “high”-condition did not preferentially settle in high-quality habitats. Yet, individuals avoided in general settling in low-quality patches. This neatly demonstrates that immediate effects of habitat quality can override potential long-lasting effects of physical condition on dispersal behaviour. Our results have been published in a latest issue of Journal of Animal Ecology.