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Vingt ans après la première conférence de Rio, qu'est devenue la proposition de conduire nos sociétés vers un développement durable ? Adopté par les uns, utilisé comme faire-valoir par les autres, ce concept de développement durable est souvent vidé de son sens. Or, l'impact exponentiel des activités humaines sur les ressources naturelles, la santé des populations et le milieu exige d'expliquer ce qu'il est précisément. Qu'est-ce que le développement durable aujourd'hui ? Qu'en est-il de la disponibilité des ressources et de l'usage que nous en faisons ? Dans le domaine de l'eau, du climat, des sols, de la biodiversité ? En milieu rural, sur le littoral ou encore en milieu urbain, là où la majorité de la population va vivre d'ici 2050, comment consommons-nous au fil du temps, à travers les territoires? Quelles incidences les activités humaines ont-elles sur les ressources, sur la santé des populations et sur le milieu lui-même ? Les relations entre l'humanité et l'environnement doivent-elles évoluer ? Autant de questions posées à des scientifiques qui éclaircissent la complexité des interactions entre les systèmes et proposent des solutions pour un avenir sur le long terme. De nos écosystèmes à nos modes de consommation, des risques naturels aux nouvelles technologies ou aux pollutions, des usines du futur au traitement des déchets, Le développement durable à découvert informe, explique, partage tout ce que la science actuelle est capable d'apporter au défi majeur du XXIe siècle : comment mieux comprendre la complexité des enjeux qui nous concernent tous et assurer le développement de l'humanité sans détruire son biotope. Économistes, physiciens, sociologues, agronomes, écologues... plus de 150 chercheurs se sont mobilisés pour associer leur expertise à leur regard critique et décrire, comprendre, modéliser, imaginer, illustrations et schémas à l'appui, les outils destinés à construire les sociétés équitables de demain.(résumé 4e de couv)

Aujourd’hui, l’incidence des activités humaines sur le monde vivant est telle, que la biodiversité se retrouve engagée dans une crise majeure de son histoire. Face aux changements environnementaux, les organismes et les communautés disposent pourtant de plusieurs capacités de réponses. Conditions et vitesses d’adaptation L’adaptation des espèces en réponse aux changements planétaires peut s’entendre de façon très restrictive, comme l’évolution de la composition génétique des populations, en r...

International audience; In their letter, Dekel et al. (1) comment on our recent findings on the origin of house mice (Mus musculus domesticus) 15,000 y ago, ecological impacts of the first settled hunter-gatherers, and insights that this study provides on early domestication processes (2). They maintain that mice were parasitic with humans rather than commensal, and attracted by refuse and feeding opportunities in nomadic and sedentary hunter-gatherer settlements. Dekel et al. (1) contrast "negative" interactions with mice with the benefit that hunter-gatherers obtained from early interactions with wolves and wild boar. These arguments do not conform to empirical results from our study on mice (2), recent research on wild boar domestication (3), or theoretical expectations regarding commensal and preagricultural human/animal interactions (4-6). We do not argue for mutualism and domestication. The question of whether house mice were commen-sal with humans or parasitic is an interesting issue. However, Schwarz (7) argued that parasitism is not an appropriate description of human/mouse relations because mice do not depend on human hosts for their existence. Neither do the negative effects of mice (food consumption and disease transmission) involve direct impacts, sensu stricto. Our record on Levantine mice (2) offers rare empirical archaeological evidence demonstrating both positive and negative ecological effects on wild populations, which complies with formal definitions of commensalism in ecological theory (6, 8). We demonstrate absolute population shifts in mice with oscillations in mobility among Levantine hunter-gatherers preceding intensive Neolithic cultivation (ca. 15,000-11,500 B.P.). Still, current thinking on questions of animal domestication goes considerably farther than matching of species with categories of human/animal interaction. Niche construction paradigms examine intentional and unintentional cultural influences and the evolutionary trajectories of species that share human environments (4, 5, 9), providing a framework for understanding the mutable nature of commensal and mutualistic relationships characteristic of domes-tication (10). Our results demonstrate that early for-ager sedentism and its increasing ecological impact on ancient landscapes triggered new forms of interaction with species such as mice. It is likely that changing settlement habitats influenced wolves and wild boar, but in different ways. It was not merely the availability of "human waste" that provided a triggering mechanism for incipient domestication (1). It was rather the changing settlement ecology due to longer term and more intensive human occupation , as compellingly proposed by Edgar Anderson's dump-heap hypothesis (4). The influence of the built environment on intraspecies and interspecies social interactions and predation and the variable role of human intentionality was culturally significant. Our study of mice binds these strands of theory together, establishing that early sedentism marked a significant turning point in human ecological interactions, ushering in an era of steadily increasing anthropogenic ecosystem transformation and changing human/animal relations.

How evolution can be channeled by intrinsic processes such as genetic and developmental networks is a key issue in evolution. Studying the phenotypic variation in a population can shed light on these constraints, because this variation, being the product of these genetic and developmental processes, is the target of both selective screening and random sampling. It could thus act as a “line of least resistance to evolution”. Based on morphometric analysis of molar and mandible shape in several fossil lineages and modern groups of murine rodents, we illustrate here the questions that can be addressed based on this framework. The role intrapopulational variation as line of least resistance to evolution is validated on several lineages. The existence of such preferential direction of evolution can contribute to explain cases of parallel evolution. The underlying mechanisms can be the sharing of similar genetic/developmental pathways but also common functional constraints limiting the range of phenotypic variation to be explored. Comparing directions of intrapopulation variance to the course of interpopulation evolution can thus be of help to bridge several evolutionary levels and contribute to an integrated vision of the phenotypic evolution. Download the complete "Yellow Book" on "Virtual Morphology and Evolutionary Morphometrics in the new millenium".

International audience; “Protocols for field and laboratory rodent studies” is a publication generated by the CERoPath project (Community Ecology of Rodents and their Pathogens in a changing environment, www.ceropath.org) funded by the French Ministry of Research from 2008 to 2011 (French ANR Biodiversity ANR 07 BDIV 012). This book was written and compiled by the various partners directly involved either in the trapping of rodents or in the analyses of samples for rodent or macro- and micro-parasites identification. These protocols summarize the techniques that we developed while studying wild rodents, during almost ten years. It aims to providing accurate and practical knowledge and advice for future research on rodents, keeping in mind that this information would have been precious to all of us when we started our studies. Requirements for trapping and manipulating rodents differ regarding the objectives of the studies. Some observations can be made without capturing animals: by identification of foot tracks, feces, damage to crops or objects, burrowing activity, by using camera or video traps, by recording acoustic signatures with ultrasounds detectors, etc. These techniques have enabled identification of unknown species and allowed collection of information on the ecology of species (seasonal migrations, daily ranges, density). However trapping may be necessary in some cases. First to describe a new species, some invasive samples (such as hairs) can be taken for genetic analysis and some measurements can be performed on a live rodent lightly anaesthetized. Second, for a medical survey, a small volume of blood can be obtained using methods that minimize stress and pain for the animal. Third, longitudinal ecological studies may also require live trapping to mark (ear tag, toe clip, etc.) or follow (radio transmitter, GPS collar) animals. We placed emphasis on providing colorful illustrations for a better interpretation. Consequently, these protocols show some pictures of dead animals since sacrifice is necessary for some specific research purposes. Nevertheless we tried to present alternatives to sacrifice wherever possible.

International audience

International audience; The role of chromosomal rearrangements in disturbing reproduction in hybrids between karyotypically differentiated groups is fairly well documented. However, the effect of chromosomal changes at other phenotypic levels is rarely considered. In Tunisia, natural chromosomal hybrids of the house mouse exhibit developmental instability, suggesting that a high karyotypic heterozygosity might also affect developmental processes. If this is true, we predict that, in this species, developmental instability should arise in hybrids between any populations with a high chromosomal differentiation. To test this hypothesis, we compare the results obtained in Tunisian mice with those obtained in the present analysis on Madeiran mice. Both systems of races have similar levels of chromosomal differentiation (nine Robertsonian fusions). Unlike Tunisian mice, hybrids in Madeira display a similar level of developmental instability as parental groups. This indicates that structural heterozygosity per se does not necessarily impair developmental stability. It further suggests that chromosomal fusions are not all equivalent in their phenotypic effects, and that the identity of each fusion should be taken into account.

This paper provides a critical analysis of archaeological small mammal collections in the Mediterranean area, from the Late Glacial to the first centuries AD, to validate the presence/absence of the house mouse through zooarchaeological criteria. The results have been synthesized through a diachronic map, whose chronological phases are related to socio-economic and cultural human evolution. The house mouse ( Mus musculus domesticus ) progression in the Mediterranean begins with a quick but limited diffusion in the Eastern Mediterranean Basin achieved around the 8th millennium BC. Until the 1st millennium BC, the invasive process seems to have stopped or drastically slowed, despite the increasing opportunities of passive transport during the Bronze Age. During the 1st millennium BC, there was mass colonization by the house mouse of the entire Western Mediterranean Basin and Northern Europe. We propose to explain this chronological gap in the colonization of the Eastern and Western Mediterranean using source-sink theory considering that the western environments acted like sinks until the first millennium BC. At that time the Western Mediterranean was fully opened to Eastern influences and migrations, and the human pressures on the environment drastically increased. This may have favoured definitively the adaptation of the house mouse to the Western commensal niches.

The divergence in reproductive features and hybrid fertility patterns between two chromosomal races (2 n = 40, 40St, and 2 n = 22, 22Rb) of the house mouse in Tunisia were re-assessed on a larger sample of wild and laboratory-bred individuals than studied hitherto. Results showed that litter sizes were significantly smaller in 40St than in 22Rb mice, contrary to previous analyses. This suggests that variation in litter size between the two chromosomal races is more likely related to selective and/or environmental factors acting locally than to interracial reproductive trait divergence. However, the significantly reduced litter size of F 1 hybrids compared with parental individuals was confirmed, and further highlighted a sex difference in hybrid infertility, as F 1 females produced fewer litters and of smaller size than males. Histological analyses of F 1 and backcrosses showed a breakdown of spermatogenesis in males and a significantly reduced primordial follicle pool in females. The degree of gametogenic dysfunction was not related to the level of chromosomal heterozygosity per se , but a significant effect of two Rb fusions on follicle number was observed in hybrid females. These results suggest that genetic incompatibilities contribute to primary gametogenic dysfunction in hybrids between the chromosomal races in Tunisia.

International audience

A mitochondrial and nuclear gene analysis allowed us to precise the taxonomical position of the two sympatric species of mice known to be present on Cyprus. One of them is the commensal house mouse M. m. domesticus, and the other revealed to be a new taxon that is a sister species of M. spicilegus and M. macedonicus. The new species is equidistant from each of these, the divergence dating around 0.5-1 Myr. Its origin either results from an ancient accidental colonisation of the island or from a recent transportation by the first epipalaeolithic settlers. In this last eventuality, the new species would also exist somewhere else in Asia Minor.

Gündüz, İslam (Balikesir Author), To study the colonization history of the house mouse (Mus musculus domesticus) on the Madeiran archipelago, complete mitochondrial D-loop sequences were obtained for 44 individuals from Madeira, Porto Santo and Ilhas Desertas. Altogether, 19 D-loop haplotypes were identified which formed part of a single clade in a phylogeny incorporating haplotypes from elsewhere in the range of M. m. domesticus, indicating that the Madeiras were colonized from a single source. Similarities between the sequences found in the Madeiras and those in Scandinavia and northern Germany suggest that northern Europe was the source area, and there is the intriguing possibility that the Vikings may have accidentally brought house mice to the archipelago. However, there is no record of Vikings visiting the Madeiras; on historical grounds, Portugal is the most likely source area for Madeiran mice and further molecular data from Portugal are needed to rule out that possibility.