Updated list of active and archived projects and associated articles available at ResearchGate
In my research group, we investigate the developmental plasticity and fitness consequences of behavioral and life history variation inside natural populations of several animal species with a particular focus on lizards and snakes. We are also interested in understanding how this variation influences population dynamics, geographic range and sensitivity of species to climate change and other global change factors. For this matter, we combine observational studies of field populations, laboratory and mesocososm experiments on whole populations, syntheses and theoretical work where we design new population dynamic models.
Functional ecology of ectotherms: linking physiology and behavior with population ecology
Together with colleagues in Paris, Toulouse, Lyon and Chizé, we are pursuing suites of interdisciplinary research projects where we wish to link a detailed description of organism physiology and behavior with a better understanding of their population ecology. We focus on ectotherms, especially lizards, which are ideal models to integrate elements of thermal and water physiology, stress physiology, energetic and behavior into predictive ecological models. Our current work includes glucocorticoid and oxidative stress physiology and the ecology of habitat degradation, biomarkers of population decline and extinction from climate warming, and mechanistic studies of the plasticity in hydroregulation and thermoregulation physiology and behavior.
Dupoué, A., Rutschmann, A., Le Galliard, J-F., Clobert, J., Angelier, F., Marciau, C., Ruault, S., Miles, D.B. and Meylan S. 2017. Shorter telomeres precede population extinction in wild lizards. Scientific Reports 7:16976
Rozen-Rechels, D., Dupoué, A., Lourdais, O., Chamaillé-Jammes, S., Meylan, S., Clobert, J. and J.-F. Le Galliard. 2019. When water interacts with temperature: ecological and evolutionary implications of thermo-hydroregulation in terrestrial ectotherms. Ecology and Evolution 9:10029-10043.
Dupoué, A., Angelier, F., Ribout, C., Meylan, S., Rozen-Rechels, D., Decencière, B., Agostini, S. and J.-F. Le Galliard. 2020. Chronic water restriction triggers sex-specific oxidative stress and telomere shortening in lizards. Biology Letters 16 (2), 20190889.
Life history variation and evolution
Life history results from age and sex dependent variation in reproduction effort, survival and growth strategies. In my group, we study several important life history problems, such as the ontogenic basis of sexual dimorphism in morphology and coloration, the costs of reproduction, the mechanistic basis and fitness consequences of inter-individual phenotypic variation or the determinants of early variation in survival and late variation in performance (i.e., ageing). In the recent past, we have conducted detailed studies of cohort effects due to delayed life history consequences of environmental variation using both natural and experimental populations of a widespread lizard. We used these data to parameterize physiologically structured population models of the common lizard.
Rutschmann, A., Miles, D. B., Le Galliard, J.-F., Richard, M., Moulherat, S., Sinervo, B. and J. Clobert. 2016. Climate and habitat interact to shape the thermal reaction norms of breeding phenology across lizard populations. Journal of Animal Ecology 85(2):457-466.
Dupoué, A., Le Galliard, J.-F., Josserand, R., DeNardo, D., Decencière, B., Agostini, S. and S. Meylan. 2017. Water restriction causes an intergenerational trade-off and delayed mother-offspring conflict in a viviparous lizard. Functional Ecology 32(3):676-686.
Evolutionary ecology of social and non social behavioral traits
We are interested in understanding inter-individual variation in social behaviors (altruism), mating strategies (mate choice and sexual conflicts) and individual temperaments (activity, sociality, boldness, aggression). Our approach is truly interdisciplinary and involves mathematical modeling, field study of variation in behavioral traits and experimental studies of natural and sexual selection on behavioral traits. Our recent studies have addressed complex issues such as how inter-individual variation in behavior correlates with variation in physiology, how density dependence influences selection on animal personality or how does crytic skin coloration influences competition and mate choice in lizards.
Mell, H., Josserand, R., Decencière, B, Artacho, P., Meylan, S. and J.-F. Le Galliard. 2016. Do personalities co-vary with metabolic expenditure and glucocorticoid stress response in adult lizards? Behavioral Ecology and Sociobiology 70:951-961.
Names, G., Martin, M., Badiane, A. and J.-F. Le Galliard. 2019. The relative importance of body size and UV coloration in influencing male-male competition in a Lacertid lizard. Behavioral Ecology and Sociobiology 73: 98.
Extinction mechanisms in small populations
The massive extinction of species and populations is a major concern today. To solve this crisis, we need conservation programs dedicated to the preservation of small populations that are particularly vulnerable. One method widely available to guide such conservation programs is Population Viability Analysis (PVA) – a tool relying on stochastic population theory to estimate the future size and risk of extinction for small populations. However, our understanding of the dynamics of small populations is quite limited and the predictive ability of PVA has been questioned by several researchers. In my group, we challenged the predictive ability of PVA methods by linking population biological theory with experimental studies of extinction dynamics. This allowed us to gain better knowledge of the dynamics of small populations and the mechanisms leading to population extinction. Our main model systems were experimental populations of the common lizard (Lacerta vivipara), but we also did experiments in the past with the root vole (Microtus oeconomus) and the bank vole (Myodes rufocanus).
Gonzalez-Suarez, M., Le Galliard, J.-F. and D. Claessen. 2011. Population and life-history consequences of within-cohort individual variation. The American Naturalist 178(4):525-537.
Rémy, A., Le Galliard, J.-F., Odden, M. and H. P. Andreassen. 2014. Concurrent effects of age class and food distribution on immigration success and population dynamics in a small mammal. Journal of Animal Ecology 83(4):813-822.
Jaffré, M. and J.-F. Le Galliard. 2016. Population viability analyses of plant and animal populations with stochastic integral projection models. Oecologia 182(4):1031-1043.
Evolutionary ecology of dispersal behavior
Dispersal is a key behavior that influences most ecological and evolutionary dynamics. Our current understanding of this behavioral trait suggests that multiple selective pressures are involved in its evolution. However, crucial tests for the role of these selective forces in shaping dispersal strategies are rare. We also lack a clear understanding of the life history correlates of dispersal within and between species. In my group, we used experimental approaches to investigate the plasticity of this behavior, as well as the potential selective pressures acting on dispersal. To do so, we focused on two vertebrate species – the common lizard (Lacerta vivipara) and the root vole (Microtus oeconomus) – as well as on a soil organism, the springtail Folsomia candida. Our research demonstrated that family dynamic, and in particular competition among relatives, can have a strong effect on dispersal behavior. More recently, we have shown that intrasexual competition among females and female dominance are key determinants of the settlement success in a small rodent.
Le Galliard, J.-F., Rémy, A., Ims, R. A. and X. Lambin. 2012. Patterns and processes of dispersal behaviour in arvicoline rodents. Molecular Ecology 21(3):505-523.
Stevens,V., Whitmee, S., Le Galliard, J.-F., Clobert, J., Böhning-Gaese, K., Bonte, D., Brändle, M., Dehling, D., Hof, C., Trochet, A. and M. Baguette. 2014. A comparative analysis of dispersal syndromes in terrestrial and semi-terrestrial animals. Ecology Letters 17(8): 1039-1052.
Gallardo Ruiz, M., Le Galliard, J.-F. and T. Tully. 2017. Genetic variation in light vision and light-dependent movement behaviour in the eyeless Collembola Folsomia candida. Pedobiologia – Journal of Soil Ecology 61:33-41.
Applied conservation ecology
We are using our knowledge of population demography and evolutionary ecology to gather demographic and try to help managers implement appropriate conservation strategies. One such project included a demographic study of a small, threatened population of the Orsini’s viper (Vipera ursinii ursinii) monitored by Jean-Pierre Baron since 1979. Another was a geographic survey of abundance, genetic and phenotypic distribution of lizard species in the Seine & Marne department, for which we designed standardized sampling protocols.
Baron, J.-P., Le Galliard, J.-F., Ferrière, R. and T. Tully. 2012. Intermittent breeding and the dynamics of ressource allocation to growth, reproduction and survival. Functional Ecology 27(1):173-183.