Articles, books and book chapters

@article{https://doi.org/10.1111/1365-2656.13317,

title = {Micro-geographic shift between negligible and actuarial senescence in a wild snake},

author = {Thomas Tully and Jean-François Le Galliard and Jean-Pierre Baron},

url = {https://besjournals.onlinelibrary.wiley.com/doi/abs/10.1111/1365-2656.13317},

doi = {https://doi.org/10.1111/1365-2656.13317},

year  = {2020},

date = {2020-01-01},

journal = {Journal of Animal Ecology},

volume = {89},

number = {11},

pages = {2704-2716},

abstract = {Abstract While it has long been known that species have contrasted life expectancy (pace of mortality) and generation time (pace of reproduction), recent studies have also uncovered that the shape of adult age trajectories of mortality and reproduction can vary remarkably among species along a continuum of senescence ranging from strong deterioration (senescence), insignificant deterioration (negligible senescence) to improvement with advancing age (negative senescence). As for many long-lived ectotherms with asymptotic growth and increasing reproductive output with age, snakes are good candidates for negligible senescence to occur. Yet, intraspecific variation in the pace and shape of actuarial and reproductive senescence across wild populations of these species remains to be explored. Here, we used 37 years of mark–recapture data in two nearby habitats inside a meadow viper Vipera ursinii population to quantify life expectancies, generation times and the shape of actuarial and reproductive senescence. Female vipers maintained stable reproductive performances at old ages, even when accounting for the predicted increase of fertility with body size, providing evidence for negligible reproductive senescence in both habitats. Males had a higher adult mortality and a shorter life expectancy on average than females and actuarial senescence shifted from negligible senescence in the optimal habitat to strong senescence in the sub-optimal habitat. Overall, these results demonstrate that micro-geographic environmental variation can generate qualitative shifts in actuarial senescence patterns. This highlights that taking into account the within-species plasticity of age-dependent trajectories could prove useful in better understanding what determines the evolution of life-history age trajectories.},

keywords = {ageing, life-history trade-off, phenotypic plasticity, reproductive effort, survival},

pubstate = {published},

tppubtype = {article}

}

@article{bleu_reproductive_2013,

title = {Reproductive allocation strategies: a long-term study on proximate factors and temporal adjustments in a viviparous lizard},

author = {Joséfa Bleu and Jean-François Le Galliard and Patrick S Fitze and Sandrine Meylan and Jean Clobert and Manuel Massot},

url = {https://link.springer.com/article/10.1007/s00442-012-2401-1},

doi = {https://doi.org/10.1007/s00442-012-2401-1},

issn = {0029-8549},

year  = {2013},

date = {2013-01-01},

journal = {Oecologia},

volume = {171},

number = {1},

pages = {141--151},

abstract = {Optimisation of reproductive investment is crucial for Darwinian fitness, and detailed long-term studies are especially suited to unravel reproductive allocation strategies. Allocation strategies depend on the timing of resource acquisition, the timing of resource allocation, and trade-offs between different life-history traits. A distinction can be made between capital breeders that fuel reproduction with stored resources and income breeders that use recently acquired resources. In capital breeders, but not in income breeders, energy allocation may be decoupled from energy acquisition. Here, we tested the influence of extrinsic (weather conditions) and intrinsic (female characteristics) factors during energy storage, vitellogenesis and early gestation on reproductive investment, including litter mass, litter size, offspring mass and the litter size and offspring mass trade-off. We used data from a long-term study of the viviparous lizard, Lacerta (Zootoca) vivipara. In terms of extrinsic factors, rainfall during vitellogenesis was positively correlated with litter size and mass, but temperature did not affect reproductive investment. With respect to intrinsic factors, litter size and mass were positively correlated with current body size and postpartum body condition of the previous year, but negatively with parturition date of the previous year. Offspring mass was negatively correlated with litter size, and the strength of this trade-off decreased with the degree of individual variation in resource acquisition, which confirms theoretical predictions. The combined effects of past intrinsic factors and current weather conditions suggest that common lizards combine both recently acquired and stored resources to fuel reproduction. The effect of past energy store points out a trade-off between current and future reproduction.},

keywords = {cohort effects, energy stores, life history, phenotypic plasticity, reproduction, reproduction, size at birth, trade-off, trade-off, viviparity, Zootoca vivipara},

pubstate = {published},

tppubtype = {article}

}

@article{gonzalez-suarez_population_2011,

title = {Population and life-history consequences of within-cohort individual variation},

author = {Manuela González-Suárez and Jean-François Le Galliard and David Claessen},

url = {https://www.journals.uchicago.edu/doi/abs/10.1086/661906},

doi = {https://doi.org/10.1086/661906},

issn = {0003-0147},

year  = {2011},

date = {2011-01-01},

journal = {The American Naturalist},

volume = {178},

number = {4},

pages = {525--537},

abstract = {The consequences of within-cohort (i.e., among-individual) variation for population dynamics are poorly understood, in particular for the case where life history is density dependent. We develop a physiologically structured population model that incorporates individual variation among and within cohorts and allows us to explore the intertwined relationship between individual life history and population dynamics. Our model is parameterized for the lizard Zootoca vivipara and reproduces well the species' dynamics and life history. We explore two common mechanisms that generate within-cohort variation: variability in food intake and variability in birth date. Predicted population dynamics are inherently very stable and do not qualitatively change when either of these sources of individual variation is introduced. However, increased within-cohort variation in food intake leads to changes in morphology, with longer but skinnier individuals, even though mean food intake does not change. Morphological changes result from a seemingly universal nonlinear relationship between growth and resource availability but may become apparent only in environments with strongly fluctuating resources. Overall, our results highlight the importance of using a mechanistic framework to gain insights into how different sources of intraspecific variability translate into life-history and population-dynamic changes.},

keywords = {body size, demography, demography, density, metabolism, performance, phenotypic plasticity, phenotypic plasticity, size-structured populations, stochasticity, structured population models, Zootoca vivipara, Zootoca vivipara, Zootoca vivipara},

pubstate = {published},

tppubtype = {article}

}

@article{le_galliard_ontogenic_2006-1,

title = {Ontogenic sources of variation in sexual size dimorphism in a viviparous lizard},

author = {Jean-François Le Galliard and Manuel Massot and Meta M Landys and Sandrine Meylan and Jean Clobert},

year  = {2006},

date = {2006-01-01},

journal = {Journal of Evolutionary Biology},

volume = {19},

number = {3},

pages = {690--704},

keywords = {body size, maternal effect, phenotypic plasticity, sexual size dimorphism, viviparity, Zootoca vivipara},

pubstate = {published},

tppubtype = {article}

}