Climate Effects on Growth, Body Condition, and Survival Depend on the Genetic Characteristics of the Population

Abstract

Climatic change is expected to affect individual life histories and population dynamics, potentially increasing vulnerability to extinction. The importance of genetic diversity has been highlighted for adaptation and population persistence. However, whether responses of life-history traits to a given environmental condition depend on the genetic characteristics of a population remains elusive. Here we tested this hypothesis in the lizard Zootoca vivipara by simultaneously manipulating habitat humidity, a major climatic predictor of Zootoca's distribution, and adult male color morph frequency, a trait with genome-wide linkage. Interactive effects of humidity and morph frequency had immediate effects on growth and body condition of juveniles and yearlings, as well as on adult survival, and delayed effects on offspring size. In yearlings, higher humidity led to larger female body size and lower humidity led to higher male compared to female survival. In juveniles and yearlings, some treatment effects were compensated over time. The results show that individual responses to environmental conditions depend on the population's color morph frequency, age class, and sex and that these affect intra- and inter-age class competition. Moreover, humidity affected the competitive environment rather than imposing trait-based selection on specific color morphs. This indicates that species' responses to changing environments (e.g., to climate change) are highly complex and difficult to accurately reconstruct and predict without information on the genetic characteristics and demographic structure of populations.

Some like it dry: Water restriction overrides heterogametic sex determination in two reptiles

“…Eventually, these variation in growth rates were paralleled by annual variation of the survival rate although the negative impact of year and maternal dehydration on survival was similar between males and females. Together, these annual and sex-specific responses are consistent with previous observations that male fitness curves are more sensitive to maternal dehydration and availability of free water in natural (Le Galliard et al, 2006) and seminatural or laboratory experiments (Dupoué et al, 2018;Romero-Diaz, Breedveld, & Fitze, 2017). These findings however stand against conclusions of theoretical evolutionary models of ESD and sex reversal, where growth and survival of sons from water restricted females should be higher than those of daughters (Charnov & Bull, 1977;Pezaro et al, 2017;Warner & Shine, 2008).…”

Climate suggests environment‐dependent selection on lizard colour morphs

“…physiological) relationship between climate variation and morph‐dependent survival (Friedman et al., ). In fact, our results may be explained by the environmental dependence of relevant population parameters, such as demography or sex‐ratio (Donald, ; Le Galliard, Fitze, Ferrière, & Clobert, ; Romero‐Díaz, Breedveld, & Fitze, ; Wapstra et al., ), which in turn affect the intensity of social selection (Le Galliard et al., ; Pérez i de Lanuza et al., ; Wapstra et al., ). Even sexual selection can be environment‐dependent (Roulin & Bize, ).…”

Age-dependent effects of moderate differences in environmental predictability forecasted by climate change, experimental evidence from a short-lived lizard (Zootoca vivipara)

“…While a recent review suggests that the effect of environmental variance may depend on mean environmental conditions 10 , no evidence exists that the effects of environmental predictability depends on mean environmental conditions. Moreover, environmental predictability may differentially affect the stages of stage-structured populations 11,12 , through its effect on inter-stage competition 13 , or due to inter-stage differences in the sensitivity to environmental predictability 14 . Therefore, differences may exist in population dynamics, but not necessarily in overall population densities 13 .…”

“…To this end, we experimentally tested in age-structured populations whether and how differences in precipitation predictability affect life-history strategies and life history traits of different age-classes (adults, yearlings, juveniles) of the European common lizard ( Zootoca vivipara ; Lichtenstein, 1823). Zootoca vivipara exhibits high dependency on water 22–24 and water availability constrains its life history traits, e.g., its growth and reproduction 11,25 . Its hydric balance is mainly controlled by environmental factors and behavioural regulation 23 .…”

“…Here, we experimentally manipulated the predictability of precipitation in 12 semi-natural European common lizard populations, while holding the amount of precipitation constant. The predictability of precipitation was manipulated, given the observed and predicted changes in rainfall patterns 18 and given the European common lizard’s high dependency on water 11,22–24 . Populations were maintained during one year and the experiment repeated in three subsequent years, to test for the generality of the responses and whether differences in mean climatic conditions may affect differences induced by precipitation predictability.…”