Water restriction causes an intergenerational trade‐off and delayed mother–offspring conflict in a viviparous lizard

Abstract

Parenting is costly and because the relationship between the mother and embryos is not mutualistic, mother–offspring conflicts may exist whenever resource are scarce. However, intergenerational trade‐offs and conflicts resulting from limited access to water, a vital and depreciable resource, remain largely overlooked. In this study, we examined the physiological, reproductive and life‐history responses to water restriction in the European Common Lizard (Zootoca vivipara). We hypothesized that, under water‐limited conditions, pregnant females experience both short‐term and long‐term physiological impacts (dehydration and stress) underlying an allocation trade‐off for water between mothers and offspring. Water restriction led to a decrease in body mass, and an increase in plasma osmolality (dehydration) and corticosterone concentration in both males and females. The extent of the dehydration was positively correlated with fecundity in females. This suggests a trade‐off between maternal water balance and allocation of water to developing embryos during reproduction. Water restriction had no immediate effect on reproductive output or offspring morphology at birth. Yet, water restriction in pregnant females enhanced their reproductive effort the following year but reduced the early life growth and annual survival of their second‐year offspring. These delayed fitness responses to water restriction in offspring and mothers suggest that water can trigger intergenerational conflicts as demonstrated for energy. Although the mediation of this conflict remains to be clarified, we hypothesized that it represents a selective force that influences reproductive strategies. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.13009/suppinfo is available for this article.

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

“…identified with a unique toe clip code and maintained in conditions as previously described (Dupoué et al, 2018). identified with a unique toe clip code and maintained in conditions as previously described (Dupoué et al, 2018).…”

“…Maternal effort during gestation is thus mainly oriented to hormone or salt exchange with embryos, regulation of water supply, and thermoregulation (Dupoué et al, 2018;Le Galliard, Bris, & Clobert, 2003;Lourdais, Lorioux, Dupoué, Wright, & DeNardo, 2015). Maternal effort during gestation is thus mainly oriented to hormone or salt exchange with embryos, regulation of water supply, and thermoregulation (Dupoué et al, 2018;Le Galliard, Bris, & Clobert, 2003;Lourdais, Lorioux, Dupoué, Wright, & DeNardo, 2015).…”

“…Furthermore, reptiles are known to express considerable developmental plasticity in response to water conditions during embryogenesis (Packard, 1991). Maternal control of water allocation into offspring through hydroregulation mechanisms during gestation influences offspring fitness and can differentially influence sons and daughters (Dupoué et al, 2018;Le Galliard, Massot, Landys, Meylan, & Clobert, 2006). Maternal control of water allocation into offspring through hydroregulation mechanisms during gestation influences offspring fitness and can differentially influence sons and daughters (Dupoué et al, 2018;Le Galliard, Massot, Landys, Meylan, & Clobert, 2006).…”

“…Since water restriction protocol has previously been shown to significantly dehydrate females without modifying reproductive investment (Dupoué et al, , 2018, unbalanced sex ratios could imply WSD. We further investigated whether distorted secondary sex ratios could be explained by alternative hypotheses to WSD per se including (a) differential sex-biased mortality, (b) methodological biases, or (c) statistical artifacts.…”

Water restriction induces behavioral fight but impairs thermoregulation in a dry‐skinned ectotherm

“…In previous studies, we have shown that common lizards exposed to dry soil conditions invest more in exploration behaviors (Rozen‐Rechels et al ), and juvenile lizards living in dry habitats disperse more from their natal home range (Massot et al ), whereas sub‐adults reduce their locomotor activity during a chronic water restriction (Lorenzon et al ). Here, we repeatedly measured daily patterns of individual activity and microhabitat selection as well as body temperature and thermoregulation accuracy during one week in adult individuals, gravid females and males, exposed to a chronic water restriction (Dupoué et al ) compared to individuals having access to water ad libitum. To quantify potential interactions between water deprivation and heat stress, we implemented a mid‐day heat stress every two days.…”