Maternal exposure to predator scents: offspring phenotypic adjustment and dispersal

Abstract

Predation is a strong selective pressure generating morphological, physiological and behavioural responses in organisms. As predation risk is often higher during juvenile stages, antipredator defences expressed early in life are paramount to survival. Maternal effects are an efficient pathway to produce such defences. We investigated whether maternal exposure to predator cues during gestation affected juvenile morphology, behaviour and dispersal in common lizards (Zootoca vivipara). We exposed 21 gravid females to saurophagous snake cues for one month while 21 females remained unexposed (i.e. control). We measured body size, preferred temperature and activity level for each neonate, and released them into semi-natural enclosures connected to corridors in order to measure dispersal. Offspring from exposed mothers grew longer tails, selected lower temperatures and dispersed thrice more than offspring from unexposed mothers. Because both tail autotomy and altered thermoregulatory behaviour are common antipredator tactics in lizards, these results suggest that mothers adjusted offspring phenotype to risky natal environments (tail length) or increased risk avoidance (dispersal). Although maternal effects can be passive consequences of maternal stress, our results strongly militate for them to be an adaptive antipredator response that may increase offspring survival prospects.

Parental effects enhance risk tolerance and performance in offspring

“…In contrast to our results, we note that previous work has found that parental experience with risk can increase offspring antipredator behavior under risk (Shine and Downes 1999, Storm and Lima 2010, Giesing et al 2011, Bestion et al 2014. However, unlike our study, offspring in these experiments were exposed to risk for very brief periods of time (,20 minutes).…”

Ecophysiological effects of predation risk; an integration across disciplines

“…Not only can predators shape prey growth responses to temperature, but predation risk may have complex impacts on behavioral thermoregulation within and across generations. A recent paper by Bestion et al (2014) shows that gravid female lizards exposed to snake predator cues give birth to offspring that thermoregulate differently, choosing cooler environments and reducing basking behavior. Collectively, these findings have strong implications for our general understanding of how climate warming will impact species interactions.…”

Effect of maternal predator exposure on the ability of stickleback offspring to generalize a learned colour–reward association

“…For example, in a diversity of taxa, mothers exposed to predation risk produce offspring with altered phenotypes compared to offspring of unexposed mothers (e.g. birds: Coslovsky & Richner, 2011; daphnia: Agrawal, Laforsch, & Tollrian, 1999; fish: McGhee, Pintor, Suhr, & Bell, 2012; mammals: Sheriff, Krebs, & Boonstra, 2009; insects: Storm & Lima, 2010; reptiles: Bestion, Teyssier, Aubret, Clobert, & Cote, 2014). There is growing appreciation of the ecological and evolutionary significance of such nongenetic transgenerational effects (reviewed in: Badyaev & Uller, 2009; Monaghan, 2008; Sheriff & Love, 2013).…”