Maternal body condition influences magnitude of anti-predator response in offspring

Abstract

Organisms exhibit plasticity in response to their environment, but there is large variation even within populations in the expression and magnitude of response. Maternal influence alters offspring survival through size advantages in growth and development. However, the relationship between maternal influence and variation in plasticity in response to predation risk is unknown. We hypothesized that variation in the magnitude of plastic responses between families is at least partly due to maternal provisioning and examined the relationship between maternal condition, egg provisioning and magnitude of plastic response to perceived predation risk (by dragonfly larvae: Aeshna spp.) in northern leopard frogs (Lithobates pipiens). Females in better body condition tended to lay more (clutch size) larger (egg diameter) eggs. Tadpoles responded to predation risk by increasing relative tail depth (morphology) and decreasing activity (behaviour). We found a positive relationship between morphological effect size and maternal condition, but no relationship between behavioural effect size and maternal condition. These novel findings suggest that limitations imposed by maternal condition can constrain phenotypic variation, ultimately influencing the capacity of populations to respond to environmental change.

Maternally induced intraclutch cannibalism: an adaptive response to predation risk?

“…Fox & Czesak 2000;Hendry et al 2001) and has longterm effects on their growth and fitness (Roff 1992). Recent studies have suggested that maternal provisioning impacts plasticity in offspring defences and predator avoidance behaviours (Michimae et al 2009;Bennett & Murray 2014). For example, in the northern leopard frog (Lithobates pipiens), mothers in better body condition, who produced larger eggs, had tadpoles that developed greater morphological responses to predation risk (Bennett & Murray 2014).…”

“…Recent studies have suggested that maternal provisioning impacts plasticity in offspring defences and predator avoidance behaviours (Michimae et al 2009;Bennett & Murray 2014). For example, in the northern leopard frog (Lithobates pipiens), mothers in better body condition, who produced larger eggs, had tadpoles that developed greater morphological responses to predation risk (Bennett & Murray 2014). Importantly, in most taxa, the extent of maternal investment is adjusted plastically, as an adaptive response to local environmental conditions (e.g.…”

A suite of essential biodiversity variables for detecting critical biodiversity change

“…Individuals can also respond by not breeding or by reducing their energy expenditure through reduced offspring numbers, offspring size and parental care, which leads to reduced offspring survival (Mousseau & Fox, 1998;Karell et al, 2008;Rode et al, 2010;Johnson et al, 2014). Maternal condition can also influence offspring survival through the transfer of maternal hormones, antibodies or other substances (Karell et al, 2008;Bennett & Murray, 2014;Bergman et al, 2014) and therefore shows carry-over effects to future generations (Van Allen et al, 2010). However, individuals sometimes increase their reproductive effort as a terminal investment to maintain their breeding output, but may die of exhaustion after reproduction is complete (Clutton-Brock, 1984).…”

Genetic variation in parental effects contribute to the evolutionary potential of prey responses to predation risk

“…Specifically, we first estimate the contributions of maternal effects (V M ), relative to that of additive genetic (V A ) and environmental effects (V E ), for larval responses to predation risk. Second, we test if larval responses to predation risk –which are known to depend on the larva’s initial size–, are influenced by variation in maternal or paternal body size, a key trait known to impact offspring phenotype in many systems (Fox 1994; Bernardo 1996 a ; Fox and Czesak 2000; Bennett and Murray 2014). Finally, we estimate the relative contribution of additive genetic and environmental variances (V A and V E ) of maternal responses to predation risk, including changes in intraclutch cannibalism –a mechanism linked to an anticipatory maternal effect.…”