How effective are maternal effects at having effects?

Abstract

The well studied trade-off between offspring size and offspring number assumes that offspring fitness increases with increasing per-offspring investment. Where mothers differ genetically or exhibit plastic variation in reproductive effort, there can be variation in per capita investment in offspring, and via this trade-off, variation in fecundity. Variation in per capita investment will affect juvenile performance directly-a classical maternal effect-while variation in fecundity will also affect offspring performance by altering the offsprings' competitive environment. The importance of this trade-off, while a focus of evolutionary research, is not often considered in discussions about population dynamics. Here, we use a factorial experiment to determine what proportion of variation in offspring performance can be ascribed to maternal effects and what proportion to the competitive environment linked to the size-number trade-off. Our results suggest that classical maternal effects are significant, but that in our system, the competitive environment, which is linked to maternal environments by fecundity, can be a far more substantial influence.

The influence of context-dependent maternal effects on population dynamics: an experimental test

“…From a population dynamic perspective, context-dependent and dynamic maternal effects are particularly important because the very life-history traits that are affected (e.g. survival, offspring size and number), can themselves determine the subsequent environment that mothers experience and respond to (Park 1935;Beckerman et al 2005;Benton et al 2005;Plaistow et al 2007). Thus, complex maternal effects will lead to complex patterns in the dynamics, feeding, in turn, into complex patterns of phenotypic dynamics.…”

The contribution of individual and maternal experience in shaping Daphnia life history

“…In our experiment, the life history parameters of individuals did not depend on their size at birth. In other words, differences in size at birth did not explain differences in other phenotypic traits expressed in later stages of ontogenesis, thus they were not the mechanism through which maternal effect operated, though they have been indicated as crucial path of maternal influence in earlier studies (e.g., Lampert, 1993;Tollrian, 1995;Beckerman et al, 2006). Mothers, therefore, had a more subtle impact on the development of their offspring via molecular or epigenetic transfer.…”

Maternal effects mechanism of population cycling: a formidable competitor to the traditional predator–prey view

“…The maternal transmission of individual quality can involve the endowment at birth of energy (proteins or lipids; Plaistow et al 2006), nutrients (Giron & Casas 2003), antibodies (Martinez-Padilla 2006), hormones (Grooothius et al 2005), parasites (Demastes et al 2003), etc. or the modification of offspring early environment through the schedule of provisioning of the offspring and their competitive environment (Beckerman et al 2006). All these features of individual quality reflecting the mothers' environment can affect the growth trajectory and demographic performance of their offspring.…”

“…Fox & Savalli 1998;Hercus & Hoffmann 2000) and their expression can be contingent depending on specific environmental circumstances (e.g. Räsänen et al 2005;Beckerman et al 2006;Plaistow et al 2006). Good theories, including these more complex scenarios, would require further theoretical developments.…”

“…For instance, maternal effects can modulate the investment of mothers through the trade-off between offspring size and number (e.g. Beckerman et al 2002Beckerman et al , 2006, they can last more than one generation (e.g. Fox & Savalli 1998;Hercus & Hoffmann 2000) and their expression can be contingent depending on specific environmental circumstances (e.g.…”