Maternally chosen nest sites positively affect multiple components of offspring fitness in a lizard

Maternal nest-site choice is a behavioral phenotype with transgenerational consequences that can appear at multiple stages of offspring ontogeny. In many reptiles, the microenvironment surrounding eggs (e.g., moisture) can affect multiple aspects of offspring fitness across several life stages (e.g., embryo survival, phenotypic development, and posthatching survival). Thus, natural selection should favor maternal nesting behaviors that positively affect both embryonic and postembryonic ontogenetic trajectories. We tested this hypothesis in a 2-part laboratory experiment using the brown anole lizard (Anolis sagrei). In the first experiment, gravid lizards were given a choice of nesting substrates containing 5 levels of moisture content. By incubating eggs at the same 5 moisture levels, our second experiment tested if maternal choice of nest substrate facilitates embryonic development and enhances offspring quality and viability. Females strongly preferred nesting substrates with high moisture content, and these conditions yielded high hatching success, large offspring size, and overall increased offspring survival. These results suggest that selection has adaptively matched maternal nesting behaviors, embryonic development, and posthatching phenotypes in ways that enhance both offspring and parental fitness. In addition, our results highlight the importance of incorporating multiple life-history stages when assessing the fitness consequences of transgenerational effects.