Meeting Abstract
Theory predicts that natural selection will favor plasticity in spatially or temporally heterogeneous environments that vary in predictable ways. Like most traits, the potential for plasticity to evolve depends on the degree of heritability and strength of selection. To gain insight into evolution of plasticity, we assessed among-family variation in developmental plasticity for a variety of phenotypes in the brown anole (Anolis sagrei), and then evaluated the strength of selection on family-level reaction norms. Eggs from wild-caught females were incubated under thermal environments that mimicked temperature regimes characteristic of the early vs late reproductive season. Offspring were uniquely marked, measured for their size and locomotor performance, and then released onto an island near the collection site of their mothers. Recapture efforts were performed before and after the first winter to quantify offspring survival and natural selection on phenotypes, as well as on family-level developmental plasticity. Incubation duration was significantly shortened by late-season temperatures, and this pattern did not differ among family groups. For morphological and performance traits, however, late season thermal conditions generally produced larger and faster offspring than early season regimes, but the strength and direction of the effects varied substantially among family groups. This family-level variation in reaction norms suggest that plasticity observed here might have a genetic basis. In addition, this variation in reaction norms provides an opportunity for selection to operate on plasticity. Next, we will quantify the strength and form of selection on reaction norms to better understand how embryo responses to developmental environments are shaped by selection.
