Integrating social learning, social networks, and non-parental transgenerational plasticity.

Transgenerational plasticity (TGP) has largely focused on how parental exposure to ecological conditions shapes the phenotypes of future generations. However, organisms acquire information about their ecological environment via social learning, which can also shape TGP in profound ways. We demonstrate that non-parents alter how parents detect and respond to environmental cues in ways that spillover to affect offspring, non-parents influence offspring even without direct physical interactions, and parental cues received by offspring can alter the phenotypes of other juveniles. Because parents can draw on the experiences of a network of non-parents, these socially acquired cues may increase parents' ability to accurately detect environmental shifts and may explain why TGP is surprisingly ubiquitous despite theory predicting that it should be relatively rare.