Figure 1.

Developmental mechanisms use social and non-social cues to adapt organisms to their current and future conditions. These mechanisms have been shaped, across generations, by selection pressures that depend on temporal autocorrelation in the social and non-social environment. Within generations, developmental mechanisms are also exposed to temporal autocorrelation in the environment, which depends on social and non-social dynamics. Any adaptive evolutionary account of an early-life effect needs to specify each link in the argument and provide evidence that the assumed covariances actually exist in ancestrally relevant environments.