Understanding how early life effects evolve: progress, gaps, and future directions

Early life experiences have profound effects on later life health and on Darwinian fitness in many mammalian species, including humans. However, while it is clear that early life adversity often leads to compromised health, reproduction, and survival in adulthood, it is less clear why these links have evolved. Here, we review hypotheses from the evolutionary biology literature that have been proposed to explain how natural selection could...