Chicks hatching from eggs is an innate behavior. Innate
behavioral adaptations are the result of millions of years of evolution. This
type of behavior is already "hard-wired" in the nervous system of
organisms and is usually inflexible. This is where a certain given stimulus triggers
the exact same response over particular organisms through time. The same adaptation
goes for other species that are naturally inclined to walk hours after their
birth, like giraffes and elephants do. It is in a way nature's natural
adaptation for species to survive through the course of time.
