Some mating behaviors also are species specfic. Prairie chickens, native to the upper Midwest, conduct an elaborate mating ritual, a sort of line dance for birds, with spread wings and synchronized group movements. Some behaviors are so characteristic that biologists use them to help differentiate between closely related species. Behaviors often breed true, that is, we can reproduce them in successive generations of organisms. Consider the instinctive retrieval behavior of a yellow Labrador or the herding posture of a border collie.
Behaviors change in response to alterations in biological structures or processes.
In humans, some behaviors run in families. For example, there is a clear familial aggregation of mental illness. Behavior has an evolutionary history, as demonstrated by the persistence of some behaviors across related species. Chimpanzees are our closest relatives, separated from us by a mere 2 percent difference in DNA sequence. We and they share behaviors that are characteristic of highly social primates, including nurturing, cooperation, altruism, and even some facial expressions.