Every organism on this planet is a product of evolution via natural selection. This fundamental, scientifically established fact is Herculean in its reach and power, in the sense that it’s capable of entering, unifying, and acting as a governing force for all of the different branches of science that deal with living things. Essentially, evolutionary theory is powerful and extensive enough to bring the whole shebang under its domain, including studies pertaining to human psychology and behavior.
Human behavior is not random
Human behavior is not arbitrary; rather, it’s been programmed over evolutionary time. This is not to say that we’re slaves to our instincts, forced to act in a specific way; however, there’s no doubt that our Darwinian selves greatly influence our actions and nudge us in a particular direction in life. This is something that’s readily apparent as one observes the conduct and demeanor of humans and helps us wrap out heads around the question of why we behave the way we do.
So as to illustrate this concept, I recently created an infographic that describes the evolutionary basis for some common human behaviors. The illustration is not exhaustive with respects to the behavioral causes it outlines; however, it does feature some of the principle evolutionary reasons for why we engage in the listed practices.