What Does Evolution Teach Us About Psychology?

Posted June 2019 by Clifton Stamp, B.S. Psychology; M.A. Rehabilitation Counseling, M.A. English; 10 updates since. Reading time: 5 min. Reading level: Grade 11+. Questions on evolutionary psychology? Email Toni at: editor@online-psychology-degrees.org.

Evolutionary psychology is an approach to psychology that uses the principles of Darwinian natural selection to describe and explain the origins of useful (adaptive) cognitive and psychological traits.  Arising from a confluence between cognitive psychology and evolutionary biology, evolutionary psychology looks at how biological evolution has shaped patterns of human behavior and the cognitive system we call the mind. To that end, psychology is seen as a function of evolutionary biology in which developments in the human brain and mind have been advantageous to the survival of the human species.

The Six Principles of Evolutionary Psychology

It’s necessary to understand that all evolutionary processes are blind. Evolution has no plans and no intentions. Rather, the environment of each organism works on them when situations arise that cause selection events. Selection events challenge organisms to adapt or die out, to survive or perish.  Remember, evolution doesn’t “aim” for anything. If an organism survives, it is because it demonstrated useful methods for surviving selection events. Behaviors that increase the likelihood of survival are adaptive. For complex organisms like humans, encountering the same problems over and over and resolving them successfully means that early humans equipped with a “problem-solving brain” lived long enough to pass on its genes.

For humans, those problem-solving skills include a highly efficient pattern recognition system, the ability to infer others’ emotions, establish kin and non-kin groups (useful in preventing incest), get along in social hierarchies, and generate novel behavior in the presence of new selection events.

The only true measure of survival mechanisms is the rate of success by which they enable their genes to be passed down from generation to generation. Remember, evolution isn’t a sentient process. It doesn’t consciously aim for anything, any more than weather aims to produce hurricanes or droughts, even though we anthropomorphize these processes. Human psychology is the result of millions of years of our brains solving problems that relate to survival, so behaviors that don’t appear adaptive today must have been, at least in one past epoch, useful.

That said, there are six principles of evolutionary psychology that are salient to our discussion:

  • The function of the human brain is to sort and process information by responding to stimuli that are both internal and external. The human brain’s purpose is to process information, and in doing so, it produces responses that are both reactive and proactive. Adaptive responses increase the likelihood of a human surviving long enough to pass on his or her genes and ensure the survival of his or her offspring. The brain is thus our prime survival tool.
  • The human brain developed by adaptation caused by natural selection. In essence, the human brain has continuously developed as a survival tool over generations.
  • The problem-solving centers of the brain developed over evolutionary time–hundreds of thousands of years.
  • Human problem-solving systems in the brain were shaped by problems and conditions that repeated over and over for many hundreds of thousands of years.
  • Mental processing is done largely unconsciously. Problems that might seem simple still require sophisticated neural processes.
  • The human brain is composed of many highly specialized mechanisms and processes that all together form human nature. Examples include language learning, food-gathering, predator avoidance and all social functions.

Evolutionary psychology’s primary hypothesis is that all the myriad psychological mechanisms of human cognition have a genetic basis and have thus been formed by natural selection.  Navigating conflict is a major part of human evolution. Some conflict arises from competition for scarce resources; mate selection is also another point of conflict. Reciprocity, extended social groups, and parenting are also areas that have been affected by natural selection.

An important concept in evolutionary psychology is the Environment of Evolutionary Adaptedness. The EEA refers to the whole set of environmental pressures that were common to humanity during our distant evolutionary history. Essentially, EEA refers not just a place, but the complete time and place that presented early humans with the most challenges and the most commonly occurring selection events.

We know that evolution continually shapes a species by exposing individuals to situations that result in life-or-death outcomes. Individuals that survive these selection situations live to pass on their genes. Over thousands of generations, adaptive human behaviors have led to success in passing on these same tendencies to act and react. Although highly specific behaviors aren’t encoded one hundred percent identically in the neurological circuitry of the brain, the general tendencies toward specific behaviors are indeed present in the neural pathways of each human brain.

Some theorists are critical of evolutionary psychology, pointing out that human behavior is extremely complex and susceptible to many external factors. However, evolutionary psychologists also note that tendencies to behave in flexible ways are more useful for human beings than hard-coded reflexes, as flexibility and the possibility of discovering adaptive novel behaviors is valuable in preventing organisms from becoming locked in to evolutionary dead-ends.

One problem with an evolutionary approach to psychology is that humans demonstrate behaviors that are no longer adaptive, but still persist. Behaviors that were once valuable tools for survival may no longer be adaptive, and in fact, can be detrimental to survival. The persistence of vestigial behaviors is just one of several areas for future research.

Evolutionary psychology teaches us that human behavior is affected by our neurological systems that in turn have been shaped by long evolutionary epochs. This selection-event driven shaping is far from over, as evolution continues to act on us.