We finish the first season by introducing the method by which we will explore human nature: Evolutionary Psychology.
Evolutionary psychology studies the human mind through the process of evolution — the mind is a collection of adaptations meant to solve recurrent problems of reproduction or survival encountered over evolutionary history.
This means that classically undesirable emotions like hate, aggression, and jealousy are not necessarily bad — they are solutions to problems. Those humans who could express hate, aggression, and jealousy under the right conditions out reproduced those humans who could not.
We discuss some of the criticisms and misunderstandings of evolutionary psychology. The first are just-say-so stories. Evolutionary Psychology is full of plausible explanations that are ultimately unfalsifiable. We address this criticism by demonstrating how to falsify a evolutionary hypothesis through incest avoidance.
Humans have inbuilt disgust responses against having sex with their siblings because reproducing with close relatives results in inbreeding depression. The incest avoidance hypothesis could be falsified by showing that there is a systematic absence of incest avoidance throughout human populations.
We then disgust the common misunderstanding of invoking a single counterexample as evidence that an evolutionary hypothesis is incorrect. If humans have innate incest avoidance how do we explain European royalty intermarrying in the 16th century?
This is a fundamental misunderstanding of what assertions an evolutionary hypothesis makes. Variants exist in populations of biological organisms — mechanisms can misfire, or be suppressed. Evolutionary hypothesis are population level claims not universal claims. A single counterexample is not sufficient to falsify a claim based on statistical averages.
We then address the everything is learned argument. The everything is learned arguments posits that behavior is not innate — but rather is learned. People are taught to avoid having sex with their sibling — they are taught how to behave — they are taught how to speak their language.
However, this explanation does not pass scientific scrutiny. Saying that everything is learned is no better than providing magic as an explanation. We must understand the specific physiological structures that allow humans to learn. Learning is an adaptation. We discuss the example of language to illustrate this point.
Finally we address two common misunderstandings: evolutionary psychology implies genetic determinism, and if its evolution we can’t change it.
Genetic determinism is the belief that genes determine our behavior regardless of environment. Evolutionary psychology does not support genetic determinism, it is an interactionist framework, all behavior requires environmental input. It is not a question of genes or environment, but genes and environment. Evolutionary psychology dissolves the nature vs nurture distinction as a false dichotomy.
By understanding what environmental input results in the activation of a behavior, we can avoid or promote conditions which promote the expression of a behavior. As an analogy we talk about the callous, an adaptation which hardens our skin in response to friction in the environment. Knowing what environmental input results in the formation of a callous allows us to avoid conditions which cause its growth.
