“Behaviour is caused by people’s genes and biology, not the way they were raised.” Do you agree? Why?

Behavior, as well as intelligence, was hotly debated in the 20th century. Those who felt environmental influence was primary were known as environmentalist while those who felt inheritance held sway were known as hereditarian. Each had scandals serious enough - with fabricated research and non-existent assistants - to make the whole field irrelevant.

Charles Locurto wrote a book, Sense and Nonsense about IQ, in which he presented his theory that individual differences, separate from inheritance and environment, were the primary driver. Given the histories of heroes, and that Homo sapiens is the most individualistic animal known, it makes perfect sense.

When Abraham Maslow attempted to define a "hierarchy of needs" in 1943, he was being mocked by actual (but not yet reported) behavior two years earlier in Auschwitz (first source). When a person who devoutly wishes to live chooses to die in a very painful way for a stranger, are we to ascribe that behavior to genes or to upbringing? In the video below, in which a homeless man comes to the rescue of a stranger and gives his life in the process... again: genes or training (the ones that led him to the behaviors that caused him to be homeless)?

https://www.youtube.com/watch?v=TQg-tqbQ6CI

My nephew, who has never had any contact with his biological father, is eerily like him. He walks the same way, has the same mannerisms, and makes the same facial expressions. It's crazy how alike they are. I think genetics has a lot greater impact on behavior than we think.

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