See Chapter 5 of “IB Psychology: A Student’s Guide” for more information.
This topic requires you to explain one evolutionary theory of a specific behaviour. One behaviour we look at in my course is sexual attraction because humans have evolved to find certain characteristics of the opposite gender attractive. The characteristics or traits, that are attractive, are those that will provide the healthiest off spring with the greatest likelihood of survival.
Evolution is based on Darwin’s theory of the ‘survival of the fittest.’ What this basically means in a biological sense is that the organisms that are the most successful at procreating and reproducing will survive. Therefore, humans have evolved to find traits attractive that will have the greatest chance of carrying forward their genetic material. Put simply, we want to have healthy babies so our genes are passed on, and so we need to find a parter to procreate with that will provide us with the healthiest babies possible.
This has resulted in males and females (generally speaking) having an attraction to specific traits.
READ MORE: This post has a list of interesting videos and resources.