Beyond “just-so stories”: How evolutionary theories led to predictions that non-evolution-minded researchers would never dream of

In The Origin of Species Darwin (1859) wrote, ‘In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation.’ However, critics of evolutionary psychology claim that the field consists entirely of ‘just-so stories’. Here, I discuss three examples of behaviours that may never have been investigated if they hadn't first been predicted by evolutionary theories.