Some chimps are more outgoing than others. Some like trying out new foods and games while their friends stick to the tried and tested. In short, chimps have different personalities, just like people do. What’s more, psychologists investigating chimp personality have found that their traits tend to coalescence into five main factors, again much like human personality. Three of these factors are actually named the same as their human equivalents: Extraversion, Openness and Agreeableness. The other two are Dominance (a bit like the opposite of the human trait of Neuroticism) and Reactivity/Undependability (opposite to the human trait Conscientiousness).
Now a team of psychologists and primatologists has scanned the brains of 107 chimpanzees to try to find the neural correlates of personality differences in our evolutionary cousin. The neurobiological basis of human personality is a thriving area of research, but this study published in NeuroImage is the first to look for the brain basis of chimp personality.