Question

What causes aggression in animals?

Answer 1

Deterioration of neural pathways in humans can also lead to aggression, in particular as we age.

Explanation:

I have read about how the Pre-frontal cortex in the human brain acts as a gate keeper to impulses, like anger, fear, that arise from the amygdala. Normally, these impulses are controlled and don't manifest themselves under normal conditions. But with aging, the connections between the pre-frontal cortex and the amygdala can become weakened. Consequently, some times older people can be prone to blurt out some angry comments or doing inappropriate things because this neural pathway is weakened. Hence the term "grouchy old curmudgeon"!!