How Much Do You Know About Your Brain?
The bio-chemical hardware in your head. You don't have to break down all these functions on a daily basis because it is automatic unless your brain is not working well, than it is more standard. For those who believe in the Ego and the Id the ego could be in the mid brain and the Id in the frontal lobe.
When we're fatigued or basic needs aren't met the potential for the horns coming out is there. We evolved to have higher functioning brains than apes because we can talk and type and more competent to get work done in the team setting. However, I don't think animals would ever make up "vengeance" that is a bad idea made by man. Every One Lives! ALL!