Most animals don't realise that they exist. But that doesn't mean they don't have an ego. Do only humans have an ego or can animals also be egotistical?

All organisms are programmed for their own survival, as well as the survival of their species. What distinguishes humans from animals is the ability to override programming through conscious thought. While animals feed themselves first, humans can consciously give way to another. Animals are primarily concerned with their own welfare and have no moral inhibitions.

What most animals do not have is the ability to perceive and recognise themselves. They do not have an ego consciousness, but they do have an ego.