Do animals have ego?
No.
I don’t have it, and I don’t see a difference between me, a deer, a cat, or a squirrel. Two legs, two hands, two eyes - same thing. They all are basically just slightly different versions of me, variations. I am smarter, they are faster. I see no difference.
I don’t see a significant difference between killing a person and killing a mouse. It would be pretty much the same thing for me. Both acts are utterly insane and utterly inhumane unless I have a very serious, life-threatening problem with either of them. I can only have such problem with the mouse if it threatens my survival by eating my only food and killing it is the only option, and I can only have such problem with the human if he wants to kill me, maim me or otherwise seriously harm me. Otherwise it always makes more sense to cooperate. Isn’t it funny that if one wants to kill a mouse for revenge, we think he’s kinda coo-coo, but if one wants to kill a human for revenge, this is considered to some extent understandable. Go figure. I don’t understand what revenge is for, and I’m pretty sure that neither does the mouse.
So yes, there is no difference between me and other animals, none that I can see.
I do, however, see a significant difference between me and the vast majority of people. The smaller their egos, the less difference I see. When it comes to hairless monkeys that have been called enlightened masters and gurus, I only see a slight difference or no difference at all. None of that has anything to do with the amount or the quality of the spiritual words they use - this is not how I see.
The more they are proud of their “humanity” and elevate themselves above animals as higher evolved beings, the more difference I see. The more complex they are, and the more complex their psychology is, the more difference I see. Ego is basically human vanity, that’s what it is. It’s a uniquely human trait.
When I see a woman walking her dog, I see two beings indistinguishable from me. When I play with the dog, I see no difference. When I “play” with the human by conversing with her, if our conversation is light and mundane, I see no difference. But if it becomes deep and we start talking about values, morality, philosophy, religion, or spirituality then it becomes immediately clear to me that on some level she thinks she’s God and she suffers for it. I understand her and I sympathize with her, because I used to live the same way for some 40 odd years. The only way out of her current situation is through surrendering to her own pain and living through it, and who am I to press her buttons? Even if I do, she will probably just think I’m just a bad person and stay away from me, so I don’t. Her dog has no pain that I can see. Maybe a little bit from being conditioned to live in dependence and captivity, but it’s subtle. Wild animals have no pain whatsoever, they are ultimately free.
So, no, come to think of it, I don’t believe animals have egos.