system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do animals sometimes kill themselves?

Is it because they know they are in a lot of pain or in a specific situation where it is better to terminate their life?

I've read online numerous accounts of animals committing suicide. I've personally witnessed a bunny kill itself after I accidentally bumped into it walking backwards while cutting the grass (it flopped violently for about a minute or two).

Are they aware of death? Is it done by conscious or a chemical reaction/signaling/programming?
gpt
I don't know about animals in general but domestic rabbits have been bred to have strong legs because that's where the good meat is.  If spooked suddenly, their legs are actually strong enough to snap their backs as they try to hop away.

I wouldn't call this suicide, I'd call it an effect of poor selective breeding.