system
Given the following post, respond as if you're commenting on Reddit:
human
Of animals that mate for life, does infidelity occur? What happens if one of the pair catch the other in the act?

I know that different pair-bonding species probably have varying levels of fidelity to their partners. I guess I'm wondering if we've ever seen a nasty albatross break-up or Sandhill crane divorce precipitated by some less-than-faithful bird.
gpt
Actually infidelity is quite prevelant in the animal kingdom although maybe it doesn't meet with the same rules as human infidelity, ie: they don't usually have long ongoing affairs, but animals do cheat on occasion if they can get access to better genetics. 

I've learned this in several biology course. In some species when females have access to a male that they think (due to cues) has a very good genetic makeup, they will copulate with that male when their longtime male partner is not around. If they are caught, the original male tries to drive off or kill the cheater male (called the cuckold male)