system
Given the following post, respond as if you're commenting on Reddit:
human
How are mating phenomenon, particularly sexual cannibalism, evolutionary beneficial to a species?
gpt
If it increases reproductive fitness, it's evolutionarily beneficial.  Sexual cannibalism = nutrition for the mother = able to bear lots of young.

Evolution isn't about an individual's survival, it's all about who reproduces (and that those progeny themselves reproduce.)  

Males of species like preying mantises who let themselves get eaten had more kids than those who didn't.