system
Given the following post, respond as if you're commenting on Reddit:
human
What do old insects die of?

If humans who die of old age generally die of heart failure or cancer, what do old insects die of? I know the mayfly is supposed to live for a day, and that some spiders can live for years- but what actually kills them?
gpt
Many species of mayflies, and other insects, don't eat as adults but only as larvae.  Once they become adults they have the brief life span to reproduce before dying from being unable to fuel their bodies/hunger.  A lot don't even have mouth parts once they become adults because their purpose at that point is only to reproduce.