system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do flies seem to swarm and buzz around a dead animal rather than land and stay on it?

It seems like there are more flies in the a air than actually on the carcass.
gpt
This is a great question, one I'd never thought of before. 

Flies are competitive and fight for "landing rights" on a carcass. Those fights occur both on the dead animal and in the air above it, making a flying swarm over the corpse as they jockey for position.

Beetles that crawl up to the corpse, on the other hand, fight as they get closer and closer to it, making a higher concentration of beetles near the edge of the carcass, with fewer initially getting up on it and towards the center of the body.

Maggots, on the third hand, dig and use digestive juices to liquify the corpse. And fly eggs are laid in masses and hatch fairly simultaneously. So staying in large masses with other maggots makes eating easier, as digestive juices are shared among all.