system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do flying insects spend such a large % of their life flying around? Doesn't it expend a lot of energy?

With birds, they seem to only fly if it's really necessary. Why are insects different?
gpt
Bugs actually don't have to expend hardly any energy at all to keep themselves flying.

They are so incredibly light that it takes very little energy to keep them in the air. It also takes very little energy to fuel them because food is plentiful if you're an insect and you can just fly around, access it, and you're so tiny it doesn't take very much.

Plus because most insects are willing and can eat foods other, larger creatures can't, just makes them even more adapted to survive.

Insects are pretty much the most successful group of animal life there is because of their small size.

One rotting meatball has enough calories to keep a fly alive for decades.

Whereas a bird is much, much larger, and can't be sustained as easily, thus energy conservation is something to consider.

With an insect they don't really have to worry about energy conservation because they live in a world of resources.