system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can small invertebrates, such as ants, survive long-distance falls that would kill most vertebrates?
gpt
Part of it is simply their weight. Terminal velocity for an ant is much lower than for a human. It won't hit the ground with as high speed as a human will.

Additionally, when it does hit the ground, it won't hit the ground with as much force because it's much lighter. The heavier something is, the greater structural integrity it requires to not collapse, however, that extra structural integrity adds even more weight, so there is a limit to how big things can be.

Because an ant is so light, it doesn't need heavy bones to keep itself from collapsing under its own weight, which further reduces how heavy it is.

A mouse will survive greater falls than a human too, relative to its size. An elephant, however, can't survive nearly as high a fall as a human, relative to its size.

Also, ants are soft, and they don't have bones that can break. Furthermore, ants don't have a vascular system, so they don't have any blood vessels that can rupture and cause internal bleeding. Most insects "breathe" through pores in their body, which directly enriches blood with oxygen. There's no need to circulate the blood through the entire body and eventually to a set of lungs. 

This is also what typically limits the size of insects. The oxygen concentration in the air. The greater the oxygen concentration, the bigger an organism that "breathes" like that can grow before "suffocating" itself. They were much bigger when there was more oxygen in the atmosphere.