system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are exoskeletons on small creatures and not large ones like elephants?

Thinking why I don't see ants the size of dogs or vice versa.
gpt
It has to do with breathing. Arthropods breath through spiricles or book lungs. They don't actually breath, air diffuses into these tubes. This limits their size. Structure function. Love that bio/zoo!