system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why have sharks and alligators remain "unchanged" in hundreds of million of years, when humans have evolved immensely?

What prompts evolutionary stagnation? Is it an exaggeration to say they've remained unchanged?
gpt
There hasn't been drastic changes to their environment, whereas humans have seen major changes, and changes to their features have allowed them to fight ahead of the competition. If you think about it, there isn't much that would make a shark drastically better at catching fish.