system
Given the following post, respond as if you're commenting on Reddit:
human
In spirit of Shark Week, why did Megalodon go extinct?

Couldn't they have survived by eating whales and other sharks?
gpt
Having an abundant food supply is no guaranty of species survival. There aren't any definitive answers as to why they went extinct because like most sharks the megalodon skeleton was made of cartilage and isn't preserved easily and doesn't fossilize. We only know of the megalodon because of it's teeth, which do fossilize, and bite marks in other creatures preserved bones.