system
Given the following post, respond as if you're commenting on Reddit:
human
What causes the physical changes in pigs when they become feral?

I understand when a pig becomes feral it changes physically; there’s an increase in size, longer coarser hair grows, and tusks develop.  What determines if other animals could have these changes?  Could a comparable transformation happen to humans?
gpt
Age. most domesticated pigs that you see are only yearlings, or occasionally 3-5 years old, if being used for breeding purposes. People don't usually let pigs get older than that because they get tougher to manage and more dangerous. Ferral pigs though, can live about 20 years. Also, domestic pigs have had their tusks removed, if they not going to be killed in the fall. It takes about 6 months before the tusks show up.