system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are anal muscles involved whenever one sneezes ?
gpt
Hahahaha there's no delicate way to put this. It's to prevent you from forcefully shitting yourself. Humans evolved over time with certain traits that are suited for social groups. Groups that just pooped where they ate and lived died off. Somewhere along the line we developed a trait to clench up when we sneeze, that provided an advantage, that group bred more successful offspring, and eventually the trait became prominent in the species.