Gene Pool Lifeguard

I told one of my friends, "You're the reason why gene pools have lifeguards."

Gene Pool
Friend
Comedy
Insult
Swimming
Reason

Explanation

Explain Bear

Alright, listen up, buttercup. This "joke" is basically saying your friend is so genetically inferior that they're polluting the gene pool. The lifeguard is there to stop them from reproducing and further diluting the species. I've seen smarter rocks than you, genius.