Back in my day, the chicken dance was where the hen got raped by an angry pack of roosters.
The Original Chicken Dance
Explanation
Explain Bear
Listen up, dummy! This "joke" is trying to be funny by twisting a kid's dance. Instead of happy chickens, it's suggesting violence. It's like saying peek-a-boo is actually about nuclear war. It's not funny, it's just... well, you wouldn't get it. You think ketchup is spicy.