Humans are blessed with two kinds of lice-- head and body lice, and pubic lice aka 'the crabs', . Pthirus has a weird evolutionary history which makes the scientists feel uncomfortable knowing it. From their research, homo sapiens acquired crab lice from gorillas 3.3 million years ago. The DNA structure of the human crab louse, andgorilla crab louse, were almost identical and shared a common ancestor. And we all know that crab louse is commonly acquired from sexual contact and able to live at the thick curly hairs in our private area.

However, scientists did not state that our ancestors had sex with the big apes. It would be more disgusting than the lemon party if they did. Scientists think that humans acquired it from sleeping in gorilla nests maybe because they were lazy to build a house on their own or scavenge the remains of these kings of the jungle. In fact, we can get crab lice from a shared bath towel.

This fact is indeed really weird, it is like finding out that the cute girl you admired so much in school and sometimes sexually fantasized is your cousin.