Today, three species of lice are known to us: body lice, hair lice and pubic lice.
Out of these three species, the body lice is the oldest, and it infested our primate ancestors around 25 million years ago.
Even when our ancestors split from the ancestors of chimpanzees around 7 million years, their hairy bodies continued to be home to body lice.
Then, about 4 million years later, our ancestors caught another type of lice that were found chiefly on gorillasHow they caught this type of lice of gorillas is still unknown.
Gradually, humans evolved to lose hair, and this “hairlessness” posed survival problems for these two species of lice.
Suddenly now, they didn’t have the forest of hair to deposit their eggs.
So, over the next one million years or so, these two species of lice evolved—the erstwhile body lice became head specialists while the gorilla lice became pubic lice.
Now, we had no body lice—just head lice and pubic lice.
Then another species of lice (the new body lice) emerged—known to be around 70,000 years old.
But like the old body lice, this new body lice couldn’t have survived on the hairless skin as their eggs would have fallen to the ground and died.
Experts believe that the new body lice could survive (and still exists) because they could deposit their eggs in human clothing.
And the evolution of this new body lice is considered evidence that we started wearing clothes around 70,000 years ago.
