Not a lot of detail in this story, but it's an interesting datum:
Head lice taken from 1,000-year-old mummies in Peru support the idea that the little creatures accompanied humans on their first migration out of Africa, 100,000 years ago, researchers reported on Wednesday.
Writing in the Journal of Infectious Diseases, Reed and colleagues noted that there are three known strains, or clades, of head lice -- A, B and C.
Clade A is found everywhere, clade B is common in both North America and Europe, and clade C is rare. There had been a theory that clade B evolved separately in the Americas and that European explorers carried A to the Americas and brought B back to Europe with them.
This is David Reed's work. The Peruvian mummy lice were all members of clade A, meaning that it had been in the Americas before the entry of Europeans.