It pertains to the surprising origins of the human pubic louse.
From the newscientist.com
It was expected that dating the split of the ancestral human louse into two species, the head louse and the pubic louse, would date the loss of body hair in human ancestors.
From the en.wikipedia.org
However, it turned out that the human pubic louse does not descend from the ancestral human louse, but from the gorilla louse, diverging 3.3 million years ago.