GAINESVILLE, Fla. --- Humans acquired pubic lice from gorillas several million years ago, but this seemingly seedy connection does not mean that monkey business went on with the great apes, a new University of Florida study finds.
Rather than close encounters of the intimate kind, humans most likely got the gorilla's lice from sleeping in their nests or eating the giant apes, said David Reed, assistant curator of mammals at the Florida Museum of Natural History on the UF campus, one of the study's authors. The research is published in the current edition of the BMC Biology journal.
"It certainly wouldn't have to be what many people are going to immediately assume it might have been, and that is sexual intercourse occurring between humans and gorillas," he said. "Instead of something sordid, it could easily have stemmed from an activity that was considerably more tame."
About 3.3 million years ago, lice found on gorillas began to infest humans, Reed said. That they took up residence in the pubic region may have coincided with humans' loss of hair on the rest of their bodies and the lack of any other suitable niche, he said.
Reed and his co-workers' research stemmed from their fascination with humans' unique position among primates in being host to two different kinds of lice: one on the head and body (Pediculus), which has become the bane of many schoolchildren, and pubic or crab lice (Pthirus). In contrast, chimps have only head lice and gorillas pubic lice.
Understanding the history of lice is important because the tiny insects give clues about the lifestyles of early hominids and evolution of modern humans, Reed said. Because the human fossil record is patchy and finding early DNA samples is extremely difficult, parasites such as head lice, pubic lice, tapeworms and pinworms that have existed for millions of years provide valuable clues, he said.