Pubic hair provides evolutionary home for gorilla lice

Feb 11, 2009

There are two species of lice that infest humans: pubic lice, Pthirus pubis, and human head and body lice, Pediculus humanus. A new article in BioMed Central's open access Journal of Biology suggests one explanation for the separation of the two species.

In the article, Robert Weiss from University College London describes how he was struck by inspiration while pondering the question of why lice would separate into two groups when our ancestors are quite uniformly hairy, "I was having difficulty envisioning a clear separation of habitats between the groin and other parts of our ancient common ancestor. My 'eureka moment' came, appropriately enough, in the shower: although naked apes have pubic hair, surely our hairy cousins don't?"

Pthirus pubis, popularly known as crabs, evolved from the structurally similar gorilla louse, Pthirus gorillae. Interestingly however, while genetic analysis carried out by David Reed at the University of Florida indicates that this split occurred around 3.3 million years ago, humans are believed to have diverged from gorillas much earlier - at least 7 million years ago - suggesting that early humans somehow caught pubic lice from their gorilla cousins. Happily, this may not be as sordid as it sounds. According to Weiss, "Before one conjures up a King Kong scenario, it should be noted that predators can pick up parasites from their prey. The close contact involved in human ancestors butchering gorillas could have enabled Pthirus to jump hosts, rather as bushmeat slaughter practices allowed HIV to invade humans from chimpanzees in modern times."

So, while head lice may be viewed as a 'family heirloom', inherited down the generations as humans have evolved, pubic lice may well be a recent and slightly unwelcome gift from the more hirsute branch of our evolutionary family.

More information: Apes, lice and prehistory, Robin A Weiss, Journal of Biology 2009, 8:20 doi:10.1186/jbiol114, jbiol.com/content/8/2/20

Source: BioMed Central

Explore further: Italian olive tree disease stumps EU

add to favorites email to friend print save as pdf

Related Stories

Hitch-hiking with birds for life

May 14, 2012

Although chewing lice spend their entire lives as parasites on birds, it is difficult to predict patterns of lice distribution, new research from the University of Gothenburg, Sweden, reveals.

Lice genomes: Pieces of a new puzzle

Mar 30, 2009

Parents and school nurses take note. Lice are a familiar nuisance around the world and vectors of serious diseases, such as epidemic typhus, in developing regions. New research indicates that lice may actually ...

Recommended for you

Italian olive tree disease stumps EU

20 hours ago

EU member states are divided on how to stop the spread of a disease affecting olive trees in Italy that could result in around a million being cut down, officials said Friday.

China starts relocating endangered porpoises: Xinhua

Mar 27, 2015

Chinese authorities on Friday began relocating the country's rare finless porpoise population in a bid to revive a species threatened by pollution, overfishing and heavy traffic in their Yangtze River habitat, ...

A long-standing mystery in membrane traffic solved

Mar 27, 2015

In 2013, James E. Rothman, Randy W. Schekman, and Thomas C. Südhof won the Nobel Prize in Physiology or Medicine for their discoveries of molecular machineries for vesicle trafficking, a major transport ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.