It had been staring up at him all along. From the depths of the shower drain, as a matter of fact.

Hair. Strands of DNA calling cards. Abundant. Everywhere.

But it wasn't until a routine archaeological dig in search of clues to the identity of the first Americans that anthropology professor Dr. Robson Bonnichsen began to see hair for the buried treasure it truly is.

Hair offers the same genetic information as bones and teeth, previously the only human remains studied to define our ancestors. The importance, however, is not in the what to study but in the how much. "Having millions of little clues all around increases the chances and the rapidity of determining who the first Americans were," Bonnichsen says.

At the Center for the Study of the First Americans (CSFA) in Corvallis, Oregon, founded and directed by Bonnichsen, there's never a bad hair day. Volunteers painstakingly process bags upon bags of excavated sediment searching for strands that will provide the genetic recipe of the first humans to call the New World home.

And the odds are in the volunteers' favor.

"Hair is ubiquitous," Bonnichsen says, waving the statement about not so much as an explanation but as an exclamation of his work. Hairstylists estimate that humans lose an average of 100 hairs or hair fragments a day. During a sixty-year period, that's roughly 2.2 million strands of genetic proof that you (and your ancestors) once walked this earth.

Where to get hair, therefore, has never been a problem. Well preserved in such oxygen-sparse environments as dry caves and permafrost, hair is found at many known archaeological sites. The problem was how to get the hair from the excavation site to the laboratory without contaminating it.

Hair has been ignored by archaeologists for years because it becomes tainted the moment it is touched. Bonnichsen found the answer: wearing rubber gloves at the site and in the lab where the follicle is analyzed. CSFA jumped the final hurdle to successfully analyzing ancient tresses when it developed a flotation process that extracts hair from sediment.

While Bonnichsen isn't certain what his new-found methodology, dubbed molecular archaeology, will lead to, he is hopeful that learning about the past will benefit the present. Knowing just how ancient a genetic disease is, for example, may ultimately help scientists understand why some cultures are more prone to Alzheimer's or diabetes or alcoholism.

"Cultural and genetic evolution are coupled together," Bonnichsen says. "We want to find out what cultural practices led to certain genetic mutations."

So while few of us rejoice at its accumulation around our homes, we can all take comfort in knowing that hair, if nothing else, proves that we were. It is the mark of our existence. And the aged axiom will be confirmed in the statement, "I shed, therefore I am."

By Samantha Martin
Photo by Laura Goss