Preliminary Analysis Offers More Details About 1000 Year Old Bones Discovered in McGrath

Nov 22, 2013

Fairbanks, AK - A construction project in McGrath last year uncovered three skeletons.  Authorities opened a missing persons case, but it turns out these remains have been “missing” for much longer than anyone expected.  Radiocarbon dating shows the bones could be a thousand years old.  Scientists have spent the last year analyzing DNA and isotopes to find out more about who the individuals were, what they ate and  whether they are related to people living in the McGrath area today.

It’s been a year since Tanana Chiefs Conference Senior Archaeologist Bob Sattler announced that remains of three people discovered in McGrath in 2012 are between 800 and 1000 years old.  “We have an opportunity for the first time, I think in Alaska, to look at three generations of the biological evidence or signatures in those individuals to determine possibly their migration patterns diet and so forth," he says. 

The remains, known as the ‘Tochak McGrath Discovery,’ are those of two adult men and a child. It’s not yet clear whether the child was male or female.  But scientists do know how old the individuals were when they died.  “The older adult guy is somewhere in the range of 35 to 40 years old," says Sattler.  "The younger man is somewhere in the range of 19 to 20 years old and the child is two to three years old.”

All three skeletons were found together buried by layers of ancient river sediment.  Geoff Hayes is a population geneticist at Northwestern University’s Feinberg School of Medicine in Chicago.  He’s analyzing DNA from the bones.  “You know the interior of Alaska is a really large area and we know next to nothing about the genetics of the people that lived there either now or in the past, so I think this is a really exciting start to try and pursue that and learn more about it,” says Hayes.

All humans inherit genetic information from both of their parents.  Hayes’ analysis shows the two older men share a patriline, meaning the genetic information they would have inherited from their father is the same. “But we don’t know how closely related they are," Hayes explains.  "They could easily be based off the data we have so far be distantly related cousins as they are father son or uncle nephew.”

Hayes says deeper genetic analysis is difficult because the remains are so old.  But there are other stories to be told.  Hayes is working with TCC as well as the tribal government in McGrath to find living relatives.  He may also be able to look at linkages between ancient and modern health and disease. “So, for example, we have a really good idea of the particular genetic markers that are associated with obesity and type two diabetes," he says.  "With the collaboration of other investigators who do the genetic of prehistoric populations, we could be looking for similarities and differences in the frequencies of particular genetic risk factors in the individuals that lived several hundred years ago and those that live in the region today.”

The remains also shed a little light on how people lived along the Kuskokwim River in the past.  Scientists have long believed ancient Alaska Native diets were rich in fish, but archaeologists rarely find fish bones at ancient campsites.  An isotopic analysis of the Tochak-McGrath remains shows the men relied heavily on fish as part of their diet.  Carrin Halffman is an Anthropologist at the University of Alaska, Fairbanks.  She was surprised to find that even the child was eating fish. “The child has a nitrogen isotope signal that suggests it had been weaned for a long time, at least a year," Halffman says.  "Now at first, it was two to three years old and that would be a rather late time for weaning, but in the past, people nursed children for a much longer time,” she says. 

A team was in McGrath this summer to excavate more of the site. TCC has a memorandum of understanding with the McGrath Native Village Council and MTNT, Limited a native Corporation that serves four villages in the region.  The research agreement is for five years.  When the studies are complete, the remains will be returned for a traditional reburial ceremony.