Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Y Chromosome Study sheds light on Athapaskan Migration to Southwest U.S.

16.07.2008
A large-scale genetic study of native North Americans offers new insights into the migration of a small group of Athapaskan natives from their subarctic home in northwest North America to the southwestern United States. The migration, which left no known archaeological trace, is believed to have occurred about 500 years ago.

The study, led by researchers at the University of Illinois, is detailed this month in the American Journal of Physical Anthropology. It relied on a genetic analysis of the Y chromosome and so offers a window on the unique ancestral history of the male Athapaskan migrants. Previous genetic studies of this group focused on mitochondrial DNA, which is passed down exclusively from mothers to their offspring.

The new findings reinforce the hypothesis that the Athapaskan migration involved a relatively small group that nonetheless was very successful at assimilating and intermixing with native groups already living in the southwest. The newcomers were so influential that the Athapaskan language family now dominates many parts of the Southwest. Now called Apacheans, the Navajo and Apache descendants of the early migrants are dispersed throughout the central Southwest and speak languages closely related to the Chipewyan, an Athapaskan language found in the subarctic.

(Language studies also revealed that Athapaskans migrated to the northwest U.S. and settled on the coast in parts of California and Oregon.)

How the Athapaskan migrants were able to spread their language – and genes – so successfully is unknown. Anthropologists note that the migrants probably arrived in the Southwest at a time of stress among indigenous groups as a result of an extended drought.

The new study also revealed how pervasively European males intermixed with native groups, said principal investigator Ripan Malhi, a molecular anthropologist in the department of anthropology at Illinois.

“A lot of the Y chromosomes have been replaced by European males,” he said.

Malhi and his colleagues looked at specific regions on the Y chromosome that can vary from person to person. Tiny differences in the sequence of nucleotides that spell out the genetic code can be used to determine whether – and how closely – individuals are related to one another. Those who share many of these genetic signatures are more likely to share a recent common ancestor than those who don’t.

The researchers analyzed 724 Y chromosomes from 26 native populations in North America. By including groups from across the continent (they studied tribes from Alaska to the Yucatan Peninsula and eastward to Hudson Bay and southeast U.S.), the researchers were able to analyze genetic differences among many native groups and to get an idea of the degree of European male infiltration into the native gene pool.

Consistent with a previous study of native North American mitochondrial DNA (also led by Malhi), the new analysis found a pattern that indicates that a small group of subarctic Athapaskans migrated to the Southwest. This pattern is reflected in the fact that many Apacheans carry the genetic signature of a small subset of subarctic Athapaskans.

These findings also affirm an earlier study of variants of a particular protein, albumin, in different native groups. That study showed that while many Apacheans carried an albumin variant common among natives in the Southwest and Mesoamerica, some Apacheans were the only ones to carry a variant that also occurs in subarctic populations.

Other patterns emerged from the Y chromosome analysis. One genetic signature associated with European males was detected in native males throughout North America, but was found at the highest frequency in groups living nearest to Hudson Bay, where trade between Europeans and the region’s indigenous peoples was established in the early 17th century.

The new study, along with the earlier genetic and protein studies and the language analyses, is filling a gap in the archaeological record of Athapaskan migration, Malhi said.

This gap is the result of the fact that the Athapaskan migrants seem not to have altered the physical landscape, architecture or cultural practices of the populations they assimilated in the southwest U.S.

The only lasting evidence of the Athapaskan migration found so far is in their language and their genes, Malhi said.

“We’re fitting together different lines of evidence,” he said. “We’re not just using the genetic data. We’re using it in combination with the linguistic, oral histories from elders in the community and archaeological data. And even though there has been over a century of archaeological research done in the Southwest, there’s not much information there about the Athapaskan migration into the Southwest.”

The team also included researchers from the Universidad Nacional Autonoma de Mexico, the University of California at Davis, Washington State University, the University of Montana, the University of Arizona and Trace Genetics.

Diana Yates | University of Illinois
Further information:
http://www.illinois.edu
http://www.news.uiuc.edu/news/08/0715athapaskans.html

More articles from Studies and Analyses:

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making Waves

Computer scientists use wave packet theory to develop realistic, detailed water wave simulations in real time. Their results will be presented at this year’s SIGGRAPH conference.

Think about the last time you were at a lake, river, or the ocean. Remember the ripples of the water, the waves crashing against the rocks, the wake following...

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Nanostructures taste the rainbow

29.06.2017 | Physics and Astronomy

New technique unveils 'matrix' inside tissues and tumors

29.06.2017 | Life Sciences

Cystic fibrosis alters the structure of mucus in airways

29.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>