"Extinct human being" is a really poor choice of words. Interesting article nonetheless.

My thoughts exactly! Extinct?

This individual is probably from a late migration (4,000-5,000ya).

I'll bet you a dollar the mtDNA Hg from this indivdual is D2. Siberian origin.

http://anthropology.uwaterloo.ca/ArcticArchStuff/astt_fig_migration.html

Unfortunately the Palaeoeskimo are extinct.  They arrived in the Eastern Arctic around 4500 years ago and vanished at more or less the same time that the ancestors of the Inuit moved in. They were a genetically distinct population and the current research and other DNA work on Palaeoeskimo remains confim that they had no input into the modern Inuit gene pool.  Culturally and biologically, they are extinct.  There was some really cool research published in 2005 that suggests that they may have contributed some genetic material to a distinct population called the Sadlermiut who were still making chipped stone tools up to their extinction in the winter of 1902-03 from introduced disease.

2005 Hayes et al. Molecular Archaeology of the Dorset, Thule, and Sadlermiut: Ancestor-Descendant Relationships in Eastern North Amercian Arctic Prehistory. in Contributions to the Study of the Dorset Palaeo-Eskimos.

Thanks for the link Trast.

Given that all known extant humans can breed with all other known extant humans, and given the assumption that all identified humans during the last 20,000 years are of the same general genetic stock, calling a group with some differential phenotypical expression, and cultural adaptations a distinct line of humans seems rather odd to me. It would seem to present a thin edge of a wedge if we then proceed to define every measurable difference in populations as notable distinctions, and then define those differences as qualifications for defining a separate line of human being, while withholding the ideas of standard speciation criteria. Should we say that the Nordic Greenlanders and Vinelanders are an extinct human line since their line does not extend much beyond their period of arrival? (Obviously a rhetorical question for we know they backtracked their way "home" when environmental conditions no longer favored their means of adaptation).

Does the book above discuss whether or not the lineage is found at its point of origin beyond the period where it is last seen in North America?

I suppose in the case of the Palaeoeskimos its a little like an isolated island population that seperates from their parent population, develops independantly and then vanishes.  Here in Newfoundland we had a gentically distinct population of wolves that were hunted into extinction.  Not all wolves are extinct, and the ancestral population of wolves isn't extinct, but the Newfoundland Wolf is.

The Palaeoeskimos spread into the High Arctic around 4500 years ago and developed a remarkably distinct material culture that persisted with a few changes until about 800 years ago.  Palaeoeskimo sites and artifacts dissapear and Thule Inuit sites show up in their place around that time.  Culturally, there don't appear to have been many ideas transfered between the groups and now from the genetic studies there doesn't appear to have been any transfer of genes either.  The Palaeoeskimos moved into a new area, developed a culture in situ for approximately 4000 years without any apparent influx of ideas or genes from the parent population or neighboring groups and then died out without passing on their culture or genes to any surviving descendants.  The parent population in Siberia still exists, but over the several thousand years separating the two groups there was genetic drift and when the Palaeoeskimo dissapeared they were a culturally and genetically unique population.  There doesn't appear to be anyone alive carrying genes from the Palaeoeskimo people who moved into the Western and Eastern Arctic.  They were a culturally and genetically distinct branch of human beings that completely and utterly stopped existing. 

"Extinct" sounds harsh and unlikely, but if anyone could do it, it would be the Palaeoeskimos.  They seem to have thrived on 'harsh and unlikely' and completely erasing themselves from our family tree seems like exactly the sort of thing they'd be able to pull off.

"...There doesn't appear to be anyone alive carrying genes from the Palaeoeskimo people who moved into the Western and Eastern Arctic.  They were a culturally and genetically distinct branch of human beings that completely and utterly stopped existing..."

What was the mtDNA Hg of  the subject "Palaeoeskimo"?

Is that mtDNA hg extinct (Hg D2)?

http://tech.groups.yahoo.com/group/HumanMigrations/message/4004

http://dienekes.blogspot.com/2008/05/mtdna-haplogroup-d2a1-in-paleo-eskimo.html

http://en.wikipedia.org/wiki/Haplogroup_D_%28mtDNA%29

"...The sample is distinct from modern Native Americans and Neo-Eskimos, falling within haplogroup D2a1, a group previously observed among modern Aleuts and Siberian Sireniki Yuit. This result suggests that the earliest migrants into the New World's northern extremes derived from populations in the Bering Sea area and were not directly related to Native Americans or the later Neo-Eskimos that replaced them..."

https://www.sciencemag.org/cgi/content/abstract/320/5884/1787

http://www.phylotree.org/tree/subtree_D.htm