Estimation of the optimum density of the Selk'nam from Tierra del Fuego: Inferences about human dynamics in extreme environments.

The Selk'nam, a hunter-gatherer group that inhabited Isla Grande (Tierra del Fuego), became extinct soon after coming into contact with Europeans (XIX century). The population of this tribe was estimated from mission archives and the application of a hunter-gatherer ecological model. Both approaches suggest that the widely accepted number of 3,500-4,000 individuals for this human group is an overestimation, and that 1,500 may be more accurate.

Lack of founding Amerindian mitochondrial DNA lineages in extinct aborigines from Tierra del Fuego-Patagonia.

Ancient DNA from bones and teeth of 60 individuals from four extinct human populations from Tierra del Fuego-Patagonia (Selknam, Yamana, Kaweskar and Aonikenk) has been extracted and the mitochondrial DNA (mtDNA) amplified by using the polymerase chain reaction. High-resolution analysis of endonuclease restriction site variation in the mtDNA and sequencing of its hypervariable non-coding control region, revealed complete absence of two of the four primary mitochondrial haplotype groups present in contemporary Amerinds, namely A and B. In contrast, haplogroups C and D were found in all but one sample with frequencies of approximately 38% and 60%.

Dietary inferences through buccal microwear analysis of middle and upper Pleistocene human fossils.

Buccal microwear has been studied in a sample of 153 molar teeth from different modern hunter-gatherer, pastoralist, and agriculturalist groups, with different diets (Inuit, Fueguians, Bushmen, Australian aborigines, Andamanese, Indians from Vancouver, Veddahs, Tasmanians, Lapps, and Hindus), preserved at museum collections. Molds of an area of the buccal surface have been obtained and observed at 100x magnification in a scanning electron microscope (SEM). The length and orientation of each striation have been determined with a semiautomatic program of an image analyzer system (IBAS).

Intraindividual and intragroup variability of buccal tooth striation pattern.

Intrapopulational tooth striation variability has been studied in a sample of 99 individuals from the medieval agricultural population of La Olmeda (Palencia, Spain). The number, length, and orientation of all observed striations were recorded using a scanning electron microscope and an image analyzer system. Tooth striations were observed at 100x magnification on the buccal surface of Pm4 and M1 teeth.