An original objective of these multidisciplinary studies was to determine the position of the Aleuts in the Aleutian ecosystem with time depth. This has been done in a variety of ways. One of the most useful approaches is the construction of life expectancy tables. The greater longevity of Aleuts compared with Eskimos represents an effective biological and cultural human adaptation within this ecosystem. The Aleuts defined their ecosystem by expanding to the limits of the area they could effectively exploit with their complex technology, population structure, and population deployment system. Their intellectual achievements played a tangible role in their longevity in the pre-Russian period, and their sophisticated knowledge of human anatomy is both a causal and a consequential correlate of their longevity. From the Aleut point of view, the food resources were diverse, abundant, and accessible, and they also provided fabricational materials necessary for their complex material culture. The Aleuts successfully hunted the world's largest range of sea mammals, from the sea otter to the whales. At the same time, extensive use of invertebrates easily available on the ice-free strandflats enabled disadvantaged sectors of the population to make important contributions to their own food supply and thus improve life expectancy.

The rich food and fabricational materials antedate the Holocene history of Nikolski Bay and the arrival of the ancestral Aleuts. The natural resources of this area are fundamentally related to the former peninsular extension of Beringia and the permanent upwelling system in Samalga Pass. Sea otters, seals, and sea lions were present when the first Aleuts came to the area. Nikolski Bay has been an ideal place to obtain samples representing the entire Holocene Epoch. The earliest Asiatic migrants came from Siberia and traversed the southern coastline of Beringia. They established a large and permanent village on the northern arm of Nikolski Bay and remained there while expanding to the far ends of the Aleutian domain in the sixth millennium of their residence.

The record of cultural change spans a lithic revolution. It begins with a conservative unifacial core and blade industry that preserves several Asiatic traits but includes stone lamps, dishes, an image of the deity, and the use of red ochre. Between 7000 and 6000 years ago bifacially flaked and stemmed points appear, with some continuing elements of the old unifacial industry. This transition culture continues to about 4500 years ago, when the standard sequence seen in the old midden of Chaluka takes form. This culture continues, adding and subtracting various elements but always maintaining a distinctive configuration through time, to the present Aleuts, whose connection with the first Anangula settlement includes having remembered an older Aleut designation, "the place of the blades," and collecting eggs on its flanks.

The dating of events inside Nikolski Bay and the identification of the Asiatic elements do throw light on human migration from Siberia into Alaska. The Aleuts and Eskimos may well have been a part of a single population system of Bering Sea Mongoloids who expanded along the Siberian coasts and across the southern Beringian coasts. The population that reached Nikolski Bay became Aleuts. Those closer to the old mouth of the Kuskokwim River and further north became Eskimos. The rise of sea level presented no problems to marine-adapted people. Instead it presented more opportunities in the form of more coastline to exploit. The ancestors of the American Indians migrated earlier through the interior of Beringia.

The double-thumb hypothesis of …