Genetics, prehistory and the colonisation of the Aleutian Islands

Abstract

The 1800 km-long Aleutian archipelago represents a model ecosystem to track human–environmental interactions across space and through time. Defining the southern margin of Beringia across which much of the early peopling of the Americas occurred, the Aleutians present a 9000 year record of human occupation in the eastern part of the island chain, and more than 3000 years in the west. Molecular evidence demonstrates: (1) that Aleuts shared common ancestry with Chukchi and Siberian Eskimos of Chukotka; (2) the original patterns of migration into the Aleutian islands were from the Alaskan peninsula in a westward direction with no evidence for island-hopping from Kamchatka; and (3) a highly significant statistical relationship between geography and genetics, based on mtDNA sequences, was observed despite previous population disruption. Historically, the Aleutian region is a rich ecotone, with ocean fisheries, abundant populations of large marine mammals, thick kelp forests, complex near-shore ecosystems and intertidal zones, spawning streams, and a highly diverse avian fauna. Each of these environments and resources has been pivotal in shaping the adaptive strategies of human occupants of the island chain since the initial colonisation of the Aleutians from the Alaskan Peninsula. In turn, Holocene human immigration, prehistoric cultural adaptations and subsequent historic events have had reciprocal impacts on the natural systems of the Aleutians.

Ornithogenic vegetation: How significant has the seabird influence been on the Aleutian Island vegetation during the Holocene?

“…Seabird activity as an important factor remains insufficiently studied. The Aleutian Islands are remarkable because there were predominantly no terrestrial predators east of the Commander Islands and west of Umnak prior to the start of their human colonization in 1741 (Crockford, 2012 ; Maron et al., 2006 ; West et al., 2007 ). Due to this, billions of birds have formed large colonies on the Aleutian Islands over thousands of years (Byrd, Day&, 1986 ; Crockford, 2012 ; Croll et al., 2005 ; Krylovich et al., 2019 ; Maron et al., 2006 ).…”

Refining the Paleo-Aleut to Neo-Aleut transition using a new ΔR for the eastern Aleutian Islands, Alaska

“…Archaeological and biological evidence currently suggests that Aleut ancestors crossed the exposed Bering Land Bridge to the Alaska Peninsula before turning westward and migrating across the Aleutian chain from east to west (West et al, 2007; Crawford and West, 2012). In the north Pacific, the Aleut dispersal was limited to available landfalls; the 1800-km-long Aleutian archipelago forms a curved line of more than 200 islands, divided into six island groups separated by turbulent ocean passes (Fig.…”

Geomorphic processes influence human settlement on two islands in the Islands of Four Mountains, Alaska

“…This channel avulsion may explain why Ulyagan is situated at a location that currently lacks a perennial water supply. Reworking of paraglacial fan sediments after the LIA may have produced the channel avulsion prior to the arrival of the Russians in 1759–1762 (Glotov’s voyage; Veniaminov, 1840) and the establishment of Russian era long-houses in Ulyagan village (West et al, 2007; Hatfield et al, 2016). If so, other factors must have promoted the continued use of a village site even as the water supply became less certain.…”

“…Thus, a reasonable expectation is that the IFM provided important intermediate waypoints between these larger island groups (Fig. 1A) during initial human colonization of the Aleutians in the early to mid-Holocene (e.g., West et al, 2007). Unexpectedly, the archaeological record of the IFM does not substantiate the direct physical presence of people until ~3.7 cal ka BP (Hatfield et al, 2016).…”