Origins of Paleoindians

From Wikipedia, the free encyclopedia

This page covers the origins of Paleoindians. The Paleo Indians populated the North America at the end of the last ice age.

Contents 1 The Land Bridge 2 The Dyukhtai of Northeast Asia 3 Southeast Asians: Paleoindians of the Coast 4 The Paleo-Arctic 5 The Aleuts and Inuit 6 The Paleoindians 7 Paleoindian Genes 8 Bibliography

[edit] The Land Bridge

The Last Glacial Maximum (LGM) of the Wurm/Wisconsin glacial period occurred approximately 20,000-18,000 years ago. Extremely cold weather resulted in the formation of vast ice sheets across the northernmost areas of both continents. Glaciers also formed south of the 30th parallel in the Andean Mountains along the western coast of South America. As the ice sheets formed, sea levels dropped worldwide. When the Bering and Chukchi seas had dropped some 400 feet lower than their present level, land beneath the Bering Strait was exposed. This was the land bridge Beringia, an ancient Ice Age subcontinent that united the eastern and western hemispheres [1 140; 2 60].

The Bering land bridge was a treeless, grassy tundra over 1000 miles wide. Broad temperature fluctuations produced below-freezing nighttime conditions. Permafrost kept the soil frozen year round except in the summer when the first few inches of topsoil became waterlogged and spongy.

Several groups from Asia migrated across Beringia and were ultimately responsible for populating North America. One group of European big-game hunters travelled across Siberia to Beringia. Another group of Southeast Asians built and used boats to skip along the coastline of the Pacific Rim.

After 18,000, the world began to warm up and the ice sheets began to melt which caused the seas to rise. Massive flooding occurred from 15,000 to 13,000 when "ice dams" high in the mountains were breached. By 14,000 the land bridge lay submerged beneath the Bering Strait [3 199, 206; 4 1; 5].

[edit] The Dyukhtai of Northeast Asia

From 35,000-12,000, one group of northeast Asians had populated a region near Dyukhtai Cave on the Aldan River. The Dyukhtai may have been the first humans to enter the New World through the interior eventually spreading into Beringia and British Columbia [1 140]. Beringia may have been populated as early as 24,000 by bands of hunter-gatherers like the Dyukhtai who had migrated out of Asia in pursuit of Pleistocene mammals such as the giant beaver, goats, elk, ancient reindeer (early caribou), horses, Yukon camels, steppe bison, musk ox, mastodons, and woolly mammoths.

The chief characteristic of the Dyukhtai was their manufacture of microliths or microblades. Microblades are small flakes less than 1 1/4 inches long, with a sharp edge and a "backed" or blunted edge that could be guided with the index finger to sever meat from a carcass. Microblades could also be incorporated into composite tools such as an arrow or sickle. Thousands of microblades have been found at some upper Paleolithic Stone Age sites. They have been found north of Mongolia together with projectile points and hand-carved ivory statuettes. The earliest of several sites there has been dated 45,000. Microblades appeared in Japan by 20,000 during the LGM when the island was still a peninsula and reachable by land [1 144, 202; 3 189-191].

Microblade manufacture was a very important event in human history. The appearance of microblades roughly corresponds to the end of the Middle Paleolithic in 60,000. Over 98% of all human history is encompassed by the period of time that began with the appearance of Australopithecus afarensis [e.g. "Lucy"]--a maker and user of Oldowan chopper tools--and ended with the manufacture of microblades by lower-upper Stone Age cultures such as the Dyukhtai. Percentage-wise, the last 60,000 years of human history has been rather insignificant compared to the whole of human evolution that may have began in Africa 3.5 million years ago with A. afarensis.

[edit] Southeast Asians: Paleoindians of the Coast

The boat-builders from Southeast Asia may have been the first group to reach the shores of North America. One theory suggests men in boats followed the coastline from the Kurile Islands to Alaska to Chile [2 62; 7 54, 57]. The Haida nation on the Queen Charlotte Islands off the coast of British Columbia may have originated from these early Asian mariners between 25,000 and 12,000. The theory of "paleo-boats" would also explain the habitation of coastal sites in South America such as Pikimachay Cave in Peru by 20,000 and Monte Verde in Chile by 12,000 [6 30; 8 383].

"'There was boat use in Japan 20,000 years ago,' says Jon Erlandson, a University of Oregon anthropologist. 'The Kurile Islands (north of Japan) are like steppingstones to Beringia,' the then continuous land bridging the Bering Strait. Migrants, he said, could have then skirted the tidewater glaciers in Canada right on down the coast." [7 64]

[edit] The Paleo-Arctic

The manufacture of microliths and composite tools from 27,000-7,000 is known as the Northeast Asian-Northwest American Microblade Tradition (NAMANT) or the Paleo-Arctic tradition. This was the first stage in colonization of the Arctic and included both continents. The Paleo-Arctic tradition contained elements from both southeast Asian boat-building and northeast Asian microblade technologies.

The Paleo-Arctic tradition diffused into North America by 14,000 when the earliest inhabitants of the Aleutian Islands began to exploit the coast for fish and sea mammals. Paleo-Arctic (or Stage 1) sites include Anangula (>7,000) on Umnak Island in the Aleutian islands chain, Onion Portage (15,000), and Old Crow Flats (29,000) in the Yukon just east of the Alaskan border [6 34, 45-46].

Many languages and dialects were spoken on both sides of the Bering Strait around 14,000. The Asian Paleo-Arctic tradition would eventually give rise to the modern maritime hunting and gathering cultures of the Koryak, Tungas, Chukchee, and Siberian Inuit. The American Paleo-Arctic tradition appears to have diverged into at least two groups--the Aleuts and Inuit of the Arctic and the Paleoindians.

[edit] The Aleuts and Inuit

One group adapted to the rich resources that could be harvested from the sea. These Upper Stone Age hunters set microblades into grooves on bone points, hafted them onto various types of shafts, and used them to hunt seals, whales, and caribou [3 195-196; 6 34, 45-46]. They were probably the first people on earth to build watercraft by covering wooden frames with sealskins.

The Paleolithic ended by 10,000 and, in the New World, was followed by the Middle Lithic. By the end of the Middle Lithic in 7,000, small isolated settlements had appeared on the Aleutian Islands, the Alaskan Peninsula, and on both sides of the Seward Peninsula. After 4,500, continued melting of the polar ice cap opened the arctic waters and permitted widespread settlement along the Arctic ring from Alaska to Greenland. This culture of arctic dwellers would eventually become the Aleuts and Inuit--modern hunters and fishers of the Arctic [6 43-44, 46].

[edit] The Paleoindians

The Wisconsin ice sheet that covered Canada was almost 2 miles thick and blocked any movement through the interior by Paleo-Arctic dwellers. By 12,000, it had broken up into two smaller ice sheets--the Cordilleran and the Laurentide. This formed the McKenzie corridor--an ice-free passage from Alaska to the Montana-North Dakota border. Paleo-Arctic populations that remained on the Arctic coast were generally more adept at hunting sea mammals and fishing than those who pursued caribou, mammoths, and other terrestrial mammals into the interior once the McKenzie corridor opened [2 60, 62; 3 206].

"Paleoindians are thought to have lived primarily as small, mobile groups of big game hunters." [9 129]

Paleoindians travelled light and moved frequently--they were always moving to find new sources of plant foods and wild game. They did not carry much food and their tool kit of microblades was easily transported. Their diet was often sustaining and rich in protein due to successful hunting.

A highly mobile people such as the Paleoindians, probably had a surprisingly high reproductive rate. Travelling light during frequent moves was a more efficient utilization of calories than hunting and foraging further and further away from more permanent encampments. Paleoindians could carry more and provide for more children on the move than if they had built permanent settlements. In the bottleneck of Middle America, their birth rate decreased when "new" hunting grounds were found already populated by other bands. This slowed their progress and allowed the higher costs of more permanent residence to accumulate [10 501-504].

The Paleoindians may have moved every 3-4 days and covered 150 to 200 miles a year [10 501-502]. A thin population of humans spread over both Americas by 11,000 when the Clovis culture appeared in the Southwest. Paleoindians are generally associated with Clovis spearpoints that were hafted to darts and hurled from atlatls at the last mammoths on earth. Clovis culture was gone in 300 years but the stage had been set for the appearance of the earliest American Archaic Indians [3 205, 210].

[edit] Paleoindian Genes

The gene pool of Paleoindians (and today's Native Americans) may have arisen from that of the present-day Ainu. The Ainu are an ancient culture of hunters, gatherers, and farmers who still live on the Japanese island of Hokkaidō and the Kurile Islands in the archipelago north of Japan. A small population of Ainu still survive. They possess features of both Japanese and the European Caucasoid: light complexions, wavy hair, and sturdy bodies [7 54].

In addition to the Ainu, other present-day hunter-gatherer societies that have remained isolated in northeast Asia and North America and whose ancestors may have contributed to the gene pool of Paleoindian are the Yukaghir, Inuit, Aleut, Koniag, Kamchadal, Chukchi, and Koryak. However, in one anthropological study, only three groups of Gm allotypes (i.e. special blood proteins) were found in Native Americans. One group is supposedly that of the Paleoindians (which also includes thousands of Central and South American Indians) and the second is that of the Inuit and Aleuts. Another study involving mitochondrial DNA suggests a single founding tribe diverged into 4 specific mtDNA lineages responsible for 95% of all Amerindian genotypes. These 4 lineages may have roots in present-day Siberian, Mongolian, and Tibetan populations. A fifth lineage has been associated with European or Eurasian populations [3 204; 11 226-227; 10 56-58].

The most telling physical evidence for the ancestry of the first Americans is a unique "shovelling" of the two central upper incisors. The posterior surface of the teeth is hollowed like a shovel and referred to as sinodonty. Sinodonty is common amongst populations of Native Americans in North, Central, and South America; and in Turkestan (from the Caspian Sea to the Gobi Desert), Southeast Asia, the Pacific Islands, and Siberia. A population of Sami from Finland are also classified as sinodonts.

Opposed to sinodonty, sundadonty is found from Africa to Central Asia and Scandinavia. Except for some skulls found in Minnesota and dated about 8,500, all prehistoric North and South American fossils display a common Asian ancestry [3 196-198, 233, 236; 7 53, 55].

[edit] Bibliography

1. Gowlett, John. Ascent To Civilization. New York: Alfred A. Knopf, 1984.
2. Petit, Charles W. "Rediscovering America." U. S. News & World Report, October 12, 1998.
3. Fagan, Brian M. The Journey from Eden. London: Thames and Hudson, 1990.
4. Gilsen, Leland. "6) Paleo-Indian Period." May 29, 1999. Oregon Archaeology: Prehistory. June 2, 2000 <http://www.ncn.com/~gilsen/webdoc6.htm>.
5. Beringia Research. Yukon Beringia Interpretative Centre. Dec. 7, 2000 <http://www.beringia.com/02/02index.html>.
6. Coe, Michael, Dean Snow, and Elizabeth Benson. Atlas of Ancient America. New York: Facts On File Publications, 1986.
7. Begley. Sharon and Andrew Murr. "The First Americans." Newsweek, April 26, 1999.
8. Roosevelt, A. C. et al. "Paleoindian Cave Dwellers in the Amazon: The Peopling of the Americas." Science, April 19, 1996.
9. Price, Douglas and Gary Feinmen, editors. "Monte Verde Early Hunter-Gatherers in South America." Images of the Past. 1997.
10. Surovell, Todd A. "Early Paleoindian Women, Children, Mobility, and Fertility." American Antiquity, 65 (3), 2000.