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The Great Warming
The first human inhabitants of the Americas-the ancestors of today's Indians-came to the New World from northeastern Asia many thousands of years ago. The story of their coming is closely tied to events that took place at the end of the last great Ice Age.
At the height of the glacial period, or Pleistocene epoch, northern North America was covered by a very thick layer of ice. In the east, the ice cap extended as far south as Pennsylvania and seaward to the edge of the continental shelf. The area that is now Maine lay beneath ice more than a mile thick. Much of the world's water was tied up in the glaciers, and this lowered global sea levels, causing the shallow bottom of the Bering Strait between Alaska and Siberia to emerge from the sea and form a land bridge between the continents. At its maximum, this bridge was more than 1,500 kilometers wide and provided a natural route for both animals and humans to expand their ranges into the New World.
Beringia-the name given to the vast region made up of northeastern Siberia, the land bridge and Alaska during the Pleistocene-remained largely unglaciated because there was too little precipitation in the region for glaciers to form. However, during the coldest periods of the Pleistocene, when the land bridge was at itsmost extensive, access from Alaska to the south may have been blocked by the expansion and coalescence of continental glaciers in western Canada. The arrival of humans in the Americas would therefore have depended on the condition of the land bridge, the development of cultural adaptations that would have allowed people to survive in the harsh environment of Beringia, and the existence of ice-free routes south from Alaska.
The Pleistocene lasted almost two million years, ending about ten thousand years ago. During that period the glaciers waxed and waned a number of times, providing numerous opportunities for people to enter the Americas. For years there has been a spirited debate within the archaeological community over the timing of human arrival in the New World. Some evidence from a few archaeological sites suggests that people may have been in the Americas by thirty thousand to twenty thousand years ago, and perhaps considerably earlier. However, none of the evidence for such an early arrival is entirely convincing, and the question of when humans first came to the New World remains open.
Around 18,000 B.P. the final major retreat of the glaciers began, heralding the end of the Pleistocene. By eleven thousand years ago, rising waters of the Bering Strait submerged the land connection between Siberia and Alaska, and retreating continental glaciers made routes south from Alaska accessible. This final glacial retreat seems to have opened up the Americas to a new human population: there is a sudden and unprecedented explosion of archaeological evidence dating to between twelve thousand and ten thousand years ago-our first firm evidence for human presence. Hundreds of archaeological sites dating to this period have been found all over the Americas, most of them characterized by a very distinctive stone-tool technology that varies little from region to region. It is from this period that we have the first evidence for human presence in Maine.
The Deglaciation of Maine
At its late Pleistocene peak, about 21,000 B.P., the continental glacier entirely covered Maine and the Gulf of Maine, reaching out to the edge of the continental shelf at George's Bank. At that time, sea level was about 100 meters lower than at present. Glacial retreat started around 18,000 B.P., and by between 15,000 and 14,000 B.P. the ice had receded to approximately the present coastline of Maine. The great weight of the glacier had depressed the land surface, so that as the ice continued to recede, the sea followed, flooding the lowered land and extending as much as 100 kilometers inland from the present coastline (Fig. 1-1). Fine sediment settling on the seabed created the Presumpscot formation, a clay deposit that covers the coastal lowland areas of Maine below about 120 meters elevation and extends up the Penobscot River Valley as far as East Millinocket and up the Kennebec as far as Bingham. Remains of vertebrate and invertebrate animals from the clay, including walrus (Odobenus rosmarus), bearded seal (Erignathus barbatus), and cold-water species of shellfish (e.g., Chlamys islandicus, Hiatella arctica, Portlandia arctica, Mya truncata, Mytilus edulis, Serripes groenlandicus) suggest that marine environmental conditions at the time were similar to those that prevail off the southern Labrador coast today.
This marine transgression was relatively short-lived, because as the land was relieved of the weight of the glacier, it began an isostatic rebound upward. The first land form to emerge was George's Bank, which enclosed the waters of the marine transgression, forming a nearly inland body of water called the Degeer Sea. By around 12,000-11,000 the sea had retreated back to the position of the present coastline, and by 10,000-9000 B.P. relative sea level was approximately 60 meters lower and the shore up to 20 kilometers further seaward than it is now. Thereafter, a continually rising sea level caused by the melting of glacial and polar ice gradually overtook the slowing isostatic land rebound, and relative sea level began to rise once again, a process that continues today.
By 11,000 B.P. the glacier had retreated to north of the St. Lawrence Valley, and Maine was essentially ice-free, although remnant ice masses may have persisted for a few centuries longer in northern Maine. Indeed, the next millennium saw a brief reversal of the warming trend, with a return to colder, drier conditions during what is called the Younger Dryas event. The extent and impact of the Younger Dryas in Maine is unclear, although its timing, during a critical period of plant, animal, and human colonization of the region, suggests that it played an important role.
As the land emerged from its burden of ice and water, colonizing plants spread a carpet of life over the raw landscape. The initial immigrants were mosses, lichens, grasses, and sedges-tundra vegetation suited to the cold and to the poor soils of the periglacial land. Later, thickets of willow and alder appeared, followed by stands of the hardier tree species such as poplar (Populus) and spruce (Betula).
An observer in Maine eleven thousand years ago would have seen a mosaic environment of tundra, shrubs, and trees arranged in patterns determined by latitude, elevation, local soil conditions, drainage, and exposure. Much of northern Maine and the higher elevations of western Maine was still covered by tundra vegetation. A mixed forest of poplar, spruce, pine (Pinus), birch (Betula), elm (Ulmus), larch (Larix), ironwood (Carpinus or Ostrya), fir (Abies), and oak (Quercus) had penetrated into southern Maine. In central and eastern Maine there was a broad band of woodland-an intermediate condition between tundra and a closed-canopy forest, with a mixture of stands of trees and open areas of tundra-composed primarily of poplar, spruce, and birch.
Although Maine's late Pleistocene woodland and tundra environments generally resembled modern subarctic tiaga (near treeline) or arctic tundra zones, they were probably biologically richer. In all likelihood, Maine, like the rest of the Northeast, supported a large and varied population of late Pleistocene animal species, including mammoth (Mammuthus primigenius and jeffersonii), mastodon (Mammut americanum), horse (Equus), muskox (Ovibos), bison (Bison), and caribou (Rangifer). And where these animals wandered, humans-their most dangerous and efficient predators-followed.
Hairy It-The Scarborough Mammoth
In 1959 James and William Littlejohn and Leonard Cash were digging a farm pond in the town of Scarborough when they came upon an elephant tusk preserved in a waterlogged clay deposit about 2 meters down (Fig. 1-2). Their find generated considerable interest, and several scientists visited the site, including geologist D. W. Caldwell of Wellesley College, who recovered three additional rib fragments and examined the geologic context of the find.
After the initial flurry of excitement no further work was done at the site until 1990, when museum personnel, led by natural history curator Gary Hoyle, began an intensive investigation of the remains. Mammoth expert Daniel Fisher of the University of Michigan examined the tusk and determined that it was from a young adult female mammoth.
Excerpted from Twelve Thousand Years by Bruce J. Bourque Copyright © 2001 by University of Nebraska Press. Excerpted by permission.
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|Introduction : the prehistoric past||1|
|I||The Paleo-Indian period||13|
|II||The Archaic Period||37|
|III||The Ceramic Period||75|
|IV||An introduction to the historic past||103|
|V||Early European and native contacts||111|
|VI||The second half of the seventeenth century||129|
|VII||The war years||147|
|VIII||The era of the mission||171|
|Epilogue : land, politics, and survival to the present||209|
|App||The traditional material culture of the native peoples of Maine||249|