Page 9 - Reading Success B9

The height of the Ice Age was between 34,000 and 30,000 B.C. During this time a
significant portion of the world's water supply was contained in large continental
ice sheets . This caused the Bering Sea to be hundreds of meters below its current
level, which exposed a land bridge, known as Beringia, between Asia and North
America. At its largest, Beringia is thought to have been about 1,500 kilometers wide.
It was a moist and treeless tundra, that was covered with grasses and plant life. This
plant life attracted the large animals that early humans hunted for survival.

The first people to cross the land bridge into North America most likely did so
without knowing they had entered a new continent. They traveled along the Siberian
coast and then across the land bridge into what is now Alaska. Once in Alaska, it took
these early North Americans thousands of years more to move south through the
openings in great glaciers to what is now the United States. There is a large amount
of evidence of early life in North America. However, none of it can be reliably dated
before 12,000 B.C; a recently discovered hunting lookout in northern Alaska, is
thought to date from around that time. So too are some of the finely crafted spear
points and other items found near Clovis, New Mexico. These and similar artifacts
found throughout both North and South America indicate that life was well established
in a majority of the Western Hemisphere prior to 10,000 B.C.
This is around the time that the mammoth began to die out and be replaced by the
bison as the early North American’s principal food and hide source. As time passed
more and more species of large animals died out by either overhunting or natural
causes. This caused plants, berries and seeds to become an increasingly important
part of the early American diet. Eventually, foraging and the first attempts at
agriculture emerged. Indians that lived in what is now central Mexico led the way in
agriculture, cultivating corn, squash and beans, as early as 8,000 B.C. Slowly, this
knowledge spread northward.

By 3,000 B.C., primitive corn was grown in the river valleys of what is now New
Mexico and Arizona. Then the first signs of irrigation began to appear, and by 300
B.C., signs of early village life. In the early A.D. centuries, a tribe called the Hohokum
was living in settlements near what is now Phoenix, Arizona. There they built ball
courts and pyramid-like mounds reminiscent of those found in Mexico. They also
built canal and irrigation systems.

Main Idea

What is the main idea of this story?

a. the early peoples of the world
b. the development of early civilizations

c. the early peoples of the North American continent
d. life during the ice age

12_Reading Success B 9