Buffalo

A buffalo losing his warm winter coat
Buffalo (more properly called bison) are a kind of cattle,
like cows. Like other cows, they came originally from Asia,
and they probably travelled over a land
bridge to get to North America. This was around
10,000 BC. The buffalo replaced an earlier
kind of bison, much bigger, which had become extinct, probably because of
climate changes, at the end of the last Ice Age. The big open grassy plains
of North America were just what buffalo liked, and soon there were millions
of buffalo in North America, anywhere that there was grass, from what is
now eastern Oregon all the way to the Great Lakes, and from Canada down
south nearly to Mexico.
Before 1500 AD, only a
few groups of people hunted buffalo much. It was too hard to chase them.
You had to chase them so that they would run off cliffs or get trapped in
valleys, and then you could kill them.
Once the Spanish invaders brought horses to North America, though, about 1600 AD, people were quick to see that this meant a great new source of food - with horses, men could hunt buffalo easily. Many tribes, like the Sioux, the Cheyenne, and the Ute, left their usual land, stopped farming, and migrated to the Great Plains to hunt the buffalo.
Once the Spanish invaders brought horses to North America, though, about 1600 AD, people were quick to see that this meant a great new source of food - with horses, men could hunt buffalo easily. Many tribes, like the Sioux, the Cheyenne, and the Ute, left their usual land, stopped farming, and migrated to the Great Plains to hunt the buffalo.

A herd of buffalo
This worked very well for several hundred years. But in the 1800's,
the railroad brought many Europeans to the West, and they saw the great herds of buffalo
for themselves. These Europeans wanted to conquer the West from the Sioux and the other
people who lived there, and they realized that if they killed all of the buffalo it
would make it much harder for people to live on the Great Plains.
A pile of buffalo skulls waiting to be made into fertilizer. Courtesy of the Burton Historical Collection, Detroit Public Library. © 1999
So the Europeans began to kill off all of the buffalo. They killed
them in huge heaps, not even taking the heads or the skins or the meat, just leaving them
there to rot. When people began to really kill the buffalo, their bodies
piled up across the Plains. By the 1880's only a few
hundred buffalo were left in North America.
Further reading on the Cherokee environment (click to go to Amazon.com's listing for this book):

Main environment page
Main North America page