Answer:
It dropped rapidly because the colonists were taking over more and more land and while doing that they were pushing them out of their land
1. Complete all your works
2. Study for your test
Native American tribes, including the Omaha, Oto, Missouri, Pawnee, Arapaho and Cheyenne, all ceded (gave up) land in Nebraska to the U.S. government. In all, there were 18 separate treaties between 1825 and 1892 in Nebraska alone. These treaties were a part of a much larger pattern of land transfers that allowed an explosion of European settlement. By 1850, the tribes had seen more people moving through along the Platte River. The Homestead Act, which gave free land to settlers, meant that large numbers of immigrants were now going to stay in the area. In this section, there are two major stories about Native Americans during the settlement period. First, there is the story of how native people met the challenges of living on this plains landscape. And second, there is the story of conflict as more and more people tried to live on the same land.
The answer is b. continental break-up. During this time, the continents began to
form and also separate in different areas. It was also the time of mammals as
dinosaurs were now extinct, mammals began to flourish in the earth. The climate
was now cooling down during this period.
