The ends of the geologic eras such as the Paleozoic and Mesozoic are marked by "climate changes" since these changes brought about devastating effects on the climate, which was crucial for the survival of many animals and plant life.
I believe the answer is <u>allusions</u>
Deforestation, overgrazing, and the overworking of soil for crop production can lead to Desertification.
He was a Southerner who supported California's admission as a free state.
