Forexample, existed in geologists have established that mountains once gan, and portions of present-day Minnesota, Wisconsin, Michi- and Manitoba, Canada. Today, region consists oflow hills rock plains because erosion gradually destroyed these peaks The record contains evidence that shows Earth has experienced many cycles of mountain building and erosion. Concerning the ever-changingnature of Earth through great expanses of geologic time, Hutton made a that was to become his most famous. In concluding his classic 1788 paper published in the Transactions of the Royal Society of Edinburgh, he stated, "The results therefore, of our present enquiry is, that we find no vestige of beginning-no prospect of an end It is important to remember that although many features of our physical landscape may seem to be unchanging over our life times, they are nevertheless changing, but on time scales of hun dreds, thousands, or even many millions of years