The paleo-climate of the Snake River Plain in southern Idaho, U.S., was much wetter and milder than today’s climate. During the Pliocene, the presence of a large lake provided habitat for fish. As the climate started to dry during the Pleistocene, vegetation similar to the present-day flora developed, although its geographical distribution was markedly different. Further drying occurred during the North American glaciation period that followed, resulting in the general aridity of the region today.
