Merriam’s Kangaroo Rat - This pair takes the heat in stride. In the southwestern U.S. and Mexico, kangaroo rats are already well adapted to arid conditions, and they’ve stayed robust during previous temperature hikes. The rodents are quick and flexible reproducers, and their diet of diverse seeds and occasional insects gives them wiggle room if some plant and bug species fizzle in the heat. FORT WORTH ZOO, TEXAS