Christian Science Monitor: If you were to cross a rabbit with a hamster, make it very sensitive to heat, and deposit it on mountains throughout the western United States, you`d be wasting your time because it looks as though somebody has already done it. The American pika, a small furry mammal in the same order as rabbits and hares, makes its home at high elevations where it enjoys the cold. Pikas that are exposed to temperatures over 80 degrees Fahrenheit tend to overheat and die. Which is exactly what …