The streams at Great Sand Dunes National Park may be key to preserving the Rio Grande cutthroat trout in the age of climate change, while restoration ecologists work to preserve other species and lands. Also, athletes are getting bigger and stronger. But is that a good thing? Then, humans have tried to kill coyotes going back more than 100 years. In Denver in the 1920s, a plant manufactured poison to exterminate them. But coyotes survived, and even multiplied and spread, while other animals in the same situation did not.