Dick Orleans / PLOS ONE

Pikas are fluffy mammals that live at high altitudes across the West. They squeak when danger nears. The squeaky fluff-balls are considered indicators of climate change because they’re so sensitive to heat. Scientists say they have found some of animals in Colorado’s Rocky Mountains are behaving strangely.

Jessica Castillo Vardaro, a wildlife biologist with the University of California, Berkeley, studies pika genetics, a field that can involve some unusual data collection methods.