The team collected over 130 of these Ecuadorian tree frogs by combing museum archives, searching the rainforest and raising some eggs in captivity, the study said. A pattern began to emerge.

Eungella whirring tree frogs live in upland rainforest at elevations of at least 2,800 feet, the study said. They are often found sitting on the ground near “slow-flowing” creeks and streams ...