The eastern grey tree frog (sound) looks exactly like the closely related Cope’s grey tree frog (sound). The big difference between the two species is beneath the surface—the eastern has twice the ...

"Errrrrrrrrt, errrrrrrrt" reverberated loudly from a small red maple tree along Brodhead Creek, just south of East Stroudsburg. This sound seems quite similar to the song of the very common ...

A Green frog (Rana clamitans) peers out from a pond in Arrowsic, Maine. There are nine species of frogs in the state and this common frog lives in Maine ponds, breeds in the summer, and hibernates ...

Every other Friday, the Outside/In team here at NHPR answers listener questions about the natural world. Today's question comes from Andy, calling from Dover, New Hampshire. Alejandro Vélez: That is a ...

Two related frog species differ by chromosome number, which deepened one species's calls and tells the females who's who. Steve Mirsky reports The eastern grey tree frog (sound) looks exactly like the ...