Some harlequin frogs have lost their poison—and their ability to defend themselves. Scientists are on the case.

Deep in the tropical forests of Colombia, you come across a small, beautiful frog. You’re captivated by its brilliant color and reach out to hold it in your hand. Within seconds, your hand starts to ...

The frogs belong to the Atelopus group from Central and South America.

Scientists have discovered a new species of poisonous frog—brightly colored and measuring just a few millimeters—in the Amazon, according to a Peruvian government agency in charge of environmental ...

This newly discovered poison frog may represent an evolutionary step on the pathway towards developing brilliant warning coloration associated with other poison dart frogs. A small reddish-brown frog ...