The two newly described ancient penguins were found in the Atacama Desert in Peru. With just tens of millimeters of precipitation a year, the Atacama is the driest desert in the world. Some parts haven't seen rain for an estimated 40 million years.

Geologists say the Atacama is also the oldest desert on Earth. Its long-term stability is attributed partly to a cold, upwelling offshore current that may have insulated it from the dramatic temperature changes of the ice ages.

Temperatures in the desert region vary widely between its barren coastal plains, its white-capped volcanoes, and the region where it gives way to the foothills of the Andes mountain range.

—Anne Minard

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