evolution– tag –

A bird opens its wings. A bat does the same. Look more closely, however, and different structures come into view: the bird spreads feathers, while the bat stretches a thin membrane supported by remarkably long fingers. They achieve the s...

Cover photograph by Simone Dinoia Sleep takes time away from finding food, moving about and watching for danger. Yet humans and many other animals regularly make time for it. Sleep—or a state with some of its defining features—has been r...

In the cool, rain-soaked forests of southern Chile and Argentina lives a tiny marsupial with rounded ears, dark rings around its eyes and a long tail that helps it move through branches. It is called the monito del monte—roughly, “little...