evolution

Like many of us, Earth bears old pockmarks. Our planet’s crust has a band of ancient craters that formed around 465 million years ago. The divots were created at a time when animals in the seas were taking on a broad array of…

An artist's concept of early earth as a pale orange dot some 4 billion years ago.NASA/Goddard Space Flight Center/Francis Reddy Carbon Dioxide is often vilified as a bugaboo greenhouse gas. But its presence here on early earth is likely…

Two ecotypes of Littorina saxatilis marine snails, adapted to different environments. The Crab ecotype (left) is larger and wary of predators. The Wave ecotype (right) is smaller and has bold behavior. © David Carmelet KLOSTERNEUBURG,…