Dimetrodon, Early Permian, around 280 million years ago

Long before the dinosaurs, Dimetrodon dominated the terrestrial ecosystems of the Permian. This imposing synapsid, often mistakenly thought of as a reptile, is actually much closer to us on the tree of life than any dinosaur. This illustration depicts it at the edge of a stream, its large dorsal sail in orange hues catching the warmth of the morning sun. Below the water's surface, primitive fish move through a world just as fascinating.