A newly described amphibious stem-insect fossil had 24 legs, shedding light on how the ancestors of modern insects moved from water onto land.

Imagine the Western Plains of North America, from Texas to Alaska, submerged under a broad, shallow seaway. To the west lay the ancestral Rocky Mountains. To the east were low-lying plains traversed by large, sluggish rivers.

New work argues the first bird reached takeoff speed with two or three leaps rather than a standing launch.

The first thing that the expedition team found in peeking from the rocks and sands of the Gobi Desert was a tiny tip of a large pelvis. The international team descended on the exposed fossil, and chipped and brushed away to reveal more and more bones. Eventually, they exposed an exceptionally rare find: the virtually complete skeleton of a new dinosaur species.

Nearly a quarter billion years ago an otter-sized, armored, platypus-faced, marine reptile paddled in tropical lagoons on the shores of islands that would become southern China. This weird species is part of a diverse lineage that was restricted to a few million years and those tropical lagoons.

Wadi Al Hitan, the Valley of the Whales, is a site that’s yielded dozens of skeletons of the early predatory whales Basilosaurus and Dorudon over the last hundred years. Newly uncovered specimens support the idea that it was a calving ground for the dolphin-sized Dorudon, and that those calves were hunted by the much larger Basilosaurus.