The Cambrian fossil record indicates that most animal phyla had diversified and inhabited the Earth's oceans approximately 518 million years ago. But even though chordates—the group that includes vertebrates like humans—were part of this early animal...
A vein-filled rock is catching the eye of the science team of NASA's Perseverance rover. Nicknamed "Cheyava Falls" by the team, the arrowhead-shaped rock contains fascinating traits that may bear on the question of whether Mars...
