Sharks might not be a natural biological group, with most species potentially closer kin to rays than to an oddball group of sharks.

The dinosaur lineage has provided us with some of the most truly terrifying animals to ever walk the planet. But we eventually learned that all birds are actually theropod dinosaurs. Looking at ...

Thirteen million years ago, a group of medium-sized monkeys known for guarding their territory among the treetops with fearsome "howls" started doing something new. These monkeys, among the oldest ...

Steve Nix is a member of the Society of American Foresters and a former forest resources analyst for the state of Alabama. Leaf shapes play an important role in tree identification, providing key ...