It's an old story. An animal or plant is discovered in sedimentary rocks by paleontologists and it pushes the organism's origin further back by many millions of years—but it's always a plant or animal already known to science. Granted, some of these fossilized creatures are extinct, but that's no indication they evolved.

On January 21, 2015 the news broke—an Australian fisherman hooked a "living fossil." Called the frilled (or frill) shark (genus Chlamydoselachus, belonging to Order Hexanchiformes), this creature was thought to be 80 million years old.¹ It looks mighty frightening, but is it truly "prehistoric" and somehow linked to shark evolution?

Clovers come in a wide variety of sizes, and some of them hold interesting surprises. Plant biologists have been studying one trait in particular, and it keeps showing up—or disappearing—in peculiar patterns. Do these patterns illustrate evolutionary changes or does something entirely different switch off this trait?

Nineteenth-century English poet Alfred Tennyson famously described nature as "red in tooth and claw."¹ But were claws and teeth originally intended to draw blood, or were they used to eat vegetation?