The mouth of a child is a terrifying thing to behold

Inside the mouth of every child is a terrifying double row of teeth. Not that you'd ever know it — muscle, skin and bone prevent most of us from ever catching a glimpse of this extra dentition. Here's your chance to get a close-up look at what lies beyond the gum line. » 5/17/12 2:00pm 5/17/12 2:00pm

Grass-eating hominid was the primate equivalent of a cow

Although the ancient hominid Paranthropus boisei has earned the nickname "Nutcracker Man", his actual diet was quite a bit softer. Unlike any other known human ancestor, this ancient hominid's powerful jaw and huge molars were actually used to eat grass. » 5/02/11 1:12pm 5/02/11 1:12pm

"Hammer-biter" marsupials were a weird mix of mammal and lizard

The marsupials and monotremes that are now found primarily in Australia represent a sort of evolutionary middle ground, mixing together their mammalian features with those of reptiles or amphibians. One ancient marsupial represents a particularly weird case of convergent evolution. » 4/21/11 4:30pm 4/21/11 4:30pm