You Share 70% of Your Genes with This Slimy Marine Worm

Clearly, acorn worms look nothing like people; the worms have no limbs and breathe through slits in their guts. But they share approximately 14,000 genes with humans, scientists found, comprising about 70 percent of the human genome. These genes can be traced back to an ancestor of both acorn worms and humans that lived more than 500 million years ago, during a period known as the Cambrian explosion.