One of the World's Oldest Animal Fossils Discovered
Description:Scientists have uncovered one of the oldest animal fossils ever. Research findings claim the fossil is that of a 520-million-year-old sea creature. The fossil is a type of arthropod, but it has primitive limbs under the head. Its nervous system reaches past the head into the body. Scientists believe the animal might have used its limbs to push foods into its mouth while exploring the sea floor. (1:12)