Otavia antiqua. Image Source: Gizmodo.
Gizmodo reports on a 760 million year old animal, a sponge that was the original life form from which all other animals evolved:
"Scientists believe that this is the animal from which everything else evolved. The first multicellular being that spawned every living being in this world through billions of mutations, from fish to amphibians to reptiles to birds to mammals to you. It's an amazing discovery. Its name is Otavia antiqua, and it is the oldest animal ever discovered: 760 million years old. Scientists claim that it used to chill out in calm, nice, shallow waters, chewing on algae and bacteria through its pores and into its little tube body."