One of the most cuddly early animals might have been a pack-hunting cannibal.   

Those cute critters of the early Earth may have been roving packs of cannibals, according to new evidence on trilobites.  Teeth marks, attack positions, shredded relatives and other signs of cannibalism have been found in the fossilized remains of tiny agnostid trilobites, affectionately called "bugs" by paleontologists and fossil hunters.

Earth's Early Cannibals Caught in the Act