Scientists have long thought the humble sea sponge, an animal that feeds by filtering water through itself, forms the oldest group of animals on earth. But a new study claims that the comb jelly phylum is in fact older and carries genetic material from distant, non-animal ancestors.
Comb jellies, which look like miniature jellyfishes, use rows of cilia hairs to swim through the ocean and catch prey with tentacles that release a sticky, mucous-like substance. Like other animals, they meet the standard of having developed from a fertilized egg into a multicellular organism.