
JEREMY GAY
3 DAYS AGO
A team of researchers has determined that comb jellies, Ctenophores, were the first animals on earth, existing 700 million years ago, and pre-dating sponges by 100 million years. They are also the most recent common ancestor of all animals, (including ourselves,) and can still be found in the oceans today. This may lead to a better understanding of how all animals evolved.
Scientists had narrowed the earliest animals down to two groups – ctenophores and sponges, Comb jellies differ from true jellyfish in that they propel themselves with eight rows of cilia, whereas Jellyfish propel themselves by squirting water. In an evolutionary timeline, Ctenophores appeared first, then sponges, then worms, at 500m years, with the first vertebrates appearing 450 million years ago. The dinosaurs appeared 230m years ago. Despite the discovery, there is no fossil record for Ctenophores as their soft bodies were not preserved. The links were made instead using living Ctenophores and by comparing their genomes.
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Ctenophore Comb Jellies declared First Animals on Earth, 700m years ago | Reef Builders | The Reef and Saltwater Aquarium Blog
A team of researchers has determined that comb jellies, Ctenophores, were the first animals on earth, existing 700 million years ago, and pre-dating sponges by 100 million years. They are also the…
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