Ctenophores and Ancient Species: Surviving 700 Million Years

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Horseshoe crabs remained unchanged for 230 million years, surviving five mass extinctions in shallow coastal waters.

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Coelacanths first appeared 400 million years ago and were rediscovered off South Africa's coast in 1938.

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A 9cm fossil cockroach, twice the size of modern American roaches, was found in Ohio's ancient tropical swamps.

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Scientists identified ctenophores as Earth's oldest living creature, emerging 700 million years ago.

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These jellyfish-like creatures travel ocean depths exceeding four miles using eight rows of specialized cilia for movement.

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Genome research revealed ctenophores branched off before other animal lineages on the evolutionary tree.

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Ctenophore chromosomes share particular gene combinations with non-animal organisms, unlike other animals.

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These marine creatures process food through nutrient-distributing canals without a true digestive system.

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The ctenophore Mnemiopsis leidyi caused fish population declines after entering the Black Sea in the 1980s.

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These ancient organisms developed their nerve nets independently from other animals' nervous systems

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