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Changing Seas
Sponges: Oldest Creatures in the Sea? - Trailer
Until recently there was scientific consensus that sponges were the first animals to branch off the “Animal Tree of Life,” a kind of family tree for all living and extinct animals on earth. But recent DNA research has cast doubt on that theory, with some scientists suggesting that ctenophores, also known as comb jellies, are an older lineage.
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27:02
Scientists spend a month in the Galapagos Islands to conduct research.
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26:54
The world’s largest known aggregation of whale sharks occurs just off the coast of Cancun.
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29:33
Scientists work to identify and link a devastating coral disease to a human pathogen.
