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Changing Seas
Sponges: Oldest Creatures in the Sea?
Season 8
Episode 801
Recent DNA research has cast doubt on the theory 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. Recently, some scientists are suggesting that ctenophores, also known as comb jellies, are an older lineage.
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26:43
Discover what lives beneath the Blue Heron Bridge in Florida.

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26:43
Visit the remote Pacific, the islands of Maug - a natural laboratory for scientists.

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26:43
Scientists take advantage of manatee gatherings to study them.

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26:43
Discover how some fish species change their sex.

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26:44
Researchers provide data necessary to protect fish populations from further decline.

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26:42
Researchers study what impact ecotourism might have on southern stingrays.
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Researchers are beginning to understand where turtles go during their “lost years.”

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26:54
Scientists conduct research to save the Smalltooth Sawfish.

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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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26:48
Discover Crinoids which have been around since before the age of Dinosaurs.

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26:46
The Changing Seas team meets with researchers in French Polynesia.