This picture of fossilized crinoids was taken at the Sternberg Museum of Natural History, in Hays, Kansas.

Crinoids are marine animals that are still alive today, even though their ancestors emerged during the early Cambrian, some 540 million years ago. They are echinoderms, related to starfish and sea urchins. They feed by filtering small particles of food from the sea water with their feather like arms and their tube feet are covered with a sticky mucus that traps any food that floats past.

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