Unique among Earth’s creatures, turtles are the only animals to form a shell on the outside of their bodies through a fusion of modified ribs, vertebrae and shoulder girdle bones. The turtle shell is a unique modification, and how and when it originated has fascinated and confounded biologists for more than two centuries.
OFFICIAL Denver Museum of Nature & Science : Early Origins of Turtles
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OFFICIAL Denver Museum of Nature & Science : Early Origins of Turtles
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