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Prehistoric Predecessors to Today's Animals

The ancestors of some species were very different from those we know today!

Published September 21, 2016

Species continue to evolve from their prehistoric predecessors. However, you may not even recognize some distant relatives of today’s animals.

Take this prehistoric sea turtle as an example. While today’s sea turtles grow, on average, to be less than 1,000 pounds, this turtle was a whopping 9.8 feet long! Locating the full fossilized skeleton for this massive turtle took 163 years. Upon completion it was deemed to be the largest sea turtle ever found. In studying the turtle, it was determined that the closest living relative to the species is the loggerhead sea turtle.loggerhead-sea-turtle

Similarly, sloths have a gigantic ancestor, aptly named the giant ground sloth. Based on specimens collected, these animals grew as long as 8 to 10 feet in length! Fossilized remains of these sloths have been found across the United States, all the way from the East Coast to present day Alaska. One type of giant ground sloth, the megalonyx, meaning "great claw," was named by Thomas Jefferson in 1797 after remains were found in a cave in Virginia.giant-ground-sloth-skeleton

Both the sea turtle and the giant sloth are distant relatives to animals you can see at the Aquarium! The Linne’s two-toed sloths and our loggerhead turtle, Sheldon, both call the Aquarium home.sloths

To read more about the ancient sea turtle, click here, and for more on the giant sloths, click here!

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