Turtles Carry Their Homes

How the Turtle Got Its Shell, With Apologies to Aesop

By Hans-Dieter Sues Smithsonian.com

Turtles stand alone among living and extinct backboned animals because of the unique hard shell that encases their bodies. Other animals, like the armadillo, evolved body armor, but the turtle shell fully integrates the backbone and trunk ribs.

The turtle shell is made up of rows of firmly connected bony plates, which are covered by horny plates, or scutes. The domed carapace covering the back of the animal is connected to the flat plastron on the underside of the animal by a bridge of bone. The resulting box encloses the shoulder and hip girdles, but is open at the front for the head, neck and forelegs, and at the back for the tail and hind legs.

How did this unusual structure evolve? One of Aesop’s fables tells of the wedding of Zeus and Hera. Hermes had invited all the animals, but the turtle did not show up. When an angry Hermes demanded to know why it had not come to the feast, the turtle responded that it preferred its own home. Enraged, Hermes made the animal carry its house forever after.

Carol Duff, MSN, BA, RN

Carol graduated from Riverside White Cross School of Nursing in Columbus, Ohio and received her diploma as a registered nurse. She attended Bowling Green State University where she received a Bachelor of Arts Degree in History and Literature. She attended the University of Toledo, College of Nursing, and received a Master’s of Nursing Science Degree as an Educator.

She has traveled extensively, is a photographer, and writes on medical issues. Carol has three children RJ, Katherine, and Stephen – one daughter-in-law; Katie – two granddaughters; Isabella Marianna and Zoe Olivia – and one grandson, Alexander Paul. She also shares her life with her husband Gordon Duff, many cats, and two rescues.

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