There’s a lot to admire about turtles and tortoises. They seem to have a steadfast character, and a plodding yet undeniable gait that sooner or later gets them to where they are going. Here are some other facts about these creatures that may make you scratch your shell in wonder.
Testudo, the Latin word for tortoise, shell, arch or vault, was also the name given to a technique used by Roman soldiers in warfare. Standing close together, in the shape of a rectangle, they held their shields flat over their heads, to form a protective dome, allowing them to approach the enemy en masse, unharmed by spears, stones and arrows.
The black soft-shelled turtle figures importantly in Hindu mythology. The animals are believed to represent the souls of long ago sinners, transformed into reptiles by a 13th century saint, are in a tank attached to a temple in Bangladesh. Each animal is considered sacred, and so none can be removed.
The oldest known tortoise may have been a radiated tortoise from Madagascar (Astrochelys radiata), which died in 1965. She was at least 188 years old, having been given to the Tonga royal family, by Captain Cook in 1773 or 1777.
The Galapagos tortoise is the largest living species, weighing in some cases, over 570 pounds.
The carapace or upper shell of the tortoise or turtle is composed of about 50 bones, which include modified ribs, vertebrae and bony skin plates. The lower shell or plastron has evolved from the clavicles or collarbones and the ribs. The bony structure joining the two is called the bridge. The shell is very much alive, not dead tissue, like nails or hair.
The growth rings on the scutes or scales on a tortoise cannot be used to determine the animal’s age with any degree of accuracy, as in most instances, growth spurts and interruptions in growth are determined largely by environmental conditions.
In leatherback and soft-shelled turtles, the bony scutes have been replaced with tough, leathery skin.
Some species have hinges on either the carapace or the plastron, which allow closure of the shell.
The snapping turtle (Macroclemys sp.) has a worm-like, fleshy structure on its tongue, which it wiggles to attract fish.
Turtles cannot protrude their tongues from their mouths, but they can smell. Flapping the loose skin under the chin or throat moves air over the Jacobsen’s organ.
Tortoises and turtles do not have teeth.
Tortoises store sperm and have been known to produce fertile eggs three years after the last mating.
Stupendemys geographicus was a prehistoric turtle that was 10 feet long and probably weighed 4,000 to 5,000 pounds.