“Turtles evolved a body plan so successful that they have remained largely unchanged since the time of dinosaurs. Turtle shells, made of bones fused with their ribs, obviously protect vital organs against predators. But the protective ability of the turtle’s skull—far greater than other animals’—was a surprise that has triggered scientists to take a closer look at the skull’s architecture and engineering.
CT scans reveal that the skulls have a fairly extensive broad shelf of bone that may reflect shockwaves away from the brain, Ketten said. ‘The turtle skull even reminds you of some of the helmets used in World War I, with a flange in back.’ Or, the skulls, made of fused bone plates, might be constructed in a way that makes them flexible in the face of pressure waves and resistant to breaking, she said. “We don’t yet know.”
More than shape may be involved. On each side of their skulls, sea turtles have large glands that produce salty tears to keep their body fluids in balance. These “big balls of tissue of either side of the brain” may in some way act as shock absorbers, Ketten said” (Woods Hole Oceanographic Institution, n.d.).
Reflection Question:
Why do you think sea turtles have evolved to have such a shock-absorbent skull? What evolutionary advantage would this serve in the ocean?
References:
Woods Hole Oceanographic Institution. (n.d.-b). Turtle Skulls Prove to be Shock-Resistant. https://www.whoi.edu/oceanus/feature/turtle-skulls-prove-to-be-shock-resistant/