When it comes to turtle shells, the first thing that crosses our minds is "shield," but it turns out, they were evolved for digging, not protection.
A new study from Denver Museum of Nature and Science by an international group of paleontologists suggests that the broad ribbed proto shell on the earliest partially shelled fossil turtles was initially an adaptation for burrowing underground.
Lead author Tyler Lyson said, "Why the turtle shell evolved is a very Dr Seuss-like question and the answer seems pretty obvious - it was for protection, but just like the bird feather did not initially evolve for flight, the earliest beginnings of the turtle shell was not for protection but rather for digging underground to escape the harsh South African environment where these early proto turtles lived."
Lyson noted, "We knew from both the fossil record and observing how the turtle shell develops in modern turtles that one of the first major changes toward a shell was the broadening of the ribs."
The study appears in journal Current Biology.
