Earlier than thought: Turtle shells moved back to 260 million years ago
|November 18, 2013||Posted by News under News, stasis|
Forty million years earlier than previously reckoned.
Could someone please develop this into a theme song? Put it up at YouTube?
Their detailed study of Eunotosaurus indicated it uniquely shared many features only found in turtles, such as no intercostal muscles that run in between the ribs, paired belly ribs and a specialized mode of rib development, which indicates that Eunotosaurus represents one of the first species to form the evolutionary branch of turtles.
“Eunotosaurus neatly fills an approximately 30-55-million year gap in the turtle fossil record,” said Tyler Lyson, a Peter Buck Postdoctoral Fellow at the Smithsonian’s National Museum of Natural History. “There are several anatomical and developmental features that indicate Eunotosaurus is an early representative of the turtle lineage; however, its morphology is intermediate between the specialized shell found in modern turtles and primitive features found in other vertebrates. As such, Eunotosaurus helps bridge the morphological gap between turtles and other reptiles.”
Note: As usual, the release doesn’t say what these features are or why they are considered “primitive” when they appear in other vertebrates. Usually things do not turn out that way as the story unfolds (or in some cases, unravels).