"With Eorhynchochelys's
diapsid skull, we know that turtles are not related to the early anapsid reptiles (those without openings), but are instead related to evolutionarily more advanced
diapsid reptiles," Rieppel concluded. Modern-day snakes and lizards also evolved from the
diapsid population.
Traces attributed to apterygote insects, arthropleurid myriapods, bivalved arthropods and vermiform animals occur in lake-margin sediments in association with those of temnospondyl amphibians and early
diapsid reptiles, and belong to the Scoyenia ichnofacies.
When all of the data -- much of it provided by deBraga, whose research focuses on Paleozoic reptiles -- was crunched through the computer, "we found that turtles flipped from anapsid to
diapsid," Rieppel explains.
(1999): A long-necked
diapsid reptile from the Upper Jurassic/ Lower Cretaceous of Liaoning Province, north-eastern China.
That means one-way airflow may have arisen not among the early archosaurs about 250 million years ago, but as early as 270 million years ago among cold-blooded
diapsids, which were the common, cold-blooded ancestors of the archosaurs and Lepidosauromorpha, a group of reptiles that today includes lizards, snakes and lizard-like creatures known as tuataras.