A brand new research by College of Alberta paleontologists reveals that one kind of historic reptiles developed a particular kind of tooth enamel, just like that of mammals, with excessive resistance to put on and tear.
|Fossilized enamel from the traditional lizard Priosphenodon present that it had sturdy tooth enamel—a characteristic a lot
extra widespread in mammals, in keeping with U of A paleontologists [Credit: Aaron LeBlanc]
The reptile—referred to as Priosphenodon—was a herbivore from the Late Cretaceous interval that was about one metre lengthy. A part of a bunch of reptiles referred to as sphenodontians, that they had the distinctive trait of including new enamel to the again ends of their jaws as a substitute of changing them the place they fell out.
“Priosphenodon has the strangest enamel I’ve personally ever seen,” mentioned Aaron LeBlanc, a post-doctoral fellow in organic sciences and lead writer on the research. “Some points of their dental anatomy are paying homage to what occurred within the evolution of early mammal enamel.”
The specimens have been present in Argentina’s Rio Negro province as a part of ongoing collaborative fieldwork and analysis between U of A paleontologist Michael Caldwell and Argentinian paleontologist and fieldwork chief Sebastian Apesteguia.
To look intently on the enamel of Priosphenodon, the researchers reduce open items of jaw and examined tissue-level element preserved contained in the enamel, and used non-invasive CT scans to look at extra full jaw specimens.
“Priosphenodon enamel will not be solely thicker than that of most different reptiles, the enamel crystals are ‘woven’ into lengthy threads that run by means of the entire width of the enamel. These threads are referred to as enamel prisms, and they’re virtually solely present in mammals,” mentioned LeBlanc, who’s working below Caldwell’s supervision.
“Our outcomes counsel that sturdy selective pressures can power reptiles to provide you with some very progressive options to the issues related to tooth put on and abrasive diets—a few of which mirror what occurred in our earliest mammal ancestors.”
The scientists additionally famous there may be one sort of lizard alive at the moment that has prismatic enamel like Priosphenodon—the spiny-tailed lizard of Australia. Like Priosphenodon, it principally eats vegetation and has misplaced the power to exchange its worn enamel. Nonetheless, the 2 reptiles usually are not intently associated.
Hans Larsson from McGill College additionally collaborated on the research, which was funded by the Agencia Nacional de Promocion Cientifica y Tecnologica in Argentina, Nationwide Geographic and the Pure Sciences and Engineering Analysis Council of Canada.