Graze anatomy: the prehistoric preference for eating plants

Graze anatomy: the prehistoric preference for eating plants
simocuhus clarki, an 80 million year old vegetarian crocodile

Despite images of T-Rex and velociraptors burned into our brains by movies such as Jurassic Park, etc., scientists now think that more dinosaurs were actually vegetarians than originally thought, especially those that eventually evolved into birds. According to a new report scheduled for release in the journal Proceedings of the National Academy of Science, paleontologists Peter Makovicky and Lindsay Zanno of the Field Museum in Chicago, Il “used statistical analysis (such as studying teeth, neck length and overall skeletal structures) from nearly 100 coelurosaurs in order to determine the dietary preferences of 90 species of theropods--bipedal, bird like dinosaurs that first appeared in the late Triassic period.” These creatures roamed the earth from approximately 145 million to 65 millions years ago

As a result, the pair found that “44 theropod species in six different lineages (including the ancestors of most modern birds) were not solely carnivores, but at the very least omnivores. Most theropods are clearly adapted to a predatory lifestyle, but somewhere on the line to birds, predatory dinosaurs went soft," Zanno told the AFP on Monday

"Once we linked certain adaptations with direct evidence of diet, we looked to see which other theropod species had the same traits… then we could say who was likely a plant eater and who was not," she added. "This new research firmly supports what we've have been speculating about for some time… it's time to start seeing these animals in a new evolutionary context."

Macovicky and Zanno also found that many of the therapods may have gone from eating meat to becoming vegetarians, then switched back to being carnivores (or at least omnivores, eating both) to survive over thousands, if not millions of years, in order to survive as their world changed.

In addition, a separate team of scientists from Stony Brook University on Long Island have just released information regarding the discovery of an 80 million year old vegetarian crocodile on Madagascar in the Journal of Vertebrate Paleontology. Dubbed simocuhus clarki, the four foot long, pig-nosed creature had a “tank-like body and short stubby tail, and lived life more like an armadillo than a conventional croc,” according to paleontologist David Krause. “No other crocodile looks Crocodiles evolved into a wide variety of body plans in the Age of Dinosaurs, but this one really looks unusual."

In addition Nathan Kley, confirmed that simosuchus clarki’s short snout “served for chewing vegetation, too weak to snatch up other animals.”

To learn more about dinosaurs here in Connecticut check out Dinosaur State Park in Rocky Hill at http://www.dinosaurstatepark.org/ as well as The Dinosaur Place in Montville at http://www.thedinosaurplace.com

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