for National Geographic News
With its body obscured by murky waters, an ancient fanged reptile may have used its long neck to lunge at fish and squid. The scenario is based on analysis of a 230-million-year-old fossil discovered in southeastern China.
The new creature appeared long before the dinosaurs and is named Dinocephalosaurus orientalis, which means "terrible headed lizard from the Orient." It was a protorosaur, part of an order of diverse, predatory reptiles that lived as far back as 280 million years ago.
The ancient reptile had short and broad limbs with relatively few bones in the wrist and ankle joints, an indication that it was more adapted to an aquatic lifestyle than other protorosaurs. (Scientists say living aquatic reptiles may have fewer bones in wrists and ankles than their terrestrial counterparts.)
Dinocephalosaurus also had a relatively stiff neck that was about 5.5 feet (1.7 meters) long. That's nearly twice as long as its trunk, which was three feet (one meter) long. Several thin and flexible rib bones, called cervical ribs, ran along the neck portion of the creature's spine, each bridging several of its 25 neck vertebrae.
"Protorosaurs as a group all have at least somewhat elongated neck vertebrae," said Olivier Rieppel, curator of fossil amphibians and reptiles at the Field Museum in Chicago. Rieppel is co-author of the paper that describes the fossil, which appears in tomorrow's issue of the journal Science.
His past research projects have been funded, in part, by grants from the National Geographic Society's Committee for Research and Exploration.
For years scientists have struggled to explain the functional significance of the elongated necks common to these reptiles. Analysis of the new fossil by Rieppel and his colleagues offers a solution to the enigma: The feature may have helped protorosaurs hunt.
The mystery surrounding the protorosaurian neck dates back to Tanystropheus longobardicus, a protorosaur from Europe and the Middle East discovered in the 1850s.
Tanystropheus had 12 "grotesquely elongated" neck vertebrae. Scientists could only explain then as a consequence of growth patterns but not as serving any specific purpose, Rieppel said. As in Dinocephalosaurus, cervical ribs in Tanystropheus bridged multiple vertebrae.
After comparing the Dinocephalosaurus fossil to living animals and thinking about how the creature fed in murky coastal waters, Rieppel and his colleagues believe they have discovered a more specific function for the elongated necks.
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