Sea monster fossil sheds light on old mystery

<body leftmargin="0" bgcolor="#000060" text="#FFFFFF" link="#FFFF00" vlink="#FF9900"> <b> <p class="MsoNormal"><font face="Arial" size="4">Sea monster fossil sheds light on old mystery</font></b> </p> <p class="MsoNormal"><font face="Arial" size="1">Posted Sept. 23, 2004<br> Courtesy the Field Museum of Chicago<br> and World Science Staff</font> </p> <p class="MsoNormal"><b><font size="2" face="Arial">An extinct sea monster used its long neck to creep up on prey with its head and suck them in, scientists suggest, based on a new fossil find.</font></b></p> <p class="MsoNormal"><b><font size="2" face="Arial">The creature is a member of the Protorosauria, a group of predatory reptiles and distant relatives of dinosaurs that lived as far back as 280 million years ago. </font></b></p> <p class="MsoNormal"><b><font size="2" face="Arial"> Scientists have never been able to figure out the function of the extremely long neck that characterizes some species of this group. <br> <br> The fossil suggests the long neck may have been part of a unique and very effective method for capturing prey in water. <i>Dinocephalosaurus orientalis</i>, which means "terrible-headed lizard from the Orient," was recently discovered in southern China. In a paper in the Sept. 24 issue of the research journal <i>Science</i>, researchers describe how the neck may have been used to capture prey. <br> <br> "This is important research because we have finally explained the functional purpose of this strange, long neck," said Olivier Rieppel, PhD, a co-author of the Science paper and chair of geology and curator of fossil amphibians and reptiles at Chicago's Field Museum. "It allowed an almost perfect strike at prey, which usually consisted of elusive fish and squid." <br> <br> Prey in water is slippery, and any movement toward it not only alerts the prey of an attack but also creates a pressure wave that could push the prey away. Fish and some turtles combat these factors with suction feeding, i.e., pulling the prey into their months by rapidly expanding the mouth cavity. <br> <br> Crocodiles and alligators use a different approach. They catch prey with their flat head and pincer jaws, which allow them (when feeding in water) to strike from the sides, cutting through the water while minimizing the force that pushes the prey away. <br> <br> <i>Dinocephalosaurus</i> apparently had yet another tactic. When it thrust its head forward to capture prey, the ribs along its neck would splay outward. This would create a suction that would draw in water, along with the prey. <br> <br> In addition, the long neck allowed Dinocephalosaurus to draw near its prey stealthily so it would have less of a chance of being detected. "To a fish in murky water, Dinocephalosaurus' head would have initially looked like another animal its own size, but by the time the fish was able to see Dinocephalosaurus' body, it would already have been lunch," said Michael LaBarbera, professor of organismal biology and anatomy at the University of Chicago. <br> <br> <i>Dinocephalosaurus</i>' neck measures 1.7 meters, while its trunk is less than 1 meter long. Unlike most protorosaurs, <i> Dinocephalosaurus</i> was fully aquatic, although it might have laid its eggs on land.  </font></b></p> <p class="MsoNormal"> <b> <font size="2" face="Arial"><a href="http://groups.yahoo.com/group/world-science">http://groups.yahoo.com/group/world-science</a></font> </b> </p> </body>