for National Geographic News
It weighed 17,500 pounds (7,938 kilograms), was 40 feet (12.2 meters) long, and probably ate dinosaurs for dinner.
Sarcosuchus imperator, an ancient relative of modern alligators and crocodiles that roamed the Sahara Desert 110 million years ago, had jaws of steel that no preynot even small dinosaurscould pry open, according to researchers. Being trapped in the jaws of this monsterdubbed "SuperCroc" by paleontologistswould be equivalent to being trapped under the weight of a Mack Truck, explained Greg Erickson, a biologist at Florida State University.
Erickson and his colleagues extrapolated the bite force of SuperCroc from data they collected by provoking living alligators and crocodiles at a zoological park in Florida to chomp on a "bite bar." Basically a rod encased in leather, the instrument measures bite force strength in much the same way a bathroom scale measures weight.
In April 2002, Erickson and his colleagues took to the unbound lakes and rivers of central Florida to see if wild alligators bite with more force than those kept in captivity.
The original researchwhich was filmed for a National Geographic Special on SuperCroc that aired in December 2001 on the National Geographic Channel, and which will be repeated at 8 p.m. and 11 p.m. ET/PT, April 6, 2003 and 5 p.m. ET/PT April 12was conducted at the St. Augustine Alligator Farm and Zoological Park in Florida.
There, Erickson and his colleagues Kent Vliet, a zoologist at the University of Florida in Gainesville, and Kristopher Lappin, a biologist at Northern Arizona University in Flagstaff, wrestled more than 60 crocodilians to shore long enough to induce them to chomp viciously on the seven-foot-long (two-meter-long) bite bar.
The bar has four piezoelectric sensors, shaped like washers, that are sandwiched between two steel plates. "When the animal bites the plates and squeezes them together, we get a reading," said Lappin. "The four sensors are wired together so that a bite anywhere on the plates will give an accurate reading of the force."
The trick is to get the crocodiles or alligators to bite the bar.
To do so, the researchers sling a rope around the creature's neck and pull it ashore, where Vliet jumps on the animal's back.
"I have to get onto the animal's back before we place the bite bar to try to prevent the animal from rolling when it does bite and possibly breaking our equipment," he said. Each bite bar costs up to U.S. $10,000, depending on size.
SOURCES AND RELATED WEB SITES