A 26 cm long reptile found in Germany ran on two even before the dinosaurs
13.11.2000
by Tamara Traubman
Scientists believe they have discovered the first creature that walked on two legs. The creature, which until now was unknown, was a small, vegetarian reptile that lived about 290 million years ago - almost 80 million years before the dinosaurs, which until now were considered the first creatures to walk on two legs.
"The exciting thing is that this is an example of the first animal known to us, which could stand on its two hind legs and run fast," said Prof. Robert Rees, one of the researchers, in an interview from his office at the University of Toronto in Massaga.
In the study, published today in the scientific journal "Science", the researchers, led by Prof. David Berman from the Carnegie Museum in the USA, write that the entire length of the small reptile, Odibamus corsoris, was about 26 centimeters. It belongs to a large family of very ancient reptiles called bolusaurids. Unlike its relatives that have been discovered in many parts of the world, including North America, China and Russia, it runs on its hind legs while its arms swing at the sides of its body like a pendulum.
"Modern lizards run with their legs bent and facing the sides. We think that the legs of this reptile were placed in a straight line under its body, and in this respect it ran like a dinosaur, or a mammal, basically like us," said Prof. Rees.
The ability to walk on two legs gave the little reptile the ability to run fast and escape madmen. Prof. Rees says that the creature was discovered in a quarry in the city of Gotha in Germany, "along with many other large and carnivorous vegetarian reptiles that must have tried to catch this little brat". Scholars believe that when Oedibamus had no reason to hurry, he walked on all fours.
The evidence that he walked on two comes from a careful examination of the remains of his bones, which were remarkably preserved almost intact. In the examination, it turned out that the hind limbs of the Odibamus were 60% longer than its front legs, and 34% longer than its body. These proportions are similar to those of modern bipedal lizards and are also typical of bipeds in general. The toes of the Odibamus were also comparatively very long. The researchers believe that he actually ran on his toes and thus took advantage of their length to lengthen his steps. Oedibamus' tail, which is more than half of its body length, helped it maintain its center of gravity at the waist and stay balanced.
Prof Rees said he and his colleagues worked for two years to clean the fine remains of the fossil under the microscope. "Even before we realized that we had something truly unique, but we couldn't identify it, because it was embedded in a rock." According to him, so far they have not found remains of other species at the site from the time they walked on two, but it is possible that another find discovered this year will turn out to be Oedibamus.
The appearance of the Odibamus reminds a contemporary lizard called the "crucified Jesus lizard" (or basilix), which can run fast on water. "We compared our fossil to the Crucified Jesus Lizard," says Rees, "and in fact, the proportions of Odibamus are even more adapted to running on two than the Crucified Jesus Lizard."
"The Oedibamus was not the ancestor of the dinosaurs," points out Ariel Chipman, a doctoral student at the Hebrew University who studies vertebrate evolution. "Both adapted to walking on two independently, which shows that throughout evolution, completely separate groups can reach similar solutions."
{Appeared in the Haaretz newspaper, 3/11/2000{ - The Hidan site was until 2002 part of the IOL portal from the Haaretz group
