Fossils Flesh out Early Vertebrates
Bower, Bruce, Science News
Fossils flesh out early vertebrates
The oldest known vertebrates, a collection of remarkably well-preserved remains of 30 jawless fish, have been discovered by an international team of paleontologists in the mountains of southern Bolivia, according to an announcement last week by the National Geographic Society in Washington, D.C., which funded the expedition.
The fossils were embedded in large stone slabs that date to about 470 million years ago, when much of present-day Bolivia was covered by ocean. At least 10 of the specimens are virtually complete, with even the tail sections intact, says expedition director Philippe Janvier of the French National Research Center in Paris.
"This is one of the most exciting and important discoveries in lower-vertebrate studies in the last 50 years," says vertebrate paleontologist David K. Elliott of Northern Arizona University in Flagstaff, who has seen the Bolivian specimens.
These ancient fish were probably poor swimmers that avoided deep water, notes Janvier. Bony plates protected the rounded head of the creature. Its body was covered with thin scales that ended near a narrow tail.
The fossil fish, which are up to 18 inches long and 6 inches wide, appear to represent a new genus, according to Janvier. He and his co-workers have dubbed the genus Sacabambaspis, after a village located near the fossil discovery. …