SCIENCE LAB SCAMPER : TURTLES EVOLUTION

Turtle That Took 

To The Water.

Inhospitable conditions prove a boon to paleontologists 150 million years later.

Today it is Bavaria, a region in Germany. But in the late Jurassic Period, it was a shallow tropical archipelago ringed with sponge reefs. The hypersaline, oxygen-poor conditions of the waters prevented scavengers from disturbing the bodies of animals that died in the lagoons.

Some 150 million years later, that has been very good news for paleontologists, who for more than 100 years have pulled complete fossils of animals as fish, reptiles, pterosaurs and feathered dinosaurs like Archaeopteryx from the Solnhofen limestone.

The area's latest find is a beautifully preserved -if pancaked- turtle.

Described in an article in the journal PLOS One, it represents an approach to marine life unlike that of any shelled reptile today.

The turtle's name is Solnhofia, said Felix Augustin, a paleontologist at the University of Tubingen in Germany and an author of the study.

Originally named in 1975, for decades the creature was known only from a pair of skulls and some fragments.

But the new Sonhofen specimen- which was recovered by a private collector from a quarry near the German city of Painten - is the entire nine-inch animal.It is also '' the best one preserved so far,'' said Marton Rabi, a paleontologist also at the University of Tubingen and another author of the study.

'' Modern sea turtles have near global distribution and do these insanely long migrations. They're also adapted to a marine lifestyle, '' Dr. Rabi said.

'' These marine Jurassic sea turtles were not capable of that.''

And yet, such coastal, clawed marine turtles were successful throughout the remainder of the Mesozoic Era.

Solnhofen has preserved other examples of the first sea turtles, which evolved from a terrestrial lineage before adapting to a freshwater and then to shallow marine environments like those found in Jurassic Bavaria.

'' In this Southern German region, the diversity of sea turtles is surprisingly high,'' Dr. Rabi said. These turtles differed significantly from their distant modern relatives.

The animals lacked the stiffened paddles that would appear on open water turtles in the Cretaceous Period, and may have also lacked specialized salt-removal glands found in modern sea turtles. [ Asher Elbein ]