A huge clam with a shell in the form of a paper clip lived for 200 years in the Cretaceous period. This was figured out by a couple of researchers from Syracuse University. Linda Iwani and Emily Artruk talked about their work at the Geological Society of America online meeting this year, Science X reports.
The species, which scientists called Diplomoceras maximum, lived about 68 million years ago in waters near present-day Antarctica. By the way, he lived at the same time as Tyrannosaurus rex, in the Upper Cretaceous.
D. maximum was a large squid-like creature – its shell was over 1.5 meters in height. He was an ammonite and part of the now-extinct group of tentacled cephalopods. D. maximum died out at the same time as the dinosaurs, presumably for the same reason – due to the collision of the Earth with an asteroid, which formed the impact crater Chikshulub.
What made Diplomoceras stand out was the unique shape of its shell. The top is curved both back and forth to resemble a paper clip. In this new work, scientists have discovered something else remarkable about the ancient creature – its lifespan.
A pair of researchers studied the shell of a specimen that had been previously discovered by other researchers. As part of their work, they investigated its chemical composition. Scientists have discovered repeating isotope signatures. The researchers speculate that the signatures were formed from methane that enters the water every year from the seabed. Methane left a trail annually covering the D. maximum shell. By adding up the number of methane ridges on the shell, the researchers were able to calculate its age. They found that D. maximum survived to about 200 years.