One of the world's largest collections of fossilized mollusks from the Antarctic has been donated to the Paleontological Research Institution (PRI), a Cornell-affiliated institution. This collection can help shed new light on extinction and climate change as it occurred in the past.
The collection of Cretaceous to Eocene mollusk fossils from Seymour Island, Antarctica, was donated by William J. Zinsmeister, a professor of geology at Purdue University. It is widely recognized as among the largest and finest collections in the world from this region.
The collection will allow for new research collaborations. PRI plans to create an online exhibit of the collection to highlight its importance for discussions of climate change, evolution and extinction.
The collection is important for two reasons, said Gregory Dietl, director of collections at PRI. "The first is that it includes samples from one of the best K-T boundary sections [the time interval when dinosaurs became extinct] in the world. Recent discoveries from Seymour Island are challenging the view that the K-T extinctions were caused solely by a catastrophic asteroid impact. Instead, a prolonged interval of decline in diversity, prior to the impact event at the end of the Cretaceous Period 65 million years ago, is evident from the fossil record on Seymour Island.
"These data suggest that more protracted changes in the Earth's climate may also have been important."
The second reason the collection is important, he said, is that it can help researchers to understand the effects of current climate change on marine communities in Antarctica.
"Today global warming is enabling crab predators to reinvade Antarctica, after being excluded from the region following the onset of a cooling event in the Eocene some 40 million years ago. Scientists are trying to understand how the indigenous fauna will respond to such changes. The collection's strength during this critical interval in the history of the Antarctic region provides unique information to addressing this problem," he said.
Among the most notable fossils in the collection is the heteromorphic ammonite ( Diplomoceras ), which is related to the living nautilus. One specimen measures about 6 feet in length and resembles a saxophone.
"It boggles the mind," said Dietl. "It makes one wonder how did that organism live; was it able to swim? Most ammonites could swim, but this specimen makes you wonder."
PRI's collection of fossils is one of the largest in North America. Over the course of the next several years, PRI will begin the process of making the Zinsmeister collection publicly available.