Paleontologists have returned from the Antarctic Peninsula with a scientific treasure trove. It will take years to reveal all the finds, including whether any new dinosaur species are included. However, after two journeys frustrated by bad weather, paleontologists are excited by what they call “really great fossils”.
Prior to this year's expedition, “most of what has been found in Antarctica has been invertebrates, bivalves and such like,” Dr. Steve Salisbury of the University of Queensland told IFLScience. “There were several dinosaur fossils found in the mid-'80s, but not much else.”
Consequently, there has been ample enthusiasm for more, but the hostile climate has proven a challenge. Thick ice makes most of Antarctica off-limits to fossil hunters, but large parts of the Antarctica Peninsula, and nearby islands, are ice-free in summer. However, ventures to the continent in 2013 and 2014 were defeated by thick sea-ice blocking ships' passage. “Glaciers melting increases the amount of ice at sea, and the tightening of the circum-Antarctic winds cool the surface water, so paradoxically warmer temperatures result in more sea ice,” said Salisbury
This year's expedition, though, had both better luck and helicopter support, yielding more than a tonne of fossils.
“The rocks that we were focusing on come from the end of the Age of Dinosaurs, so most of them are between 71 million and 67 million years old,” Salisbury said in a statement. “They were all shallow marine rocks, so the majority of things we found lived in the ocean.”
The richest finds were plesiosaurs, including one unusually intact shoulder girdle helicoptered off the side of a mountain. There were also remnants of mosasaurs, the marine reptiles who starred in Jurassic World.
Salisbury told IFLScience that little is known about which dinosaur species are represented in the haul. The precious cargo is now in Chile en route to the Carnegie Museum of Natural History.
Although Antarctica was warm 70 million years ago, it still experienced months of near-total darkness each year. Despite this, Salisbury told IFLScience, “The dinosaurs, and marine reptiles, that have been found there previously are very similar to others with no obvious specializations for the conditions.” It is unclear if they migrated north in the winter, or had some other survival mechanism.
Salisbury told IFLScience that when looking for fossils in such an unexplored area, “the first thing is to go to areas where fossils have been found in the past, and then target places we have a suspicion have the right type of rocks. A lot of the rocks down there have been mapped to some degree.”
However, Salisbury added that erosion is so fast on the Peninsula that many previously mapped areas had changed dramatically, necessitating slow, systematic searchs over largely unknown areas.