Scientists working in the Antartic have recently unearthed the most complete fossil of an elasmosaur ever found. Elasmosaurs, members of the plesiosaur family, roamed the oceans during the Cretaceous Period, between 66 and 145 million years ago, roughly the same time period that dinosaurs walked the Earth. They must have looked very much like the proverbial sea monster. This one would have weighed a hefty 15 tons, making it at least five tons heavier than any plesiosaur ever found. The specimen also dates to 70 million years, near the end of the Cretaceous, making it a crucial find in the ongoing debate over what killed the dinosaurs.

A thirty-year mystery

The huge skeleton was originally discovered in 1989, by William Zinsmeister, a researcher at Purdue University. However, its location in the Antartic meant digging it up was no simple task. Harsh weather conditions, including temperatures that can reach 100 degrees below Fahrenheit, and unpredictable snow storms, limited the project’s work to the summer months, January and February. Even on a pleasant Antartic summer day, the team of paleontologists had to wait around most of the morning for the ground permafrost to thaw before they could resume the dig. Progress was incredibly slow.

As a result, it was thirty years before anyone could definitively say what Zinsmeister had found was an elasmosaur. Team leader Jose O’Gorman notes, “For years it was a mystery […] we didn’t know if they were elasmasours or not […]. They were some kind of weird plesiosaurs that nobody knew.”

Famous cousins

For years many cryptozoologists have argued that the famous Loch Ness Monster is an elasmosaur. The idea, however unlikely it might seem, is that one of the creatures somehow managed to survive from the Cretaceous Period. There certainly are some striking resemblances between the two creatures. The elasmosaur, for instance, had a long, almost giraffe-like neck and four flippers, which does resemble some local descriptions of Nessie.

Mainstream researchers, however, describe the elasmosaur as similar to a manatee, only with a much longer neck – as long as 23 feet in some cases – and a flat, triangular, snake-like head. Of course, unlike the manatee, which is a mammal, elasmosaurs were reptiles and some of the largest creatures to ever inhabit the Earth.

Secrets still to unlock

Having now been completely unearthed, the bones of the massive skeleton currently reside in a museum at the Marimbio Base in Argentina. There, paleontologists are only now beginning to unlock new secrets about life in the sea during the Cretaceous Period.

Some of these secrets seem fairly mundane, The find is unusual, for instance, in that, while plesiosaurs have been found in relative abundance in the Netherlands and even in America, they are much rarer in the Southern hemisphere. This find suggests there may be more to discover in the still relatively unexplored Antartic.

Sometimes, though, seemingly unimportant discoveries can yield vital information. One of these small discoveries is the fact that the elasmosaur had small teeth. Its diet must have been limited to crustaceans and small fish. For a reptile of this size to have survived, its environment must have been absolutely teeming with marine life, and that gives scientists important clues about where that life went 66 million years ago.

The biggest secret of all

Beyond its size and location, the most significant aspect of the find may have to do with its age. Dating has placed the creature’s demise at a mere 33,000 years before the end of the Cretaceous Period. This fact suggests that marine life was thriving even up until the very moment dinosaurs went extinct. This adds fuel to the argument that the dinosaurs were destroyed in a single event, perhaps an asteroid strike on the earth. Some scientists have argued that dinosaur populations were already beginning to weaken before this so-called K-T event, but the existence of the elasmosaur so close to this event suggest ecosystems all over the planet were still thriving.

Such evidence lines up with the claim made earlier this year by Robert DePalma, that he had discovered fossil evidence in North Dakota from the very day of the extinction event.