Fossils from the oldest known Antarctic “sea monster” have been found, a new study says.
The discovery of an 85-million-year-old plesiosaur has pushed back the marine reptile’s presence in Antarctica by 15 million years.
"The fragments we found don’t belong to any group registered on the continent before, which indicates a greater diversity of the plesiosaurs in Antarctica than previously suspected," said team leader Alexander Kellner, of the National Museum of Brazil at the Federal University of Rio de Janeiro.
Fragments of the vertebrae, head, and flippers suggest the newfound plesiosaur was 20 to 23 feet (6 to 7 meters) long. The bones weren’t, however, enough to identify the species of the plesiosaur.
Plesiosaurs roamed the seas worldwide between about 205 million to 65 million years ago, reaching the Southern Hemisphere by the mid-Jurassic. The animals had a range of different sizes and features, but mostly shared small heads, long necks, and big bodies.
"If the Loch Ness monster ever existed, this would be its best representation," Kellner said. Read more.
Like whales, humans, and most other mammals, plesiosaurs—giant, long-necked marine reptiles of dinosaur times—gave birth to live young, a new fossil study suggests.
Even as it apparently solves one mystery, though, the finding raises another: Did the “sea monsters” swam in mother-child pairs or even in larger groups, like modern whales and dolphins?
The study focused on a 78-million-year-old, 15.4-foot-long (4.7-meter-long) adult Polycotylus latippinus plesiosaur fossil found in 1987. The fossil’s abdominal cavity contains tiny bones—parts of a plesiosaur that hadn’t been born by the time its mother died.
The finding, detailed in this week’s issue of the journal Science, is the first proof that plesiosaurs were viviparous—that they gave birth to live young.
"The fetus is too large to make an egg physiologically or mechanically feasible," study co-author Robin O’Keefe told National Geographic News. "And why carry a big egg around?" Read more.
Packing what may be the world’s biggest bite, a recently revealed “sea monster” would have given Jaws a run for its money.
Put on display July 8 at the U.K.’s Dorset County Museum, the 7.9-foot-long (2.4 meter-long) skull (pictured) belonged to a pliosaur, a type of plesiosaur that had a short neck, a huge, crocodile-like head, and razor-sharp teeth. When alive about 155 million years ago, the seagoing creature would have had a strong enough bite to snap a car in half, according to the museum.
Amateur collector Kevan Sheehan found the skull in pieces between 2003 and 2008 at the Jurassic Coast World Heritage Site, a 95-mile (152-kilometer) stretch of fossil-rich coastline in England. The Dorset County Council’s museums service purchased the fossil, and later research by University of Southampton scientists suggests that it’s the largest complete pliosaur skull ever found. Read more.