“Supershark” Fossils Found in Texas
The fossilised remains of two braincases from an extinct species of shark have revealed that long before the Age of the Dinosaurs these top marine predators were reaching impressive lengths. In a bizarre quirk of fate the announcement of these new Texan fossils was made at the annual meeting of the Society of Vertebrate Paleontology being held this year in Dallas, Texas.
These ‘supersharks’ are preserved as two large brain cases originally recovered from Jacksboro, Texas. Both were then generously donated by their owner to the American Museum of Natural History for study. By comparing these braincases to the more complete remains of smaller, related shark species it was possible for the research team to estimate just how large these sharks were in life. The results were impressive with estimates of their lengths varying between 5-8 metres. The largest of the two specimens was around 25% larger in life then a modern Great White. Naming the precise species that these two braincases belonged too has been harder, but the team suggest that they either belonged to Glikmanius occidentalis, an extinct ctenacanthid shark, or a larger, previously unknown relative. Similar fossils, albeit smaller, have also been recovered from Scotland suggesting that once these animals were a wide-spread and successful group.
While these new fossils don’t reach anything like the mammoth proportions of the largest shark to ever live, Megalodon, these are far, far older. Despite measuring an impressive 20 metres tip to tail Megalodon occurred relatively recently in geological terms, going extinct only around 2 million years ago during the Pleistocene. Even most modern large sharks can only trace their ancestry back as far as the Jurassic-Cretaceous around 100 million years ago. In contrast these new specimens date back 300 million years making them the oldest large sharks ever discovered. At the time the area which is now Texas was covered by a warm, shallow ocean and these sharks would have been the apex predators.
Source: Society of Vertebrate Evolution
Featured Image: Modern Great White Shark. Source: Wikimedia Commons