Scientists have unearthed the remains of a freshwater shark that inhabited the rivers of South Dakota a whopping 67 million years ago. They have named it after the popular 1981 Japanese-U.S. game Galaga.
The shark was discovered in the same pile of ancient sediment as Sue the Tyrannosaurus rex, the famous dinosaur known as Specimen FMNH PR 2081 which currently resides at the Field Museum of Natural History in Chicago, Illinois. Apparently, this freshwater shark from the Cretaceous Period, had teeth that resembled the iconic 1980s Galaga video game space fighter. It was these very teeth that gave the creature its name-- Galagadon nordquistae.
The classic arcade game, Galaga, pit insectoid alien spaceships against a spacecraft at the bottom of the screen - controlled by the player - which bears a strong resemblance to the shark teeth.
According to new research published in the Journal of Paleontology, the shark was not very big, measuring around 12 to 18 inches in length and searched the riverbed for small fish, snails, and crayfish. The scientists who discovered Galagadon said the shark is related to modern-day carpet sharks, with the mottled patterns on their body evocative of carpet designs.
Despite having been discovered in the same place as Sue, there is no suggestion the shark had any interaction with the enormous predatory dinosaur beyond living in the river from which it may have drunk.
“Galagadon was not swooping in to prey on T. rex, Triceratops, or any other dinosaurs that happened into its streams,” said Dr Terry Gates, a palaeontologist at North Carolina State University who led the study.
“This shark had teeth that were good for catching small fish or crushing snails.”
The teeth, which were no bigger than pinheads, were all that remained of the ancient fish, as shark skeletons are made of cartilage which does not fossilize well. As for Karen Nordquist, a Field Museum volunteer who helped discover the fossils, she said that the teeth were really difficult to see.
“To the naked eye, it just looks like a little bump, you have to have a microscope to get a good view of it,” she said.
Scientists believe the shark had a flat face and mottled colouration that would have allowed it to lie hidden at the bottom of the river. Besides revealing a new species of shark, they say their discovery also provide new evidence of the Cretaceous habitat in which Sue the T. rex lived – alongside rivers that were not far from newly formed oceans.
“The more we discover about the Cretaceous period just before the non-bird dinosaurs went extinct, the more fantastic that world becomes,” said Dr. Gates.