A newly discovered species of ancient shark has been named after a 1980s arcade game. The shark swam in the rivers of what is now South Dakota, US, about 67 million years ago, living alongside iconic dinosaur species such as T. rex. It's been named Galagadon, after the 1981 Japanese-US game Galaga, because its teeth resemble the spaceships in the game. The specimen is described in the Journal of Paleontology. "It may seem odd today, but about 67 million years ago, what is now South Dakota was covered in forests, swamps and winding rivers," said co-author Terry Gates, from North...