Scientists from the University of Texas at Austin have finally solved the mystery of a massive fossil that has been sitting unlabeled and unidentified at a Chilean museum for almost a decade. The relic, which resembles a deflated football, is the largest-known soft-shelled egg from a marine reptile that inhabited Earth over 66 million years ago — about the time of the mass animal extinction event. Measuring more than 11 by 7 inches it is also the second-largest egg belonging to any known animal, behind only the now-extinct elephant bird.