Nearly a decade ago, a mysterious of 66 million-year-old fossil was discovered in Antarctica and was recently found to be one of the biggest eggs ever recorded. Back in 2011, a group of researchers were exploring the southern frozen continent looking for fossils of marine reptiles, when they came across a weird looking fossil. It was almost a foot wide and looked like a deflated football.
Until recently, the team of researchers analyzed samples, finding multiple membrane layers in the fossil, proving that it was indeed an egg. Its features are similar to that of eggs laid by some modern-day lizards and snakes. Based on an analysis of 259 modern reptiles and their eggs, a giant sea creature known as a mosasaur would seem to match description.Mosasaurs are an extinct species of large marine reptiles that lived in the dinosaur era in Antarctica. Data showed the reptile that laid the egg was at least 23 feet long from the tip of its snout to its tail. Furthermore, the rock formation where the egg was discovered also hosts skeletons from baby mosasaurs and plesiosaurs, along with adult specimens.