There are many fossil evidences to prove this habit. Some fossil excavations with high concentration of ichthyosaurs show that ichthyosaurs will use certain places as production sites year after year. Another piece of evidence comes from modern animals; Some sharks will lay eggs or give birth in shallow water with environment in Gramineae, because the coral in shallow water can be used as a shelter for newborns to avoid predators. The reason why the baby big-eyed ichthyosaur in the film will stay away from the adult big-eyed ichthyosaur immediately after being born is also from fossil evidence. Because some ichthyosaurs are found in their bellies, cannibalism is the only explanation.