Mesozoic Earth - Elasmosaurus courtship

Location North America 80 million years ago Mean atmospheric O₂ 150% of modern level Mean atmospheric CO₂ 6x pre-industrial level Mean temperature 4°C above modern level		Geologic Time Scale Era: Mesozoic Period: Cretaceous Epoch: Late Age: Campanian

	Elasmosaurus courtship A pair of 40-foot-long plesiosaurs of the genus Elasmosaurus engage in a swimming courtship dance in a secluded saltwater lagoon 80 million years ago in what is today North America.* The gull-like toothed seabirds are from the genus Ichthyornis, the Cretaceous ecological equivalent of modern gulls, petrels, and skimmers. At over two tons, Elasmosaurus was an air-breathing carnivorous reptile with flippers for limbs and a relatively small head with sharp teeth. More than half of its length was neck which had more than 70 vertebrae, more than any other animal. While Elasmosaurus* is believed to have lived mostly in open ocean, here the artist is suggesting that these two have retreated to secluded lagoon for a romantic rendezvous, though there is no paleontological evidence supporting this behavior.