Elasmosaurus

Elasmosaurus was about 10.3 meters (34 feet) long, with its neck alone around 7.1 meters (23 feet). That is longer than a school bus.1

Elasmosaurus probably ate small fish and marine invertebrates, seizing them with its long teeth. It may have used stomach stones to help digest its food.12

No, Elasmosaurus was a plesiosaur, a marine reptile that lived in the sea. It was not a dinosaur, though it lived during the time of dinosaurs.13

No, Elasmosaurus could not raise its head and neck high above the water like a swan. Its neck was too heavy and not flexible enough, so it could only lift its head above water in very shallow water.1

Elasmosaurus had 72 neck vertebrae, which is the second largest number known in any animal. Its relative Albertonectes had even more, with at least 75.1

Elasmosaurus lived in the Western Interior Seaway, a shallow sea that covered the middle of North America about 80.6 to 77 million years ago. Its fossils have been found in Kansas, USA.1

Scientists are not sure why Elasmosaurus had such a long neck. It may have helped in feeding, perhaps by sneaking up on prey, but the exact reason is unknown.12

Edward Drinker Cope, who named Elasmosaurus, mistakenly put the skull on the tail end of the skeleton in his reconstruction. This famous error was pointed out by his rival Othniel Charles Marsh.1