Dinosaur neck size reaches new extreme

Scientists have unearthed remains of a massive, plant-eating dinosaur whose neck may have measured twice the length of its body.

Herbivorous dinosaurs called sauropods are noted for their massive bodies and long necks. However, the partial remains of Erketu ellisoni, excavated from 100-to-120-million-year-old sediments in Mongolia, set a new record for neck-to-body proportions among the sauropods, says Daniel T. Ksepka, a vertebrate paleontologist at the American Museum of Natural History in New York.

Remains of the specimen include only six neck bones, the longest of which measure 49 centimeters. That dimension—plus the expectation that E. ellisoni had 15 neck bones, as its closest relatives did—suggests that the creature’s neck may have been as much as 7.8 meters long, says Ksepka.

Dimensions of other bones, including the partial remains of one of E. ellisoni’s hind limbs, suggest that the sauropod’s body was only about half the length of its neck. Although other sauropod species had necks that were longer than E. ellisoni’s, none of their necks was so lengthy in comparison with its body.

Ksepka and museum colleague Mark A. Norell describe E. ellisoni in the March 16 American Museum Novitates.