24. Watch out for the “mouse lizard” for #Sauropodocember ! Here’s #Mussaurus (“mouse lizard”), a sauropodomorph from the Late Triassic Period of Argentina. Photo credit to @NHMdinolab.

It receives its name from the small size of the skeletons of juvenile and infant individuals, which were once the only known specimens of the genus.

However, Mussaurus is now known from adult specimens, with the adults possibly measuring 20 feet long and weighing more than 2,000 pounds. Artwork by randomdinos.

Mussaurus specimens have been found in association with nests, believed to contain multiple eggs, with the infants measuring 7 to 14 inches long. Artwork by Davide Bonadonna.

A common feature in dinosaurs, Mussaurus had tall skulls with short snouts and large eyes, whereas the adults had long snouts and long necks. Artwork by @SerpenIllus.

Interestingly, a 2019 study showed that throughout the ontogeny of Mussaurus, the infants were quadrupedal during the first year of its life, only to transition to a bipedal stance later in life. Illustration by González. (1/3)

Here’s a paper by authors on the ontogenetic biomechanics of Mussaurus by Alejandro Otero, @AndrewRCuff, Vivian Allen, Lauren Sumner-Rooney, @poldiego, and @JohnRHutchinson. (2/3) https://www.nature.com/articles/s41598-019-44037-1

This may help us understand how sauropods evolved their quadrupedal gaits.(3/3)