Episode 214 is all about Thecodontosaurus, a Triassic sauropodomorph discovered in 1830s England.

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In this episode, we discuss:

Best discovery: Ledumahadi source

2nd best discovery: Jinyunpelta source

Best listener question: What species of modern bird is the closest living relative of theropods, or more specifically raptors?

Most controversial paper: Spinosaurus probably couldn’t swim very well source

Best dino food study: Dromeosaurs probably didn’t pack hunt source

Best dinosaur biomechanic study: “Puncture-and-Pull Biomechanics” source

Best paleopathology study: Diplodocus femur and hip pathologies source

Best new tracksite: Goddard Space Flight Center tracks source

Best extinction paper: How widespread forest fires affected bird evolution source

Best baby dinosaur discovery: A nestling-sized skeleton of Edmontosaurus source

Best Book (fiction): Bolivar (published end of 2017) source

Best Book (non-fiction): The Rise and Fall of the Dinosaurs

Best board Game: Jurassic Park: Danger source

2nd best board game: Cluedo: The Stolen Stegosaurus Mystery game source

Best Video Game: Jurassic World: Evolution

Best movie release: Jurassic World: Fallen Kingdom

Best Video (live action): Jurassic World Fallen Kingdom parkour

Best Video (animated): College Humor Jurassic Park with other prehistoric creatures

2nd best Video (animated): Jurassic Park in heels

Best story about dinosaurs bringing people together: A four-year-old received over 100 dinosaur toys after his house burned down

Sauropodomorph that lived in the Triassic in what is now England

Small, bipedal

About 3.9 ft (1.2 m) long, weighed about 24 lb (11 kg)

Largest ones estimated to be 8.2 ft (2.5 m) long

Had a short neck and large skull, with large eyes

Front limbs were shorter than hindlimbs

Hands were long and narrow, and had a large claw on each

Had five digits on its hands and feet

Tail was longer than the rest of the body

Had powerful back legs, could reach low hanging tree branches

Maybe could have swam? Used its tail as a rudder and strong limbs for swimming

Lived on a tropical island

Herbivorous

Had serrated, leaf-shaped teeth

Sharp teeth could tear up leaves

Originally thought to be carnivorous

Name means “socket-tooth lizard”

Found in 1834 at the Durdham Down quarry

Originally described and named in 1836

One of the first dinosaurs discovered (fourth or fifth named dinosaur, though Dinosauria as a concept didn’t exist until 1842)

Thecodontosaurus was at first thought to be a weird reptile that was similar to both lizards and crocodiles

Quarry workers found “saurian animals” remains in Bristol’s limestone quarries. They took some bones to the Bristol Institution for the Advancement of Science, Literature and Arts, so Samuel Stutchbury could see them. He was away, so his colleague Henry Riley took a look. When Stutchbury came back, he asked for more specimens. David Williams, a country parson and geologist, was aso excited. So there was a race between Williams and Stutchbury and Riley to describe the bones.

Stutchbury and Williams didn’t trust each other (Williams thought Stutchbury was selfish in trying to get all the fossils to the Bristol Institution, and Stutchbury thought Williams was trying to poach fossils). They both worked on descriptions of the dinosaur. However, Williams didn’t have as many fossil material as Riley and Stutchbury so he didn’t try to turn his report in 1835 into a legitimate description of the animal. Riley and Stutchbury named Thecodontosaurus and gave a short description in a talk in 1836 then finished their paper in 1838 and published in 1840

Name refers to the roots of the teeth not being fused with the jaw bone but instead in separate tooth sockets (like modern lizards)

Originally Riley and Stutchbury though it was a member of Squamata (lizards and snakes). Owen did not consider it to be a dinosaur (assigned it to Thecodontia in 1865). Then in 1870 Thomas Huxley found it was a dinosaur, though thought it was a Scelidosauridae. Modern analysis is still not conclusive (sometimes seen as a basal sauropodomorph, or may have come before the prosauropod-sauropod split)

Only one valid species, the type species Thecodontosaurus antiquus (though many other species have been named)

Species named in 1843 by John Morris, in his catalogue of British fossils

Species name means “ancient” in Latin

Holotype consists of a lower jaw

Holotype was destroyed in WWII in November 1940 during the Bristol Blitz

Some bones survived (184 are now part of the Bristol City Museum and Art Gallery, and more fossils were later found near Bristol at Tytherington)

About 245 fragmentary specimens are currently known

Peter Dalton assigned another lower jaw as the neotype in 1985

Lots of other misassigned species, some now considered to be other genera, some are dubious

Riley and Stutchbury also found some carnivore teeth that they named Paleosaurus cylindrodon and Paleosaurus platydon. In the late 1800s, there was a theory that they were from carnivorous prosauropods, with similar bodies to Thecodontosaurus but with teeth that could slice. Arthur Smith Woodward named Thecodontosaurus platydon in 1890 based on this, and Friedrich von Huene named Thecodontosaurus cylindrodon in 1908, but now they’re both not considered valid

Once, Thecodontosaurus fossils were mistakenly described as a different genus. In 1891, Harry Govier Seeley named Agrosaurus macgillivrayi. He thought the fossils found in 1844 that came from the northeast coast of Australia. But it was foun in 1999 that Riley and Stutchbury probably sent those bones to the British Museum of Natural History and were mislabeled. (In 1906, Friedrich von Huene said they were similar to Thecodontosaurus and named the species Thecodontosaurus macgillivrayi. Now it’s considered a junior synonym of Thecodontosaurus antiquus.

Part of the Bristol Dinosaur Project, which for ~4 years thousands of volunteers helped gather and preserve its fossils (lots of lab, research, and outreach work)

Thecodontosaurus

Fun Fact: From episode 180: Stegosaur plates form from the same osteoderms that make up the armor on ankylosaurs

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This episode is brought to you in part by TRX Dinosaurs, which makes beautiful and realistic dinosaur sculptures, puppets, and animatronics. You can see some amazing examples and works in progress on Instagram @trxdinosaurs

And by Indiana University Press. Their Life of the Past series is lavishly illustrated and meticulously documented to showcase the latest findings and most compelling interpretations in the ever-changing field of paleontology. Find their books at iupress.indiana.edu