Episode 435: Spinosaur brains, Tyrannosaurus species update, and paleo advancements. Gregory S. Paul joins us to discuss his work including the recent controversial Tyrannosaurus rex, regina, and imperator paper. Plus a review of the history of dinosaur paleontology and what advancements are coming for CT scanners

News:

• Phil Currie wrote an amazing review article about the history of paleontology, what we now know about dinosaurs compared to when humans first discovered dinosaurs, and where the field of paleontology is headed source
• A new study of spinosaur brains and skulls helps show how they adapted to eat fish source
• Trinity the Tyrannosaurus will be auctioned off in Switzerland next month source

Interview:

Gregory S. Paul, researcher, author, and illustrator. He’s known for his research on theropods, writing the books Predatory Dinosaur of the World and The Princeton Field Guide to Dinosaurs, consulting with Jurassic Park and When Dinosaurs Roamed America, and creating many illustrations. He was part of the Dinosaur Renaissance and his work helped show dinosaurs as more active and bird-like.

Sponsors:

You can dig up real dinosaur bones this summer with Colorado Northwestern Community College! Join them for a two week immersive field paleontology experience digging up dinosaur bones from the Jurassic period in Northwest Colorado. There are two scheduled digs: May 27–June 11 and July 1–July 16. There are also two concurrent immersive lab techniques programs available. Get all the details and register online at cncc.edu/dinodig

The dinosaur of the day: Tianyulong

• Heterodontosaurid ornithischian that lived in the Late Jurassic in what is now Western Liaoning Province, China
• Looked somewhat similar to Heterodontosaurus, with long legs and a long tail, and a short skull, but had shorter arms and a shorter neck
• Probably walked on two legs
• Like other heterodontosaurids, had a pair of large, canine-like tusks
• Had unusual proportions compared to its heterodontosaurid relatives, with a large head, long legs and tail, but short arms and a short neck
• Holotype was mature and estimated to be about 27.5 in (70 cm) long, based on comparisons to its relative Heterodontosaurus tucki
• Skull was similar in shape to Heterodontosaurus
• Skull is about 2.3 in (6 cm) long
• Tail is about 17 in (44 cm) long
• Arms are less than 30% the length of the legs
• Tail is similar to dromaeosaur theropods, with a more mobile base and middle and end being more rigid
• May have helped with balance
• Had a long second finger
• May have been good at grasping
• Heterodontosaurids were herbivores, and maybe omnivores
• Heterodontosaurids have bills for cropping, well developed cheeks, good for eating plants
• Type and only species is Tianyulong confuciusi
• Fossils found in Jianchang County and are now at the Shandong Tianyu Museum of Nature
• Skeleton lay flat on a slab of rock
• Genus name means Tianyu dragon
• Genus name refers to the Tianyu Museum of Nature
• Species name is in honor of Confucius
• Named in 2009 by Zheng Xiao-Ting and others
• First heterodontosaurid found in what is now Asia
• Originally thought to be from the Early Cretaceous, then later found to be from the Tiaojishan Formation (about 158.5 million years ago)
• Holotype is an incomplete skeleton including part of the skull and jaw, vertebrae, part of the arm, part of the pelvis, part of the legs and feet, and long filamentous integumentary structures (possible proto-feathers)
• In 2012, Paul Sereno did a study of heterodontosaurids and described a second specimen of Tianyulong
• Second specimen includes a nearly complete skull, vertebrae, part of the tail, shoulders, most of the arms, and parts of the legs and feet
• Holotype and second specimen are about the same size
• There are at least four other undescribed specimens
• Sereno said all the specimens must be studied to have a reliable skull reconstruction
• Most interesting part of the find were the feather-like structures
• Found three patches of long, filamentous structures on its back, tail, and neck
• Structures look similar to protofeathers
• Not quite a feather. Feathers are flexible and have vanes, and the structures on Tianyulong are stiff and don’t have vanes (flat part on the side of a shaft of a feather)
• They are single structures with no branches
• Unusual to find an ornithischian with feathers (usually have found saurischians, mainly theropods, with evidence of feathers)
• Ornithischians include ankylosaurs, stegosaurs, ceratopsians, hadrosaurs, and heterodontosaurids
• Psittacosaurus is another ornithischian, a ceratopsian, with bristles on its tail
• Patches found on Tianyulong are similar to the bristles on Psittacosaurus
• Also similar to structures found on some theropods, like Sinosauropteryx and Beipiaosaurus
• More similar to the bristles on the tail of Psittacosaurus than to protofeathers in theropods, though the structures on the tail of Psittacosaurus are more rigid and more widely separated from each other
• The ones on the tail of Tianyulong are the longest, at about 60 mm long, which is seven times the height of the tail vertebra
• Structures were possibly for display (definitely not for flight)
• Finding them opened up new questions, like whether ornithischians independently evolved these structures or if these structures were part of the common ancestor of ornithischians and saurischians (meaning, did all dinosaurs evolve from an animal with these structures)
• Heterodontosaurids are basal ornithischians, which adds to the debate

Fun Fact:

The technology to look inside dinosaur skulls without breaking them open is over 50 years old, but it wasn’t regularly used until more recently.

Thank you Patrons!

Your support means so much to us and keeps us going! If you’re a dinosaur enthusiast, join our growing community on Patreon at patreon.com/iknowdino