Episode 205 is all about Yamaceratops, a ceratopsian whose frill is heavily pitted, possibly for jaw muscle attachments.

We also interview Ali Nabavizadeh, Assistant Professor of anatomy at Cooper Medical School of Rowan University. He studies the jaw musculature of herbivorous dinosaurs. Follow him on Twitter @Vert_Anatomist, check out his blog Anatomist’s Guide, or his Google site.

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In this episode, we discuss:

News:

• A large sauropod from the Late Cretaceous has been found in the Gobi Desert and it’s about 30-40% complete source
• In Argentina 70 million year old dinosaur eggs were found possibly including embryos, skin, and teeth source
• The “Tufts-Love” T. rex skull at the Burke Museum has found 100% of the skull and jaw bones by bone count including several that are rarely preserved source
• Junchang Lü, one of the most prominent paleontologists in China, recently passed away at the beginning of October at the age of 53 source
• Chilesaurus diegosuarezi, the first Jurassic dinosaur found in Chile, is going on exhibit at the Regional Museum of Aysen, in Coyhaique, Chile, next year source
• An Allosaurus will be posed with a nest at the Smithsonian National Museum of Natural History since it may have looked after its young source
• Jurassic World is selling Indoraptor masks, just in time for Halloween source
• A study of 150 Ceolophysis—mostly from the same bonebed—show that early triassic dinosaurs had femora that changed significantly as they aged source
• The data used to support the Ornithoscelida hypothesis had many errors, which casts some doubt on the conclusion that Ornithoscelida should replace the traditional Saurischia and Ornithischia groups source
• A study of a baby Massospondylus and it’s forelimb strength shows that Massospondylus was bipedal for its entire life source
• A simulation of Mussaurus (the earliest Jurassic sauropodomorph) showed its center of mass shifted as it grew, meaning that it was quadrupedal as a baby and bipedal as an adult source
• Researchers used a program called niche mapper to model microclimates of Plateosaurus & Coelophysis, showing which environments they would prefer based on plumage and metabolic rates source
• Reconstructions of dinosaur feeding musculature shows that they chewed in a way different than any animal alive today source
• A study of emu and ostrich bones found many similarities with dinosaurs and suggests using bone microstructure to identify maturity source
• Sauropodomorph inner ears vary significantly across groups: Diplodocoids have relatively smaller inner ear, while Giraffatitan has the largest known inner-ear source
• By studying alligator and turkey arms we might be able to show which theropods could supinate their hands as they drew them to their body source
• A study of dinosaur bearing sites from Dinosaur Park Formation in Alberta & Saskatchewan and the similar aged Judith River sites in Montana shows which locations were the most similar source
• A new model of dinosaur diversity in the latest cretaceous shows that they were not in decline, but instead maybe slowing down or leveling off source

The dinosaur of the day: Yamaceratops

• Neoceratopsian
• Lived in the Late Cretaceous in what is now the Gobi Desert, in Mongolia
• Found a skull in the 1991 American Museum of Natural History–Mongolian Academy of Sciences expedition
• Members of those expeditions came back in 2002 and 2003 and found more Yamaceratops material
• Not enough fossils to know its size
• Herbivorous
• Had a relatively thick rostral that had a rugose (wrinkled) texture
• Had a frill, that may not have been used for display but rather “hints at a more complex evolutionary history for ceratopsian frills”
• Edge of the frill is “heavily pitted by muscle insertions, indicating that the frill served as a platform for large jaw adductors”
• Had a distinct epijugal ossification (armored cheek plate), and is the most basal neoceratopsian with this
• Frill and cheeks suggest more variety in psittacosaurids and neoceratopsians than previously thought
• Described in 2006 by Makovicky and Norell
• Type species is Yamaceratops dorngobiensis
• Name means Yama horned face
• Name refers to Yama, a Tibetan Buddhist deity, who is the Lord of Death and one of the eight protectors of Buddhist teaching, and who has the head of a water buffalor and has horns (like ceratopsians)
• Species name refers to the Eastern Gobi
• Originally thought to be from the Early Cretaceous, but a later study found it to be Late Cretaceous
• Scientists found a fossilized egg and embryo in an area where Yamaceratops were commonly found
• A later study with more CT scans found that the egg was actually of a bird, not Yamaceratops

Fun Fact:

The K-Pg extinction event was unremarkable for an aquatic extinction (but still unusual for a terrestrial extinction).

Sponsors:

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