Episode 516: A New Stegosaur with Oddly Formed Toes!. The stegosaur Angustungui has claws just like Scelidosaurus regardless of being over 30 million years newer. Plus a couple of new non-fiction dinosaur books that we’ve been studying currently.
Information:
- There’s a brand new stegosaur, Angustungui qiketaiensis supply
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The dinosaur of the day: Thescelosaurus
- Neornithischian that lived within the Late Cretaceous in what’s now North America
- Neornithischians wore their tooth down inconsistently from chewing and developed sharp ridges, so they might break down powerful plant meals
- One of many final dinosaurs earlier than non-avian dinosaurs went extinct
- Walked on two legs, had a protracted tail, quick arms
- Tail had ossified tendons, so tail wasn’t that versatile
- Had sturdy legs, small, vast palms, had a protracted head with a pointed snout
- Thescelosaurus neglectus is larger than different basal neornithischians, that are about 1 to 2 m lengthy (over 3 to six.5 ft)
- Skeleton is fairly well-known
- Estimated to develop between 8.2 to 13.1 ft (2.5 to 4 m) lengthy
- Closely constructed
- Estimated to weigh about 450 to 660 lb (200 to 300 kg)
- Had a broad rib cage (and due to this fact vast again)
- Had giant, skinny, flat mineralized plates that have been discovered subsequent to the perimeters of the ribs. Unclear what they have been for. Potential they began as cartilage and have become bone because the animal grew up
- Had strong limbs
- Leg bones described as like golf equipment
- In all probability not too quick, based mostly on its heavy construct and legs, the place the higher leg was longer than the shin
- Had 4 toes on its toes
- Had hoof-like toe ideas
- Had 5 fingers on every hand that have been quick and broad
- Had lengthy rod-like bones over the eyes, so regarded prefer it had heavy bony eyebrows
- In all probability herbivorous
- Had a protracted, slender beak
- Had small pointed tooth on the tip of the snout and leaf-shaped cheek tooth
- Had a ridge alongside its higher jaws (the tooth-bearing “cheek” bones) and a ridge on each decrease jaws, which can imply it had muscular cheeks
- In 2022, Michael Hudgins and others studied Thescelosaurus tooth and located they differed in dimension, shapes, ornamentations, denticulation, and put on patterns
- This, together with having a slender beak, could imply Thescelosaurus was a selective feeder
- In all probability browsed near the bottom
- Skeleton often called “Willo” was described in 2000 as having a four-chambered coronary heart and aorta (specimen on show on the North Carolina Museum of Pure Sciences)
- Fossils present in 1993 in South Dakota
- Scientists did CT scans and instructed the center turned to cleaning soap as a result of it was buried in airless circumstances after which fossilized and turned to goethite, an iron mineral. Additionally discovered Thescelosaurus had an elevated metabolic fee (heat blooded)
- Authors instructed the center was just like that of an ostrich with 4 chambers
- A 2001 paper by Timothy Rowe and others discovered the center was a concretion that constructed up an additional dense a part of sedimentary rock
- The specimen was discovered within the Hell Creek Formation in fluvial settings, which don’t normally protect delicate tissues (rivers and streams), and the staff discovered it unlikely a dinosaur coronary heart might fossilize in these circumstances earlier than micro organism consumed it. Additionally mentioned, “Ironstone concretions are infamous for producing suggestive and deceptive shapes” and on this case, the shapes and positions weren’t proper
- Discovered that issues just like the “aorta” lacked arteries coming from it, and argued one other concretion was preserved behind the fitting leg
- Unique authors agreed it was a concretion however mentioned it fashioned round and partially preserved elements of the center
- A 2011 research by Timothy Cleland and others did CT scans, histology, x-rays, and extra and located the article was a concretion of sand from the burial surroundings and never a coronary heart, although there is likely to be remoted areas of tissues preserved
- Discovered that the center didn’t have 4 chambers and as a substitute had three areas that have been unconnected, so couldn’t be a coronary heart (must be linked for blood to stream by)
- Thescelosaurus makes an look in “Dinosaurs: The Remaining Day with Sir David Attenborough”
- Exhibits a Thescelosaurus leg discovered on the Tanis website
- Paul Barrett mentioned the leg has pores and skin impressions that present it was scaly, and that there’s no proof of illness or pathologies or being scavenged (chunk marks) so appears the leg was ripped off rapidly and the dinosaur died virtually immediately
- Potential it died the day the asteroid hit Earth
- Not all paleontologists agree
- Potential that some animals died earlier than the asteroid hit after which acquired ripped aside the day it hit and buried in a approach that makes it appear it died from the asteroid
- Discuss at size in regards to the Finish Cretaceous extinction in our upcoming I Know Paleo mass extinction saga
- In 2014, Clint Boyd described the cranium of Thescelosaurus neglectus
- Cranium not recognized in any respect till Thescelosaurus edmontonensis was synonymized with Thescelosaurus neglectus in 1974 by Peter Galton
- In episode 492, we talked in regards to the research earlier this yr by David Button and Lindsay Zanno, the place they made a 3D mannequin of the within of the mind of Thescelosaurus (the “Willo” specimen) and located it had a strong sense of scent, a delicate vestibular system, however horrible listening to—all which can imply it was a burrower
- Mind was common or beneath common for its physique dimension
- However its olfactory bulbs, which assist with sense of scent, make up about 3% of the endocast quantity (bigger than trendy birds and just like trendy rabbits and pikas)
- Used scent to assist discover meals. Scent would assist it steer clear of predators, and establish its household and younger underground
- Snout might root round in grime
- Had highly effective arms, which can have helped it dig holes
- Had a delicate vestibular system, a comparatively small mind, not nice of listening to, however an amazing sense of scent, which is all good for burrowing
- No preserved burrows, like Oryctodromeus. However possibly spent a while underground and a while above
- For the listening to, most likely couldn’t inform the distinction between high and low frequency sounds very nicely
- Listening to vary just like some crocodilians and squamates (lizards and snakes), however inferior to different dinosaurs like Dysalotosaurus. May most likely hear greatest between ~1100 to 1200 Hz (higher restrict of 3051 Hz). For comparability, Dysalotosaurus estimated to have a listening to vary of ~350 to 3850 Hz
- Kind species is Thescelosaurus neglectus
- Genus identify means “godlike” or “marvelous” or “wondrous” and “lizard”
- Three species: neglectus, garbanii, and assiniboiensis
- Fossils have been present in Alberta (Scollard Formation) and Saskatchewan (Frenchman Formation) in Canada, and in Wyoming (Lance Formation), South Dakota and Montana (Hell Creek Formation) and Colorado (Laramie Formation) within the U.S.
- Fossils first present in 1891 by John Bell Hatcher and William Utterback, in Wyoming (Lance Formation)
- It wasn’t till 1913 Charles Gilmore discovered it within the collections of the Smithsonian and named it Thescelosaurus neglectus (species identify manes “uncared for”)
- Thought it was associated to Camptosaurus on the time
- Charles Gilmore, in 1913 wrote: “the cranium and neck being the one vital elements lacking”
- In 1915 Gilmore wrote a extra detailed description of the fossil, after it was ready
- Through the years, different species assigned to Thescelosaurus however have been later reclassified
- William Morris in 1976 described a specimen with a partial cranium, elements of vertebrae, and finger bones present in South Dakota, U.S. (Hell Creek Formation), as an unidentified species of Thescelosaurus, however Peter Galton later categorized it as Bugenasaura infernalis, which implies “giant cheeked lizard belonging to the decrease areas”
- Morris additionally named one other specimen ?Thescelosaurus garbanii (wasn’t certain it belonged to the genus), based mostly on a partial leg that was a 3rd bigger than different Thescelosaurus specimens, in addition to neck and again bones, present in Montana, U.S. (Hell Creek Formation))
- Found by Harley Garbani
- Estimated to be about 15 ft (4.5 m) lengthy
- In 2009, Clint Boyd and others discovered Bugenasaura to be a synonym of Thescelosaurus (identical skulls), and located Thescelosaurus garbanii to be legitimate. Additionally discovered there was a attainable unnamed third species, based mostly on a specimen with some distinctive options
- In 2011, Caleb Brown and others named the third species, Thescelosaurus assiniboiensis, based mostly on a small, articulated, almost full skeleton present in Saskatchewan (Frenchman Formation)
- Features a cranium, with a braincase
- Species identify refers back to the “District of Assiniboia, a regional administrative unit of the North-West Territories, Canada, from 1882 to 1905”, which finally grew to become Saskatchewan and Alberta. District named after the Assiniboine First Nations Individuals
- Discovered Thescelosaurus was one of the considerable dinosaurs within the Frenchman Formation
- Within the Frenchman Formation, 4 partial skeletons discovered in addition to plenty of remoted bones
- Not a dominant dinosaur within the Hell Creek (one research discovered it was possibly 5% of all articulated skeletons within the Hell Creek Formation), in comparison with about 31% within the Frenchman Formation
- Fossils of the small skeleton discovered within the Frenchman Formation in 1968 and articulated
- Is probably not skeletally mature, however nonetheless thought-about to be a definite species as a result of it’s solely 13% smaller than Thescelosaurus neglectus and it has distinctive options within the cranium that most likely wouldn’t change because it grew up
- Bonebed of a number of dinosaurs discovered within the Frenchman Formation, together with remoted limb bones from small Thescelosaurus, which can be from juveniles
- Some juveniles recognized, largely from tooth
- Many fossils present in sandstones that characterize channel environments
- Appears to have frequented stream channels, and when it died could have been in or close to rivers, which makes it simpler to bury and fossilize
- Lived in coastal plain environments like swamps and marshes
- Might have lived close to streams
- Different dinosaurs that lived across the identical time and place embody the ceratopsids Triceratops and Torosaurus, the hadrosaur Edmontosaurus, the ankylosaur Ankylosaurus, the pachycephalosaur Pachycephalosaurus, and theropods together with Ornithomimus, Troodon, and Tyrannosaurus
Enjoyable Truth:
New know-how means researchers can hunt for fossils already in museum collections.
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