Episode 338 is all about Cetiosaurus, the first sauropod to be described, although it was originally thought to be a whale or large crocodile.
We also interview Mariana Di Giacomo, paleontologist and Natural History Conservator at the Yale Peabody Museum where she is overseeing the massive expansion of the museum. You can follow here work on Instagram @marudigi, twitter @marianadgiacomo, or on marianadigiacomo.com
Big thanks to all our 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 https://www.patreon.com/iknowdino.
You can listen to our free podcast, with all our episodes, on Apple Podcasts at: https://itunes.apple.com/us/podcast/i-know-dino/id960976813?mt=2
In this episode, we discuss:
News:
- The oldest centrosaurine ceratopsian, Menefeeceratops, was described from northwestern New Mexico source
- In Lufeng, Yunnan Province in China, researchers recently found the skeleton of a three year old sauropodomorph dinosaur source
- Headless Henry the Triceratops is being 3D printed for a display planned for June at the Missouri Institute of Natural Science source
- There is a new, 100% virtual Museum of the Patagonian Desert of Añelo source
- The dinosaur mascot Arky the Acrocanthosaurus at the Witte Museum in San Antonio, TX recently got “vaccinated” source
- In Kalamazoo, Western Michigan University has a free dinosaur park on campus source
- Fairchild Tropical Botanic Garden in Coral Gables, Florida has a new exhibit, Jurassic Garden: A Prehistoric Adventure source
- In Champlin, Minnesota there’s a Sinclair gas station known for its Dino the Dinosaur that has over 100 different costumes source
- K-pop group NCT Dream and the people who made the kids song Baby Shark made a dinosaur song called Dinosaurs A to Z source
- The show Rugrats is getting a reboot and the trailer features a T. rex chasing them Jurassic Park style source
The dinosaur of the day: Cetiosaurus
- Sauropod that lived in the Middle Jurassic in what is now Europe (England, France, Switzerland, Morocco, though some of those specimens have been reassigned to different genera)
- Not the same as Cetiosauriscus, another sauropod that lived in the Middle Jurassic in what is now England
- Look like other sauropods. Quadrupedal, with a long neck and small head
- Cetiosaurus oxoniensis (the type species as of 2014) is estimated to be 52 ft (16 m) long and weigh 11 tonnes
- Had a shorter tail and neck than most sauropods
- Tail had at least 40 caudal vertebrae
- Had relatively long forelimbs
- Forelimb was about the same length as the hindlimb
- Dorsal vertebrae (back) were heavy, not hollow like other sauropods such as Brachiosaurus
- Herbivorous
- Based on its neck length and limb proportions, probably was a generalist feeder, eating vegetation at low and medium-high levels
- Lived in an area with floodplains and open woodland
- Wastebasket taxon, with 18 species named. Only one considered to be a valid Cetiosaurus today: Cetiosaurus oxoniensis
- Cetiosaurus oxoniensis became the type species in 2014, and is based on multiple specimens (includes most bones, but not much of the skull, possibly a braincase)
- Genus name means “whale lizard”
- Described in 1841 by Richard Owen, who originally thought it was a large marine animal (whale or crocodile); named just before he coined the term Dinosauria
- Species name “Oxoniensis” refers to Oxford
- John Kingdon reported the first fossils, found in Chipping Norton, England, in a letter read in 1825 to the Geological Society, then Owen named the animal
- Cetiosaurus first described based on caudal vertebrae, limb elements, and a partial shoulder girdle
- Mostly knew back then that it was a giant. Richard Owen said its bones were much bigger than an elephant’s or Megalosaurus, and only Iguanodon and whales were similar in size
- 1842 in the Proceedings of the Geological Society of London: “As there is no known extinct saurian which can so nearly compete in size with the Cetiosaurus as the Iguanodon, it is fortunate, Prof. Owen observes, that the distinguishing characters are so well marked and easily recognizable”
- Richard Owen thought the limb bones were like crocodiles and the vertebrae like whales
- Richard Owen also thought it was carnivorous
- Mark Witton has a fun whale like version of Cetiosaurus (long tail, big middle, strong jaws), based on Richard Owen’s description
- Later, Owen classified Cetiosaurus as a crocodilian
- Owen also named two additional species in 1842: Cetiosaurus hypoolithicus and Cetiosaurus epioolithicus, based on fossils found in Yorkshire
- Then that same year he named four more species: Cetiosaurus brevis “the short one”, Cetiosaurus brachyurus “the short-tailed”, Cetiosaurus medius “the medium-sized”, and Cetiosaurus longus “the long one”
- When naming the four new ones, he used the fossils from Cetiosaurus hypoolithicus and Cetiosaurus epioolithicus (so stopped using those two name)
- In 1849, found that some of those fossils were from Iguanodontidae
- So Alexander Melville in 1849 named the fossils that were from sauropods (from Cetiosaurus brevis) as Cetiosaurus conybeari, but that just made conybeari a junior synonym of brevis
- Owen thought Cetiosaurus was a crocodile as late as 1859
- Right femur of Cetiosaurus oxoniensis found in 1868 by workers, and Professor John Phillips excavated from 1869 to 1870 and found three skeletons
- Thomas Huxley said Cetiosaurus was a dinosaur in 1869
- Phillips named two species in 1871: Cetiosaurus oxoniensis and Cetiosaurus glyptonensis
- In 1871, John Phillips suggested Cetiosaurus was an herbivorous dinosaur, in a monograph
- In 1875 Richard Owen said Cetiosaurus was a large, aquatic dinosaur
- In 1968, a new Cetiosaurus oxoniensis specimen was found, called the “Rutland Dinosaur”
- Found by someone driving an excavation vehicle, found at the base of the Rutland Formation in England
- The Rutland Dinosaur is the most complete sauropod found in the UK
- About 40% complete, and includes most of the cervical bones, most of the dorsal vertebrae, part of the sacrum and anterior caudals, chevrons, ilium, right femur, and rib and limb fragments
- Most complete sauropod found in England
- Rutland Dinosaur is about 49 ft (15 m) long, and since 1985 has been on display in the Leicester Museum & Art Gallery
- Wastebasket taxon. Thirteen species of Cetiosaurus have been named on fossils found in England, three from France, one from Morocco, one from Switzerland
- Richard Owen initially named Cetiosaurus without any species name
- Cetiosaurus medius was traditionally considered to be the type species of Cetiosaurus. Richard Owen said so in an 1842 article
- Richard Lydekker assigned Cetiosaurus oxoniensis as the type species in 1888, but by modern rules of the ICZN the original author (Richard Owen) is the one who should select the type species
- In 2003 and 2009, Paul Upchurch and John Martin looked through all the species of Cetiosaurus and found most of them to be invalid
- Lots of species based on fragmentary material
- Found some of the species to be valid dinosaurs, but different types of dinosaurs
- 1905, On Parts of the Skeleton Cetiosaurus leedsi paper: New specimen found near Petersborough. “This specimen is so well preserved that, since its acquisition by the British Museum, it has been possible to mount the various bones on ironwork in their natural position.”
- About a chain of 10 small vertebrae: “A chain of such vertebrae at the end of so massive an animal as Cetiosaurus must have been especially liable to accident”
- However, in 2003 Paul Upchurch and John Martin found that there were no autapomorphic features of the leedsi species, and said Cetiosaurus leedsi was a nomen dubium
- Upchurch and Martin proposed to the ICZN to change the type species from Cetiosaurus medius (they found medius to be invalid, due to fossils being not distinct enough) to Cetiosaurus oxoniensis
- Upchurch and Martin found five autapomorphies of Cetiosaurus oxoniensis, including having “pyramid” shaped neural spines in the dorsal vertebrae
- The ICZN accepted the proposal in 2014
- Upchurch and Martin proposed the Rutland Dinosaur to be the lectotype
- Scientists have suggested Cetiosaurus to be closely related to neosauropods, so Cetiosaurus may help show the origins of neosauropods
- Can see Cetiosaurus statue at Edaville Family Theme Park in Massachusetts
- Cetiosaurus fossils in the collections at The Museum of Gloucester
Fun Fact: Non-avian dinosaurs roamed Earth for almost one full galactic year (a full revolution of our solar system around the center of the galaxy).
Sponsors:
This episode is brought to you in part by BetterHelp which offers professional counseling done securely online. You can get 10% off your first month by visiting betterhelp.com/ikd
