Episode 33 is all about Parasaurolophus, a “duck-billed” hadrosaur.

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In this episode, we discuss:

• The dinosaur of the day: Parasaurolophus, whose name means “near crested lizard
• Lived in North America in the Cretaceous
• Fossils found in Alberta, Canada, New Mexico and Utah
• Fossils first found in 1920
• First described in 1922 by William Parks, based on a partial skeleton and skull found in Alberta
• Named after Sir Byron Edmund Walker, chairman of the board of trustees of the Royal Ontario Museum
• Estimated length of 31 feet (9.5 m), weighed 2.5 tons, skull about 5 feet (1.6 m) long
• Both bipedal and quadrupedal
• Probably ran on two legs, but walked on all fours when eating
• Thought to be closely related to Saurolophus (because of similar-ish crest); but now thought to be an offshoot of lambeosaurines, different from Corythosaurus (episode 31)
• Thought to be similar to Saurolophus originally because of its crest (but Saurolophus is part of the sub-family Saurolophus, which had no crests or solid crests) Parasaurolophus’ crest was hollow and is part of lambeosaurine sub-family)
• Three species: Parasaurolophus walkeri (type species), Parasaurolophus tubicen, and Parasaurolophus cyrtocristatus (short-crested)
• P. walkeri has a straight crest and simple tubes; P. tubicen has a long crest with complex tubs; P. cyrtocristatus has smallest, most curved crest
• One specimen of P. walkeri may have had a disease. This is based on a v-shaped gap in the vertebrae, near the base of the neck (though another interpretation is there was a skin flap/ligament to support the head or the fossils were damaged during preparation)
• Charles H. Sternberg found a partial skull in 1921 in the Kirtland Formation in New Mexico; sent to Uppsala, Sweden, and Carl Wiman described the second species, Parasaurolophus tubicen (tubicen comes from the Latin word for “trumpeter”
• In 1995 a second, nearly complete P. tubicen skull was found in New Mexico
• P. tubicen existed slightly later than P. cyrtocristatus in New Mexico, and lived among ornithischians, saurischians, pterosaurs, turtles, and fish
• In 1961 John Ostrom described the third species, P. cyrtocristatus, based on a partial skull with a short crest and most of a skeleton (name comes from Latin curtus “shortened” and cristatus “crested”
• New Mexico at the time of P. cyrtocristatus was swampy, close to the Cretaceous Interior Seaway
• P. cyrtocristatus probably lived among Pentaceratops sternbergii (ceratopsian), pachycephalosaur Stegoceras novomexicanum
• P. tubicen is largest species, P. cyrtocristatus is smallest
• In 2014 PLOS ONE published a study by Xing about another possible species, P. jiayensis (originally Charonosaurus jiayensis, found in China)
• Charonosaurus was named after Charon (boater in Greek mythology who rowed the deceased across the underworld)
• Dinosaurs in the late Cretaceous in North America were very similar to the dinosaurs in Eurasia (Charonosaurus was slightly larger)
• Parasaurolophus had a hollow crest, with tubes that ran from each nostril to the end of the crest (most complex tubes in P. tubicen, and simpler crests in P. walkeri)
• Until the 1960s, scientists thought hadrosaurids were amphibious (and thought the crest helped them stay underwater)
• Now, they think it may have been used for temperature regulation, make low-frequency sounds (to alert others)–Wiman suggested in 1931 when describing P. tubicen since the crest’s internal structure was similar to a swan–also, hardosaurid inner ears are similar to crocodile, so may have been sensitive to high frequencies)
• Scientists used to think the crest was used to either support the head/neck, keep water out of its lungs (back when they thought it was amphibious), used as a snorkel, used as a weapon, used as a branch guard (but it probably ate low-lying plants), stored salt glands (found in marine animals, but doesn’t explain the difference in the crests of the three species), gave a greater sense of smell
• P.E. Wheeler proposed thermoregulation in 1978 (surface area of crest took in heat during the day and dissipated at night)
• In 2009, 17-year-old Kevin Terris, went with paleontologist Andrew Farke on a fossil hunt, and he found “Joe” the baby Parasaurolophus (also the best preserved specimen)
• Parasaurolophus started growing its crest at 25% adult size (sooner than Corythosaurus, which may be why the crests are bigger); also Parasaurolophus grew fast
• Parasaurolophus “Joe” was about one year old, 25% adult sized
• Joe’s skull crest had a little bump, which shows how drastically the shape of the crest changed throughout a Parasaurolophus‘ life
• Joe is named after Joe Augustyn (family sponsored the skeleton preparation)
• Can see Joe on display at the Raymond M. Alf Museum of Paleontology
• See dinosaurjoe.org for a virtual museum about Joe
• In the 1990s, some American paleontologists and computer scientists scanned a Parasaurolophus skull and simulated the sounds it probably made
• Parasaurolophus sounds changed after puberty (younger ones could hear and emit higher frequency sounds)
• Parasaurolophus was a herd animal
• Migrated from shorelines to higher grounds to reproduce
• Pebbly scale prints were found on one Parasaurolophus skeleton
• Narrow beak, so probably choosier about what it ate
• Continually replaced teeth; had hundreds of teeth and a beak to crop plants
• Lived in a warm climate (warmer than Alberta today), no frost, wetter and drier seasons
• Lots of conifers, as well as ferns and angiosperms
• No natural defenses (like Corythosaurus)
• Probably prey to Albertosaurus, Gorgosaurus and Daspletosaurus (easier to hunt than a ceratopsian with horns)
• Other predators may have been Bistahieversor, Teratophoneus, and Troodon (especially to smaller, younger Parasaurolophus)
• But could run on two legs
• Hadrosaurs were the largest land animals that could run on two legs
• Other dinosaurs in North America in the Cretaceous included Albertosaurus, Nanotyrannus, Lambeosaurus, Pachyrhinosaurus
• Parasaurolophus was in Jurassic Park 1, 2, 3 (short appearances, drinking from a lake, in a field, captured by InGen, etc.)
• The Parasaurolophus in Jurassic Park 2 was nicknamed Elvis, because of its pompadour-like horn (and the character Roland Tembo didn’t bother to learn the dinosaur’s name)
• Jack Horner said that the actors of Jurassic Park had a hard time pronouncing Parasaurolophus
• A version of Parasaurolophus appeared in Star Trek Voyager (they were humanoid aliens called “Voths”, descended from Parasaurolophus but fled the galaxy before dinosaurs went extinct)
• Parasaurolophus was also Ducky in Land Before Time
• Hadrosaurid family is known for their crests on their heads (may be used to help recognize individuals, make sounds, or help regulate body temperature)
• Fun Fact: Within an area of about 40 square kilometers, more than 200 oviraptorosaurian nests with eggs have been discovered in the Ganzhou region.