The Big Dinosaur Podcast

Episode 444: Dinosaurs in the Badlands: Featuring 2 Producers from Prehistoric Planet 2. Volcanoes, deserts, and other inhospitable places that dinosaurs lived.

Interview:

Mike Gunton and Tim Walker, Mike Gunton is the Executive Producer and Director of the BBC’s Natural History Unit and Tim Walker is the showrunner and producer of Prehistoric Planet & Prehistoric Planet 2

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The dinosaur of the day: Isisaurus

• Titanosaur that lived in the Late Cretaceous in what is now India and Pakistan (Lameta Formation and Pab Formation, which were about the same age)
• Reconstructions make it look kind of hunched over, with a short neck for a sauropod, with very long legs
• But like other sauropods, in that is fairly large, long tail, walks on four legs, has a proportionally small, elongated skull
• In Prehistoric Planet, pretty stout
• Medium-sized, estimated to be about 59 ft (18 m) long and weighed 15 metric tons
• Humerus was about 58 in (148 cm) long
• In 2009, Sauropod Vertebra Picture of the Week posted that the reconstruction of Isisaurus was “weird as heck”
• Said that there are conflicting reconstructions that are also weird (both reconstructions based on data from the original paper, though one is from the scale bars in the figures in the paper and one is from measurements written in the paper)
• Advocated measuring the skeleton again to determine if the scale bars or the published measurements are accurate
• Wrote: “We know that Isisaurus must have been pretty darn weird because its cervicals are so short”
• Type species is Isisaurus colberti
• Originally thought to be Titanosaurus colberti
• Named Titanosaurus colberti in 1997 by Sohan Lal Jain and Saswati Bandyopadhyay
• Species name in honor of Edwin Colbert “foremost exponent of dinosaurs”
• Sohan Jain and Saswati Bandyopadhyay wrote: “The earliest record of titanosaurids anywhere in the world was established in India in 1877” (Titanosaurus found in the Lameta Formation, which is below the Deccan Traps)
• All fragments found, but enough to name Titanosaurus
• Fossils of Isisaurus collected between 1984 and 1986
• Found a well-preserved, partly articulated skeleton of 65 bones (includes vertebrae, ribs, parts of the shoulder, left arm, pelvis), missing skull, hind limb, and foot bones (possibly due to erosion)
• Because of being articulated, probably buried close to where it died
• Differences in the tail vertebrae from other Titanosaurus species (including more slightly curved surfaces)
• Also differences in the shoulder and arm bones
• In 2003, Jeffrey Wilson and Paul Upchurch renamed it to Isisaurus colberti
• Wilson and Upchurch re-evaluated all Titanosaurus species and found only five to be valid (found the type species “indicus” to be invalid)
• Genus name means “Isi lizard”
• Genus name Isi is in honor of the Indian Statistical Institute “which houses India’s foremost collection of Mesozoic fossil vertebrates and whose scholars discovered and described the holotype skeleton”
• Other sauropods found in what is now India include Titanosaurus (multiple species) and Jainosaurus
• Lived alongside Jainosaurus
• In 2011, Jeffrey Wilson, Paul Barrett, and Matthew Carrano referred a “nearly complete, relatively undeformed braincase” to Isisaurus. Braincase was found in the Pab Formation in Pakistan
• Said there hadn’t yet been any systematic comparison between sauropods found in both the Pab and Lameta Formations, “and there remains a strong possibility that more of the remains collected from the Pab Formation will be referable to Isisaurus and Jainosaurus”
• Also possible there were other titanosaur species
• Said Jainosaurus and Isisaurus don’t seem to be closely related, and that they “represent distinct titanosaur lineages”
• Coprolites thought to come from Isisaurus contained fungus, which are known to infect tree leaves and cause leaf spot and red rot (look how they sound). If those coprolites belong to Isisaurus, means it ate a variety of different tree leaves, and probably was a high browser, like camels and giraffes today
• Based on the fungus, Isisaurus probably lived in a tropical-subtropical climate
• Other dinosaurs found around the same time and place include abelisaurs such as Indosuchus and Rajasaurus
• Other animals that lived around the same time and place include fish, shrimp, gastropods, turtles, crocodiles

Fun Fact:

The Triassic-Jurassic extinction event, one of the largest extinction events in Earth’s history, was likely caused by volcanic eruptions similar to those that formed the Deccan traps.

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Episode 443: Dinosaurs on Islands. Featuring Prehistoric Planet 2. What caused sea level to rise in the Cretaceous and turned Europe into a series of islands? Would Hatzegopteryx be a threat to humans? Which islands did the Prehistoric Planet crew film on? We’ll answer all those questions and more!

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The dinosaur of the day: Morrosaurus

• Ornithopod iguanodont that lived in the Late Cretaceous in what is now Antarctica, at James Ross Island
• Looked somewhat like Iguanodon, but smaller, with longer legs
• Considered to be medium-sized
• Estimated to be up to 13 ft (4 m) long
• Probably was a fast runner
• Type and only species is Morrosaurus antarcticus
• Fossils were found in 2002 by Fernando Novas, who found a partial skeleton in the Snow Hill Island Formation
• Named and described in 2016 by Sebastian Rozadilla and others
• Genus name means “El Morro lizard”
• Genus name refers to El Morro on James Ross Island, where the fossils were found
• Species name refers to Antarctica
• Holotype is part of the right hind leg and part of the foot
• Holotype is at the Museo Argentino of Ciencias Naturales
• Rozadilla and others wrote: “The Cretaceous fossil record of non-avian dinosaurs in Antarctica is strongly patchy and biased”
• Holotype was found about 98 ft (30 m) below a theropod
• Fossils found associated with plesiosaur bones and lots of marine invertebrates
• In 2019, Matthew Lamanna and others described more Morrosaurus material, including more of the foot and associated but unidentified fragments
• The foot material probably belonged to the holotype of Morrosaurus, based on where it was found and that part of the foot was missing with the holotype
• Also mentioned some sort of ornithopod skeleton found near where the Morrosaurus holotype was found. Could be Morrosaurus, but no overlapping bones to compare (ornithopod skeleton doesn’t have the hind limb), so can’t know for sure
• Closely related to Trinisaura, the only other named ornithopod found in Antarctica
• Morrosaurus had a stouter femur and tibia (leg bones), compared to Trinisaura, which was gracile
• Bigger than Trinisaura
• In 2020, Jordi Garcia-Marsa and others did histology on Morrosaurus and Trinisaura
• Found the holotype of Morrosaurus was a sexually mature subadult
• Found the growth pattern of Morrosaurus and Trinisaura was similar to Gasparinisaura and Australian ornithopods
• Found Morrosaurus could grow fast, but it happened periodically, not continuously
• Growth slowed down as it got older
• Past histological studies found that Triassic and Jurassic archosaurs grew in cycles and grew quickly when they were young, which means this is a plesiomorphic feature (ancestral) for archosauriforms, which would have made it possible for dinosaurs to live in extreme environments without needing important physiological changes
• Part of the group Elasmaria, which are known for running fast
• Elasmaria includes dinosaurs from what is now Patagonia, Antarctica, and Australia, which shows they had similar types of animals
• Land connection between Patagonia and Antarctica means there were some shared animals and plants
• Seems that dinosaurs from the James Ross Basin are similar to the dinosaurs found in southern South America
• Similar to lots of Patagonian animals, such as Gasparinisaura, an ornithopod that lived in the Late Cretaceous in what is now Patagonia
• Lived in a seasonal climate, with winters getting down to almost -30° Celsius
• Could get lots of rainfall, and lots of humidity

Fun Fact:

There are a lot of types of islands, but Continental islands are the best places to find dinosaurs.

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Episode 442: Dinosaur instruments in Prehistoric Planet. Anže Rozman and Kara Talve, join from Bleeding Fingers Music. They along with Oscar-winning composer Hans Zimmer created the soundscape for Prehistoric Planet.

News:

• There’s a new pachycephalosaur dinosaur, Platytholus clemensi source
• A new silesaur shows that they weren’t smaller than other dinosauromorphs source

Interview:

Anže Rozman and Kara Talve, two of the composers from the collective at Bleeding Fingers Music. They along with Oscar-winning composer Hans Zimmer recently created the soundscape for Apple TV+ and BBC’s Prehistoric Planet. They won their category in the Hollywood Music in Media Awards and were nominated for other awards as well. They created several instruments for the show including the Fat Rex, Hadro Cello, Triserachord, Raptor Violin, and Petrified Wood Xylyophone (shown below).

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The dinosaur of the day: Zalmoxes

• Rhabdodontid ornithopod that lived in the Late Cretaceous in what is now Romania (Hateg Basin)
• Rhabdodontids were ornithopods that lived in the Late Cretaceous in what is now Europe, when Europe was a chain of islands
• Looked like a typical ornithopod, kind of like Iguanodon but smaller. Walked on two legs, had long arms, a long tail, an elongated skull
• Had a large triangular head and a beak
• Herbivorous, and may have eaten tough plants like horsetails and ferns
• Two species: Zalmoxes robustus and Zalmoxes shqiperorum
• Type species is Zalmoxes robustus
• Zalmoxes subadults found on Hateg Island, that range from 6.6 to 7.9 ft (2 to 2.4 m) long
• Zalmoxes shqiperorum was stockier and larger
• Zalmoxes shqiperorum is larger, with one subadult found that’s 8.2 ft (2.5 m) long
• One juvenile Zalmoxes is 9.5 ft (2.9 m) long
• Because it’s a Hateg dinosaur, has been thought to be a dwarf dinosaur, but not everyone agrees
• In 2009, Zoltan Csiki and others questioned whether the Hateg dinosaurs were really dwarfs
• Did histology on long bones of Zalmoxes specimens
• Found 13 growth marks (LAGs) in a Zalmoxes robustus and 7 in a Zalmoxes shqiperorum, so they weren’t juveniles
• However, also found the specimens were still actively growing when they died, so we haven’t yet found a fully grown Zalmoxes
• Found Zalmoxes had a slow growth rate
• In 2012, Attila Osi and others described a rhabdodontid, the oldest known one by 15 million years, that lived in the Late Cretaceous in what is now Hungary
• Assigned it to Mochlodon vorosi
• Did histology and compared it to Zalmoxes, and this specimen of Mochlodon helps show Zalmoxes was not a dwarf dinosaur
• Found that the ancestral rhabdodontid had a femur lengths of 298–339 mm, which is close in size to the femur of Zalmoxes (which ranged from 320 to 333 mm)
• Both Mochlodon and Zalmoxes lived on islands, however Mochlodon was even smaller
• Mochlodon specimens that are about 3.9 to 5.9 ft (1.2 to 1.8 m) long have features that indicate they are adults. However, late juvenile Zalmoxes specimens are about 6.5 ft (2 m) long
• In 2017, Steve Brusatte and others described a number of new Zalmoxes specimens
• Has been found in multiple areas, or localities, of the Hateg Basin
• Both species lived alongside each other
• More specimens have been found over the years, and Zalmoxes is now one of the most common dinosaurs found on Hateg Island
• About 80% of the skull of Zalmoxes robustus is known
• Most of the skeleton has been found
• At least 22 Zalmoxes individuals have been found in just one locality (up to 25)
• They didn’t necessarily live together, and they were found spread throughout the locality
• Zalmoxes shqiperorum was named based on an incomplete adult specimen and some referred fossils, and then later more fossils were assigned to Zalmoxes shqiperorum. However, Brusatte and others said it was hard to refer fossils to either species because many fossils that were found were disarticulated and/or isolated, so hard to tell where they belonged
• Also, though the species have unique features, it’s hard to compare them to close relatives because we don’t have the same bones of those relatives to compare them to. It’s also unclear if some differences between the species are because of individual variation or ontogeny, and it is possible there’s sexual dimorphism, as Nopcsa had suggested
• Brusatte et al. said a comprehensive revision of Zalmoxes “is becoming increasingly necessary” and that study has begun, so for their paper they accepted that there are two species of Zalmoxes, and referred some specimens to each species
• Described multiple individuals, most were isolated bones
• Described some teeth that were larger than the holotype of Zalmoxes, which “illustrate that Zalmoxes, or at least Z. shqiperorum, could reach a reasonably large size, although still much smaller than the rhabdodontid Rhabdodon priscus from Late Cretaceous faunas in Western Europe”
• In 2022, Felix Augustin and others found two partial braincases previously thought to be Zalmoxes to actually be Telmatosaurus
• To recap, there are two species: Zalmoxes robustus and Zalmoxes shqiperorum
• Zalmoxes now, but first thought to be Mochlodon robustum
• Described in 1899 by Franz Nopcsa (Nopcsa referred to Mochlodon, an ornithopod named by H.G. Seeley, found in Austria),
• Referred to part of the material as Mochlodon suessi and part of it to Mochlodon robustum
• Later, in 1915, said Mochlodon may be the same as Rhabdodon and that the differences were from sexual dimorphism
• Nopcsa compared the fossils with other ornithopods from Europe and North America (Camptosaurus) and found it to be similar to Rhabdodon, found in France
• In 1990 George Olshevsky corrected the name to Rhabdodon robustus
• Named by Weishampel and others in 2003 as Zalmoxes robustus (found enough differences)
• Genus name refers to the Dacian deity Zalmoxis, who retreated in a crypt for three years to be resurrected on the fourth year (similar to how the fossils were liberated)
• Zalmoxes was also a slave of Pythagoras who traveled to Dacia and became a deity
• Species name robustus refers to its robust build
• In 2003, another species named Zalmoxes shqiperorum (for the Albanian name for Albania)

Fun Fact:

Happy world metrology day! (May 20th) If we used the T. rex Sue’s skull to define the length of one “skull” unit, Ankylosaurus would be about 6–7 skulls long & Apatosaurus would be about 15–16 skulls long.

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Episode 441: Ankylosaurs in Antarctica and sauropods in Australia. Plus Brian Curtice joins us to talk about his work on sauropods and other dinosaurs from all over the world.

News:

• New Antarctic osteoderms helps show how nodosaurids survived in such a hostile environment. source
• A Diamantinasaurus skull helps show the connection between titanosaurs on multiple continents source

Interview:

Brian Curtice, a paleontologist who has studied dinosaurs on 6 continents and lectured all over the world. He’s a sauropod specialist and the founder of Fossil Crates, PaleoPortals, and Express Exhibits.

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The dinosaur of the day: Priconodon

• Nodosaurid that lived in the Early Cretaceous in what is now Maryland, U.S. (Arundel Formation and Potomac Group)
• Only really known from teeth, so hard to say what it looked like or how big it was
• However, as a nodosaurid, would have probably walked on four legs, low to the ground, and been covered in armor and have no tail club
• Type species is Priconodon crassus
• Genus name means “saw cone tooth”
• The species name means “thick”
• Named by Marsh in 1888 (Bone Wars dinosaur)
• Marsh named Priconodon on a large tooth. Compared it to Diracodon (now Stegosaurus)
• Tooth had a large root and was worn (described as a “worn tooth”)
• Marsh wrote there were a number of fragmentary remains, which were not found with the tooth (which he named as the holotype specimen) and said these remains would be “described more fully elsewhere”
• Described the tooth as having a “narrow neck, swollen base, and flattened crown” and that “the serrated edges meet above at a sharp angle”
• Lull recognized five more Priconodon teeth, and found them to be similar to Palaeoscincus (a now dubious ankylosaur also named from teeth, found in what is now Montana)
• Lull also referred a vertebral centrum as Priconodon but Gilmore later tentatively assigned it to Ornithomimus and said it was part of the sacrum (connects to the pelvis)
• In 1921 Gilmore wrote that though how we classified armored dinosaurs at that time “is somewhat in confusion”, recent discoveries that had not yet been described show Priconodon should probably be classified as a nodosaurid rather than a stegosaurid, based on the size of its tooth, features, and wear
• In 1978 Walter Coombs also said the tooth belonged to a nodosaur
• Some scientists think it’s dubious, and others agree that it’s valid
• In 1998 Kenneth Carpenter and Jim Kirkland published a review of Early Cretaceous ankylosaurs found in North America, and found Priconodon to be a valid dinosaur and to be a large nodosaurid
• Carpenter and Kirkland found 12 more (isolated) teeth from the same area where the holotype was found, and also tentatively referred a left tibia (shinbone) to Priconodon
• Left tibia came from a coffee mine in Muirkirk, Maryland
• Tibia is stout, like other nodosaurids, and is about 12 in (31 cm) long
• Carpenter and Kirkland wrote “we find it peculiar that no armor plates have yet been reported from the Arundel Formation”. However, they said that doesn’t mean Priconodon didn’t have armor. “Instead, we advocate that either we are mistaken and Priconodon is not an ankylosaur, or that it is simply fortuitous that armor has not yet been found. This should not be surprising, considering how few fossils have been found in the Arundel.”
• In 2004, Alex West and Neil Tibert found Priconodon to be valid, by comparing its teeth to other nodosaurs and ankylosaurs
• Teeth are different from other nodosaurid teeth because they are so large
• Tooth size ranges from about 0.4 to 0.6 in (1 to 1.5 cm) long and about 0.3 to 0.55 in (0.7 to 1.4) cm tall, according to Carpenter and Kirkland
• For comparison, the largest Edmontonia teeth were about 0.45 in (1.19 cm) long and about 0.4 in (1.5 cm) tall
• Other animals that lived around the same time and place included pterosaurs, sharks, lungfish, turtles, and crocodilians, and dinosaurs including carcharodontosaurids, dromaeosaurs, ornithischians, ceratopsians (most known from fragments and teeth and considered to be indeterminate members of their groups—so not too specific)

Fun Fact:

Ankylosaur heads are one of the most complex armored body parts in the animal kingdom.

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

Episode 440: Fossilized ankylosaur larynx, sinus infections, and facial bite marks. Plus Trinity the T. rex was auctioned, a brief history of dinosaur jewelry, and dinosaur of the day Saurolophus

News:

• A fossilized larynx of an ankylosaur, Pinacosaurus, shows that they didn’t use their larynx to vocalize source
• Researchers found a surprising massive bony growth near the trachea of a Tarchia that was likely caused by an infection source
• Trinity the T. rex was auctioned for $6.1 million (USD) source
• Fukui Prefectural University in Japan will be offering dinosaur studies source
• There’s a family friendly dinosaur movie, The Adventures of Jurassic Pet 2: The Lost Secret source

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The dinosaur of the day: Saurolophus

• Hadrosaurid that lived in the Late Cretaceous in what is now Alberta, Canada and Mongolia (Horseshoe Canyon Formation and Nemegt Formation)
• One of the few dinosaurs known from more than one continent
• Looks similar to Parasaurolophus, with the bulky body, could walk on all fours, had a long, horse-shaped head, and long tail, but the crest was different
• Crest was smaller, spike-like, and curved upwards at the back
• Crest goes up and back at about a 45 degree angle, and sticks out behind the skull
• Crest is mostly solid, but had a hollow base (where it attached to the skull)
• Crest is made of its nasal bones
• Longest skull bones are the nasal bones
• Crest grew as it aged
• Based on its scleral rings, Saurolophus may have been cathemeral (active throughout the day for short periods of time)
• Herbivorous, and could walk on all fours or on two legs
• Had a horseshoe-shaped lower jaw that wrapped around the toothless parts of the jaw to form a beak
• Cropped plants with its beak
• Had dental batteries with hundreds of teeth, which it constantly replaced
• Could grind its food, almost like chewing
• Could eat food that was up to 13 ft (4 m) above the ground
• Type species is Saurolophus osborni
• Genus name means “lizard crest”
• Named by Barnum Brown in 1912
• Second species is Saurolophus angustirostris
• Described by Anatoly Rozhdestvensky in 1952
• Brown found the Saurolophus osborni fossils in 1911
• First nearly complete dinosaur skeleton found in Canada
• Three Saurolophus osborni specimens have been found, including a virtually complete skull and skeleton
• Holotype of Saurolophus osborni was mounted on a panel behind glass, and shows the right side of the animal, at the AMNH
• The Russian Palaeontological Expedition to the Gobi Desert in 1947, led by I. A. Efremov, found a hadrosaur bonebed (later found to be Saurolophus angustirostris)
• Bonebed is known as “Dragon’s Tomb”
• So many well-preserved and articulated skeletons in Dragon’s Tomb, which has made it a favorite spot for poachers
• Saurolophus is about 20% of the fossils found in the Nemegt Formation
• At least 15 specimens known for Saurolophus angustirostris
• In 1930 Riabinin named Saurolophus kryschtofovici, but it’s no longer considered to be valid (based on part of a hip found from Heilongjiang Province, China but it’s too fragmentary, and it had been compared to an isolated but complete ischium that was later found to be Hypacrosaurus)
• In 2013, Albert Prieto-Márquez and Jonathan R. Wagner named Saurolophus morrisi, but that’s now considered to be Augustynolophus, the state dinosaur of California
• Brown thought Saurolophus and Trachodon were similar and related. Also compared the crest to that of a chameleon’s (thought it would be a spot where muscles attached and then connected to a frill in the back of the head like a basilisk lizard)
• Brown said the crest is “the most characteristic and striking feature of the skull”
• Peter Dodson thought the crest was used for identifying if the animal was male or female
• In 1981, Maryanska and Osmólska suggested the crest was used for thermoregulation
• James Hopson thought the crest was for display and suggested there were inflatable skin flaps over the nostrils as well
• Now there are just the two valid species: osborni and angustirostris
• Both species have the same head crests, and lots of other similarities, so in the past scientists questioned if both species were valid
• In 2011, Phil Bell redescribed both Saurolophus angustirostris and Saurolophus osborni (in two different papers)
• Found the two species to be distinct and valid, and each had unique characters (not just due to individual variation)
• Saurolophus osborni was estimated to be about 27 to 28 ft (8.2 to 8.5 m) long and weigh about 3 tonnes, with a skull about 3.3 ft (1 m) long
• Saurolophus angustirostris is estimated to be up to 43 ft (13 m) long, and possibly even bigger, and weigh up to 11 tonnes
• Saurolophus angustirostris had a 20% longer skull, and the front of its snout went more upward than Saurolophus osborni
• Largest known Saurolophus angustirostris skull is about 4 ft (1.22 m) long
• Found differences in the details of the skull too
• Unclear which species came first
• In 2012 Phil Bell studied the skin impressions of both species, which were found on multiple individuals
• Skin from the face of Saurolophus osborni known from a single fragment from a right dentary
• No skin found on S. osborni forelimb, but “entire forelimb of S. angustirostris covered in a uniform arrangement of 1–2 mm wide pebbles even in relatively large individuals”
• Skin found in pelvic region of S. angustirostris (small patch on a subadult)
• Skin found on part of the foot of S. osborni
• Skin on hindlimb of S. angustirostris also found in adults and subadults
• At least two patches of faintly preserved skin found on a juvenile Saurolophus angustirostris
• Patches of miscellaneous skin also found (unclear where on the body they came from)
• Found lots of scales, including: polygonal (range from four to six-sided), pebbly scales that are small and rounded, shell scales that are asymmetrical and somewhat trapezoidal in shape, and irregular scales (no obvious geometrical sides), shield scales that are circular and are typically flat or domed
• Found differences in the patterns and shapes of the scales, enough to differentiate the two species
• Skin found on the tails of both species
• Lots of differences in the tail scales
• On Saurolophus osborni, the tail scales were more clustered and it may have had more of a spotted coloration
• Saurolophus angustirostris had scales on its tail that made vertical patterns, which may mean it had striped colors on its tail
• In 2018, Phil Bell and others studied the sedimentology and taphonomy of Dragon’s Tomb
• Ivan A. Efremov’s team found seven hadrosaurid skeletons lying close together (discovered in 1948 by V. Pronin)
• Collected at least four skeletons, or parts of four skeletons, and had to transport them by camel (couldn’t get vehicles to the site)
• Lots of expeditions have also visited the site
• Dragon’s Tomb has a bonebed of mostly Saurolophus angustirostris, with juveniles, subadults, and adults
• One tyrannosaur skeleton found, probably Tarbosaurus
• Found the bonebed was at least about 21,500 sq ft or 2000 sq m, and there may be over 100 Saurolophus skeletons in the bonebed
• Estimated the minimum number of Saurolophus individuals in the bonebed is 21
• Shows gregarious, or social, behavior of Saurolophus angustirostris
• Evidence of a catastrophic mass death (they were killed and buried rapidly)
• Based on the skeletons being well preserved and complete, likely bonebed happened because of a flood, or multiple floods that happened quickly (days to weeks in one year)
• One left arm of a nearly complete Saurolophus angustirostris had heavy damage from bite marks. The rest of the skeleton was fine, so it’s likely a tyrannosaurid scavenged the arm, probably Tarbosaurus
• “Unfortunately, the reliability of this locality for yielding beautiful and complete specimens of Saurolophus angustirostris has made it a target of illegal fossil poachers, and in recent years untold numbers of specimens have been illegally plundered and/or destroyed”
• Poaching started sometime after 2001
• In 2015 Leonard Dewaele and others described a small, partial nest of Saurolophus angustirostris, that probably came from the Dragon’s Tomb in the Nemegt Formation
• Unclear where exactly the fossils came from. Fossils were poached then ended up in Japan by way of a collector from Europe, then donated to the Royal Belgian Institute of Natural Sciences, which repatriated the fossils to Mongolia. They’re now at the Institute of Paleontology and Geology of the Mongolian Academy of Sciences
• Said there were three, maybe four, babies and two fragmentary eggshells in the block they prepared
• Babies were considered to be perinates (just born) because the length of their skulls were less than 5% the length of the adult skulls
• Skull length estimated to be about 2.3 in (6 cm) long
• No nasal crest, may have broken off or possible baby Saurolophus didn’t have a crest (yet)
• But, adult crests are so robust it’s unlikely the crest broke off
• Other skull bones were similar to those in adult Saurolophus (how they knew the babies were Saurolophus)
• Had upwardly directed snouts like adult Saurolophus
• Eggshell fragments found look similar to other eggs associated with more basal hadrosauroids
• Arm bones found from three, maybe four, individuals
• Babies were probably close to each other and nest-bound when they died
• Unclear if the babies had just hatched or were still in the eggs when they died, but they were dead and partly decomposed when they were buried by river sediment
• A partially articulated skeleton (includes the skull, neck vertebrae, part of the tail, the right leg, and more) and the rest of the bones being disarticulated suggests some of the perinates were more decomposed than others
• Studied the sediments surrounding the fossils
• They were buried by river sediment probably during the wet summer season
• Probably died within a relatively short time interval
• Fragile bones are well preserved and a partially articulated skull show the bones weren’t moved far before being buried
• Babies didn’t have the spike-like crest, which probably means the crest grew as Saurolophus grew up
• Also as it grew, its snout grew proportionally longer
• Ducky from Land Before Time is probably a Saurolophus, though there’s some debate around this
• In the 1997 Land Before Time Sing Along Songs video, Ducky is a Saurolophus
• Ducky had a head crest like Saurolophus
• But Ducky was portrayed inconsistently in the series. Apparently the Land Before Time website, which no longer exists, called Ducky both Trachodon and Parasaurolophus, and in merch Ducky is labeled as Parasaurolophus
• In the Horseshoe Canyon Formation, other dinosaurs that lived around the same time and place as Saurolophus included the ornithopods Hypacrosaurus and Parksosaurus, the ankylosaur Anodontosaurus, the pachycephalosaur Sphaerotholus, the ornithomimid Ornithomimus, the theropods Atrociraptor and Albertonykus, and the larger theropod tyrannosaurid Albertosaurus
• In the Nemegt Formation, there were streams and rivers and shallow lakes. Other dinosaurs that lived around the same time and place as Saurolophus included the hadrosaurid Barsboldia, the pachycephalosaurs Homalocephale and Prenocephale, the ankylosaur Saichania, the titanosaurs Nemegtosaurus and Opisthocoelicaudia, the alvarezsaur Mononykus, troodontids such as Zanabazar, oviraptorosaurs including Rinchenia and Nemegtomaia, ornithomimosaurs Anserimimus and Gallimimus, theropods Deinocheirus and Therizinosaurus, and the larger theropod tyrannosaurid Tarbosaurus

Fun Fact:

Birds can recover very fast from near extinction.

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