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Episode 345: Treason Day Turkey


    Episode 345 is all about Hypacrosaurus, a crested hadrosaurid identified from a number of nests, together with embryos.

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    On this episode, we focus on:


    • A brand new hadrosauroid from Spain, Magnamanus, was found with a novel gap in its jaw supply
    • The Carnegie Museum of Pure Historical past in Pennsylvania prolonged their Dinosaur Armor exhibit till July 31 supply
    • In Saratoga Springs, New York, Common Preservation Corridor is getting Dinosaurs in Movement from July 25 to Oct 15 supply
    • The Mall of America has 50 animatronic dinosaurs in its car parking zone till July 11 supply
    • In Louisville, Kentucky, Louisville Zoo has an exhibit known as Dino Quest, from now till Sept 19 supply
    • The 9 yr previous who’s preventing most cancers and needed to go to Dinosaur Nationwide Monument simply completed her 14 day highway journey supply
    • Bandai Spirits, is making fashions of dinosaur fossils with a limestone-based plastic which they declare is extra sustainable supply
    • The lady who owns the Flintstone home settled the lawsuit with Hillsborough, CA to maintain her statues & sculptures supply
    • Digital displays and collections have grown in the course of the pandemic supply
    • A brand new mashup music video consists of Stroll the Dinosaur and scenes from the TV present Dinosaurs supply
    • Ark: Survival Developed has inflatable T. rex costumes in its summer-themed occasion till July 14 supply
    • A brand new picture from Jurassic World: Dominion exhibits among the “sensible fashions” used within the movie supply

    The dinosaur of the day: Hypacrosaurus

    • Lambeosaurine hadrosaurid that lived within the Late Cretaceous in what’s now Alberta, Canada and Montana, US
    • Appears like Corythosaurus, and had a tall, hole rounded crest (not fairly as tall)
    • Closest family Corythosaurus and Olorotitan
    • Estimated to be 30 ft (9.1 m) lengthy and weigh 4.4 tons
    • Had a rounded, hole crest on prime of its head (generally described as a helmet crest)
    • Crest may very well be for show in figuring out species, and will make sounds
    • Had tall neural spines, which made it appear to be it had a tall again
    • Bipedal and quadrupedal
    • Had a broad beak
    • Had dental batteries with lots of of enamel, and always changed its enamel
    • Floor its meals in a approach that resembles chewing (held meals in jaws with a cheek-like organ)
    • May eat meals on the bottom and as much as 13 ft (4 m) above the bottom
    • Endothermic, based mostly on a examine by Reese Barrick and others in 1996 that discovered the oxygen-isotope ratio present in its bones (not a lot variation within the ratio within the bones, so had an analogous physique temperature in its entire physique)
    • John Ruben and others in 1996 discovered that Hypacrosaurus had decrease metabolic charges in comparison with fashionable birds and mammals
    • Sort species is Hypacrosaurus altispinus
    • Holotype present in 1910 by Barnum Brown, and consists of vertebrae, neural spines, a number of ribs, ilia, partial proper pubis, proper ischium (Horseshoe Canyon Formation); no cranium discovered on the time
    • Brown described the fossils in 1913, and stated they had been a brand new genus, much like Saurolophus
    • Genus title means “close to the very best lizard”
    • Named as a result of it was nearly as giant as T. rex (one of many earlier named dinosaurs, so was one of many largest ones identified on the time)
    • Barnum Brown wrote: “It’s largest of all identified Trachodonts, approaching in measurement the nice carnivorous dinosaur Tyrannosaurus of the later Lance formation.”
    • Species title altispinus means “excessive spines” (had among the tallest spines of hadrosaurs)
    • Different specimens described after, and named as new genera and species. Contains Cheneosaurus tolmanensis (named by Lawrence Lambe in 1917), based mostly on a cranium, limb bones, vertebrae, and pelvic bones (present in Horseshoe Canyon Formation), and Procheneosaurus (named by Richard Swann Lull and Nelda Wright, and located within the Two Medication Formation)
    • Peter Dodson within the Seventies instructed these genera had been most likely juveniles of different lambeosaurines, and thought Cheneosaurus was juvenile Hypacrosaurus altispinus
    • Procheneosaurus regarded completely different, and later discovered to be Hypacrosaurus stebingeri (which wasn’t named till 1994)
    • Hypacrosaurus stebingeri named based mostly on embryos and hatchlings discovered close to nests within the Two Medication Formation, “the biggest assortment of child skeletal materials of any single species of hadrosaur identified”
    • Jack Horner and Phil Currie wrote concerning the nesting floor discovered of Hypacrosaurus, and named them Hypacrosaurus stebingeri
    • Talked about three nesting horizons, one in Alberta, two in Montana, had many eggs and infants starting from embryos to giant nestlings (juveniles and adults additionally widespread)
    • Species title in honor of the late Eugene Stebinger, who first described the Two Medication Formation and found the primary stays of this species
    • Uncommon in that it has no autapomorphies, however phylogenetically in between; stated it was an intermediate taxon between species of Lambeosaurus and Hypacrosaurus altispinus (however shares extra traits with Hypacrosaurus than Lambeosaurus)
    • Worn enamel of embryos present they floor their enamel within the eggs, and enamel had been practical upon hatching
    • Ontogenetic modifications embody improve in rows of enamel, growth of the nasal crest, modifications in proportion of the orbits to cranium measurement, and different modifications
    • David Evans in 2010 in contrast skulls and regarded on the systematics of Hypacrosaurus altispinus
    • Checked out 15 skulls
    • Discovered that the crest grew bigger because it aged
    • Nasal passage had an s-loop, with the decrease half extending to the cranium roof stage
    • Plenty of Hypacrosaurus specimens starting from embryos to adults
    • Gregory Erickson and others determined to have a look at Hypacrosaurus and Protoceratops embryos in 2016
    • Used CT scans and located Hypacrosaurus incubated in 171 days, for much longer than anticipated
    • Primarily based on traces of development within the embryo enamel
    • Each day development traces known as von Ebner traces, that are fashioned when the enamel varieties on embryo enamel. Liquid dentin (layer underneath the enamel) fills contained in the tooth and mineralizes each evening. As soon as the tooth is totally stuffed in, the traces cease forming
    • von Ebner traces used to seek out tooth-formation and incubation instances in alligators, people, and different mammals earlier than
    • Lengthy incubation instances not good throughout extinction occasion
    • Younger and embryonic specimens had deep skulls and a slight enlargement within the bones (that may flip right into a crest)
    • Hypacrosaurus egg was about 8.8 lb (4 kg) (Ostrich eggs are slightly over 1 kg)
    • Lisa Cooper and others studied a Hypacrosaurus specimen in 2008 and checked out LAGs (specimen considered about 13 years previous)
    • Reproductively mature by age 2 or 3 (so can reproduce rapidly, an indication of being a prey animal)
    • Grew sooner than tyrannosaurids (which preyed upon it; tooth marks present in a fibula), so might get giant sufficient rapidly to defend itself
    • Could have reached full measurement at age 10 or 12, in comparison with tyrannosaurs that take 20 to 30 years (based mostly on development rings in leg bones)
    • Alida Bailleul and others in 2020 discovered cartilage traces on a hatchling cranium of Hypacrosaurus stebingeri
    • Remoted some cells to check with DNA staining. Examined constructive to potential chemical markers of DNA, in a approach much like emu cells (they dyed residing emu cells and in contrast the 2)
    • Didn’t assume it was fossil contamination, which can imply DNA lasts longer than beforehand thought
    • Used two sorts of stains, one which connected to DNA fragments and useless cells, and one which connected to any DNA. They had been binding to particular molecules and never the entire cell, which is why the staff didn’t assume there was bacterial contamination
    • Cells got here from cartilage within the cranium of a child Hypacrosaurus
    • Discovered cells that seemed to be frozen and within the technique of dividing, cells with nuclei, and one cell that appears to comprise one thing that resembles chromosomes
    • Buildings inside sure tissues had been in line with cartilage cells, and so they had inside buildings that resembled nuclei and chromosomes
    • Items too brief to learn to verify whether it is DNA
    • Helps concept that some fragmentary DNA could stay within the cells
    • Wants extra analysis, but when upheld, it means biochemical traces of animals might stick round tens of tens of millions of years longer than beforehand thought
    • However, could also be too troublesome to inform when the traces of DNA come from a dinosaur, or they simply appear to be they arrive from a dinosaur, however it’s DNA traces of one thing else, like micro organism and different microorganisms (as Renxing Liang and others discovered on a Centrosaurus)
    • Nonetheless early days, want extra analysis (numerous unknowns) and possibly extra standardized processes (staff examined Hypacrosaurus with DNA staining, and the Centrosaurus staff used DNA sequencing); additionally the flexibility to copy
    • Different dinosaurs that lived in the identical time and place as Hypacrosaurus altispinus (Horseshoe Canyon Formation) included hadrosaurids Edmontosaurus and Saurolophus, hypsilophodont Parksosaurus, ankylosaurid Anodontosaurus, nodosaurid Edmontonia, ceratopsians Montanoceratops, Anchiceratops, Arrhinoceratops, and Pachyrhinosaurus, pachycephalosaurid Stegoceras, ornithomimosaurs Ornithomimus and Struthiomimus, tyrannosaurs Albertosaurus and Daspletosaurus, and troodontids and dromaeosaurids
    • Different dinosaurs that lived in the identical time and place as Hypacrosaurus stebingeri (Two Medication Formation) embody the hadrosaurs Maiasaura and Prosaurolophus, troodontid Troodon, tyrannosaurid Daspletosaurus, caenagnathid Chirostenotes, dromaeosaurids Bambiraptor and Saurornitholestes, ankylosaurs Edmontonia, Oohkotokia, and Scolosaurus, hypsilophodont Orodromeus, and ceratopsians Achelousaurus, Brachyceratops, Einiosaurus, and Rubeosaurus. Space was additional away from the Western Inside Seaway, so greater and drier than Horseshoe Canyon Formation

    Enjoyable Truth:
    The US has a nationwide dinosaur (the bald eagle). Though they don’t eat individuals, they do generally eat raccoons & seal pups.


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