Episode 54 is all about Becklespinax, a dinosaur recognized from three excessive spines.
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On this episode, we talk about:
- The dinosaur of the day: Becklespinax
- Title means Beckle’s backbone
- Lived within the early Cretaceous, in what’s now England
- Samuel Beckles, a fossil collector, discovered the primary bones close to East Sussex within the early 1850s
- He despatched the bones to Richard Owen, who wrote about them in 1856. He categorized it as Megalosaurus bucklandii (wastebasket taxon) Owen had Joseph Dinkel make a lithography, primarily based on three again vertebrae with tall spines. This picture appeared in an 1884 version of 1855 quantity of labor on British fossils, which led some folks to suppose the fossils had been discovered round 1884 (as a substitute of the 1850s).
- Owen thought the again vertebrae was a part of the shoulder, and it’s thought he knew about these bones again in 1853 when he instructed Benjamin Waterhouse Hawkins to offer the life-sized Megalosaurus sculpture in Crystal Palace Park a hump on its again.
- Since Becklespinax was found very early (when paleontologists first began discovering dinosaurs), that’s why Owen assigned it to Megalosaurus and thought that primarily based on one specimen Megalosaurus had a hump
- Richard Lydekker reclassified the vertebrae as a part of Megalosaurus dunkeri in 1888 (a dinosaur from the Cretaceous named primarily based on a tooth from Germany); Friedrich von Huene named a separate genus for Megalosaurus dunkeri in 1923, Altispinax (title means “excessive spines”). Megalosaurus dunkeri grew to become Altispinax dunkeri, and the title was first utilized in 1939 by Oskar Kuhn
- However the tooth Altispinax was primarily based on was undiagnostic, so Altispinax grew to become a nomen dubium (and it was unclear the vertebrae had been associated to the tooth)
- So, in 1988 Gregory Paul renamed it Acrocanthosaurus? (sure he added a query mark) altispinax (with the species title the identical because the outdated genus title to indicate they each referred to the vertebrae).
- Gregory Paul renamed Altispinax as Acrocanthosaurus primarily based on the truth that Acrocanthosaurus had excessive neural spines and in addition lived within the early Cretaceous
- However Gregory Paul wasn’t certain about this classification (query mark). Due to this, in 1991 George Olshevsky gave it a brand new genus title in honor of Beckles, and it grew to become Becklespinax altispinax.
- Different names resembling Altispinax altispinax and Altispinax lyderkkerhueneorum are junior synonyms (referring to the identical again vertebrae materials)
- George Olshevsky mentioned the fossils had been sinraptorid (allosauroid theropods just like Sinraptor) and that’s why he renamed it Becklespinax
- Gregory Paul estimated that Becklespinax weighed about 1 ton and was shorter than Acrocanthosaurus atokensis (which he estimated was 26 ft or 8 m lengthy)
- The three again vertebrae have about 14 in (35 cm) excessive neural spines. Ralph Molnar mentioned the 2 spines closest to the cranium had been fused (the closest backbone is about 2/3 the peak of the opposite 2 spines, and appears damaged off, and the 2nd backbone partly overgrows this hole; so Becklespinax most likely had an harm and the wound closed from behind)
- However in 2003, Darren Naishgave mentioned this hole was pure. He mentioned Richard Owen had written about massive depressions on the backbone sides and mentioned they had been from pneumatisation (air cavities in tissue), which was the primary time this was seen in a dinosaur (though in 2006 it was discovered that Christian Erich Hermann von Meyer had truly discovered this earlier, in 1837, with Saurischia on the whole)
- In 2010 a Concavenator again crest with solely two excessive vertebrae confirmed that Becklespinax’s backbone could also be full
- As a result of solely three spines had been discovered for Becklespinax, it’s onerous to know precisely how the dinosaur regarded (although there are theropods resembling Acrocanthosaurus and Spinosaurus with excessive spines, however then Concavenator had a small hump with simply two vertebrae
- Additionally Metriacanthosaurus, from the Jurassic in England, was a theropod with massive neural spines
- Concavenator is a cousin of Acrocanthosaurus (Concavenator present in Spain)
- No higher, extra full specimens discovered but of Becklespinax, so onerous to know for certain what it regarded like
- Nevertheless it resembles Concavenator, so most likely additionally a carcharodontosaur with a sail again
- Although Concavenator and Becklespinax lived 10 million years aside, Naish has recommended the likelihood they’re the identical genus (Concavenator corcovatus could also be Becklespinax corcovatus, however with out realizing extra about how Becklespinax regarded it’s onerous to say)
- Primarily based on Acrocanthosaurus and Concavenator, Becklespinax was a big predator with distinctive ridges and sails on its again. These ornaments could have been for show, an indication of dominance, or a method to know the dinosaur belonged to a species (although nobody is aware of for certain)
- In all probability ate small to medium sized sauropods (primarily based on the place and when it lived)
- Initially Olshevsky assigned Becklespinax to Eustrptospondylidae. However in 2003 Nash assigned it to Allosauroidea. Different researchers say its Tetanurae incertae sedis, which suggests it’s unclear the place it falls within the group
- Allosauroidea is a superfamily that accommodates 4 familes (Metriacanthosauridae, Allosauridae, Carcharondontosauridae, Neovenatoridae)
- The oldest Allosauroidea dinosaurs are from the early Center Jurassic, in what’s now China
- They lived by the late Cretaceous
- That they had lengthy, slim skulls, three-fingers on every hand, and “horns” or decorative crests on their heads (Allosaurus is the most effective recognized)
- Tetanurae is a clad whose title means “stiff tails”
- Jacques Gauthier named Tetanurae in 1986, and so they embrace theropods extra carefully associated to fashionable birds than to Ceratosaurus
- They embrace most theropods, in addition to birds
- They appeared within the early or center Jurassic
- Massive spinosaurids and allosaurids lived within the late Jurassic and early Cretaceous (significantly Gondwana), however died out earlier than the top of the Cretaceous (could also be due to competitors from abelisaurids and tyrannosaurids). Now fashionable birds are the one dwelling animals within the Tentanurae clade
- Carcharodontosaurids are a household named by Ernst Stromer in 1931 to incorporate new species of Carcharondontosaurus. In 1995,
- Giganotosaurus was added to the household, and a few paleontologists contemplate Acrocanthosaurus a part of the household
- The title means “shark toothed lizards”
- They had been carnivorous theropods
- The most important had been 46 ft (14 m) lengthy and the smallest had been 20 ft (6 m) lengthy
- Spinosaurids and carcharondontosaurids had been the biggest predators within the early and center Cretaceous in Gondwana
- Enjoyable reality: The formation of the Isthmus of Panama (between 2 and 15 million years in the past) might be an important geological occasion since dinosaurs went extinct. It:
- Separated the Caribbean sea from the Pacific, inflicting a rise in diversification in these areas whereas merging North and South america
- Pressured many South American animals to go extinct, as a consequence of North American animals, though some South American animals made it in North America as effectively
- Created The Gulf Stream
- Made Europe and Japanese North America hotter
- Made the Atlantic to change into extra salty then the Pacific ocean