Episode 434: Therizinosaurus had weak claws

Episode 434: Therizinosaurus had weak claws. Did Therizinosaurus have claws that had been too massive to be helpful? Did Alvarezsaurus have claws that had been too small? How dinosaurs performed, how raptors used their claws, and dinosaurs in area.

Information:

Alvarezsaurs and therizinosaurs had been bizarre, and the large claws of Therizinosaurus had been surprisingly weak supply

Scientists studied birds to determine how dinosaurs could have performed supply
Raptors most likely used their “killing claws” to pin their prey, fairly than slash at prey. supply

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The dinosaur of the day: Struthiosaurus

Nodosaurid dinosaur that lived within the Late Cretaceous in what’s now Austria, Romania, France, Spain, and Hungary

To not be confused with the ornithomimid Struthiomimus (which was extra bird-like)
Could also be some of the basal ankylosaurs
Regarded considerably like different nodosaurids, like Borealopelta

Walked on 4 legs, had massive shoulder spikes, had an elongate head, physique coated in armor, however no tail membership
As Garret put it after we talked about Struthiosaurus’ listening to in episode 274, it was “like an enormous tanky canine coated in armor and spikes”
Could have been a dwarf dinosaur

Estimated to be about 6.6 to 9.8 ft (2 to three m) lengthy and weighed about 660 lb (330 kg)
On the time Struthiosaurus lived, what’s now Europe was largely islands
In 2017 Norbert Frotzler, in a pre-print paper, reconstructed Struthiosaurus austriacus

A part of the 650th anniversary celebrations of the College of Vienna (in 2015)
Frotzler was requested to arrange a diagram of Struthiosaurus and introduced the reconstruction on the anniversary celebration
Paper was a proof of that reconstruction

Described Struthiosaurus as “conspicuously small” with an extended neck, and “most likely, it was feeding primarily on ants and termites, at the very least when a juvenile animal”
Kind species is Struthiosaurus austriacus
Eduard Suess, a geologist, discovered a dinosaur tooth in 1859 at a coal mine in Austria (on high of a stone pile)

Tried to seek out extra fossils, and ultimately they discovered a skinny marl layer with a number of bones (recent water deposit, a part of the Grünbach Formation)
Fossils saved on the museum of the College of Vienna, and never studied till 1870
Emanuel Bunzel studied the fossils and named just a few new dinosaurs, together with Struthiosaurus, based mostly on a part of the cranium and braincase

Named in 1871
Genus identify means “ostrich lizard”
Genus identify refers back to the birdlike-ness of the braincase

Species identify refers back to the provenance from Austria the place the fossils had been discovered
Bunzel additionally described different Struthiosaurus fossils and osteoderms, however he referred them to Scelidosaurus and Hylaeosaurus
He additionally described rib fragments that he thought had been from a large lizard, as a result of that they had double-headed ribs (which suggests extra joints between the ribs and vertebrae and subsequently the rib cage could possibly be extra cell), which he named Danubiosaurus anceps (after the Danube River—the identify is a nod to Mosasaurus which was named after the River Maas)

All these bones turned out to be from Struthiosaurus
Bunzel knew the braincase was from a reptile however the braincase was completely different from lizards and crocodiles (was low, compact, and had a gradual curve to the cranium roof)
Thought the braincase could possibly be from a dinosaur, however wasn’t positive, and thought it is likely to be a fowl based mostly on how the bones rounded and fused

Despatched a drawing and outline to Thomas Huxley, who agreed it was like a fowl
Bunzel wrote in his description of the fossils “with time, it may also be attainable to create an order Ornithocephala (“fowl heads”)”
Laborious to understand it was an ankylosaur braincase on the time as a result of it was the primary one described, and there have been solely fragments so the cranium appeared to be calmly constructed

Bunzel didn’t actually have osteoderms when he described the fossils
Nopcsa in 1902 discovered it was an ankylosaur, and in 1978 Walter Coombs mentioned it was a nodosaurid
At the very least three people of various ages of Struthiosaurus austriacus had been present in Austria, in response to Suberbiola and Galton in 2001

Was once many species of Struthiosaurus, based mostly on fragmentary fossils and materials that didn’t have distinctive options (nondiagnostic)
Animals which were discovered to truly be Struthiosaurus embody rataeomus,? ?Danubiosaurus,? ?Leipsanosaurus,? ?Pleuropeltus,? ?Rhodanosaurus,? ?Hoplosaurus
In 1881, Seeley examined Bunzel’s fossils and located lots of the bones, plates, and tooth had been a part of one dinosaur, which he named Crataeomus (which suggests “mighty shoulder”). Nopcsa later synonymized Crataeomus with Struthiosaurus

Turned out to be a part of Struthiosaurus
Three legitimate species at the moment: Struthiosaurus austriacus, Struthiosaurus transylvanicus (named by Nopcsa in 1915), and Struthiosaurus languedocensis (named by Garcia and Pereda-Suberbiola in 2003)
In 2003 Géraldine Garcia and Xabier Pereda Suberbiola described Struthiosaurus languedocensis, based mostly on a partial skeleton of an grownup present in southern France in 1998

Species identify refers to Languedoc, the area the place the fossils had been discovered
Struthiosaurus austriacus was smaller than Struthiosaurus transylvanicus and had shorter neck vertebrae
Struthiosaurus languedocensis had flatter dorsal vertebrae and a distinct formed ischium (pelvis)

Briefly talked about in episode 400, with the opposite Hateg dinosaurs
Nonetheless, “‘Struthiosaurus” transylvanicus is usually referred to in quotes
Fossils Nopcsa described embody elements of the cranium, vertebrae, a part of the shoulder, and armor

Coombs and Maryanska thought-about Struthiosaurus austriacus to be a nomen dubium
In 1997, Suberbiola and Galton mentioned the “Struthiosaurus” transylvanicus could also be legitimate however the fossils are most likely insufficient to point out its completely different from Struthiosaurus austriacus
In 2013, Attila Osi and Edina Prondvai tentatively assigned a humerus (arm bone), of an grownup dinosaur (based mostly on histology), present in Hungary to Struthiosaurus

Helps present that two nodosaurids lived alongside one another within the space, which suggests there was extra range in European ankylosaurs than beforehand thought
The opposite nodosaurid, Hungarosaurus, was nearly twice the dimensions of Struthiosaurus
Talked about Struthiosaurus in episode 374

Paper revealed in 2022 by Marco Schade and others
Re-examined the holotype braincase utilizing micro-CT scanning
Had comparatively brief semicircular canals (inside ear)

Massive semicircular canals make animals higher at balancing and extra delicate to go actions
Struthiosaurus additionally didn’t have a floccular recess, which helps stabilize imaginative and prescient when shifting your head and is linked to motor management
And had the shortest cochlear duct of any identified dinosaur, which most likely means it couldn’t hear very properly (perhaps somewhat higher than a turtle)

Authors additionally discovered a number of blood vessels across the mind which helps present it might have used additional blood vessels to chill down their brains
Taken altogether, means it most likely spent a number of its time alone, consuming, and wasn’t very energetic
Additionally talked about Struthiosaurus in episode 377 when Garret contemplated if it might depend on infrasound to listen to

Struthiosaurus might hear all the way down to about 300Hz (round Center C on a piano)
Beneath 20Hz is taken into account infrasound, so Struthiosaurus couldn’t use it (elephants and blue whales can although)

Enjoyable Truth:

Dinosaurs by no means noticed Halley’s comet.

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