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How to pronounce sauropodomorpha in English?

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Welcome, my name is Benjamin Burger, for some time, I wanted to do a video on a new radical
idea that was put forth on dinosaur relationships and classification that was published last
year in 2017 in Nature, which has either really radical implications for dinosaur classification,
or is just a bunch of handwaving and will fade slowly from history.
I wanted to talk about it, because to tell you the truth, I’ve kind of ignore this
new idea, but enough people have mentioned it to me, that I thought I would do an unbiased
video on this rearrangement of the dinosaur tree.
So a quick backstory.
In 1887, there was a British paleontologist named Harry Seely, who took an interest in
dinosaurs and other extinct animals.
Dinosaurs, which had first been described from fossils in Britain, but by the 1880s
were now known from many other parts of the world, and enough skeletons had been found
from the American West.
He noticed with these dinosaurs, they could be divided into two major groups.
He documented a unique defining feature in the arrangement of the pelvis.
Some dinosaurs had a forward projecting pubis bone, while others had a backward projecting
pubis bone.
In a lecture, and follow up paper in 1888, he defined two new suborders of Dinosauria.
The Saurischia (the lizard-hipped dinosaurs) and the Ornithischia (the bird-hipped dinosaurs).
Since 1887, all paleontologists have supported this bifurcation of the order Dinosauria into
these two groups.
In 2017, a graduate student named Matthew Baron at Cambridge published an article with
two well-known British paleontologists offering a different classification.
Now, it is not unheard of a graduate student with an inordinate fondness of dinosaurs to
take on a massive study of dinosaur relationships.
These modern studies involve examining each fossil and characterizing every bump, groove
and protuberance on fossilized bones into a binary code of states, which are then feed
into a computer to analysis relationships between different species.
Unlike, what Harry Seely did, which was to find a single large unique character that
defined each group, these modern studies look for the minutiae of features that culminate
in enough statistical support to recognize new groupings of animals.
Previous studies using this technique have supported the idea of Saurischia and Ornithischia,
as the two unique groups of dinosaurs, and no one had questioned this arrangement before.
But Matthew Baron’s results were slightly different.
He found that Ornithischia was paired to some by not all Saurischian dinosaurs.
His paper defined a new grouping of dinosaurs that included all of the previous Ornithischian
dinosaurs, plus some previous members of the Saurischian dinosaurs, including Coelophysis,
Eoraptor, and Eodromaeus.
This new group they named: Ornithoscelida.
They also found the traditional therapods Herrerasaurus and Staurikosaurus as ancestral
to Sauropods, which had never been proposed either.
The study was replicated by other researchers, who did not find the same results.
In fact, in a reply to the original article, a replicate study found the traditional grouping
of dinosaurs into Ornithischia and Saurischia noting some mistakes in some of the characters
and how they were scored, particularly for the very fragmentary fossil of Pisanosaurus,
recently proposed to be the oldest Ornithischian dinosaur, although this assignment is highly
debated.
Personally, I found that this replicated tree a much better fit in terms of the placement
of Eoraptor within Sauropodomorpha, which in Baron’s tree was positioned within “Theropods.”
There are some obvious characters in the hand of Eoraptor (such as the twisted shaft of
the thumb) indicating that it belongs within the Sauropodomorpha a feature highlighted
in the paper by Paul Sereno and others published in 2012.
The fact that Matthew Baron’s tree did not resolve this relationship made me a little
critical of this new rearrangement of dinosaurs…
Now I’m not saying that this study is without merit, and that we should ignore it, but a
healthy bit of skepticism might be warranted.
So let us look at what characters support a relationship of Ornithischia, with some
members of the Saurischia, that define this new grouping, called Ornithoscelida.
The supplementary files list 21-character changes that support this new arrange, 10
of these are proportional or slight shape differences in bones, that likely had little
in the way of an adaptive difference in functional aspects of the how the animal lived.
The remaining eleven characters are a mix, including the presence or absence of a hole
near the nose in the skull, to the shape of the cheek bone, to the position of a small
hole in the back of the skull, the extent that the fibula articulates with the ankle,
which may-be related to a larger body size, and also the fusion of the toe bones.
These characters may reflect morphological differences related to larger body sizes,
grouping larger Triassic dinosaurs, like Herrerasaurus and Plateosaurus together, and smaller Triassic
dinosaurs like Eoraptor and Lesothosaurus together.
There is one really odd character state difference
listed, Medioventral acetabular flange of ilium, closes the acetabulum: 0, present,
partially or fully closes the acetabulum; 1, absent.
Now this character should be absent in all dinosaurs, since the defining character of
the clade Dinosauria--- an open acetabulum, but the wording partially or fully closes
the acetabulum, shifted the origin of the open acetabulum later within some dinosaurs
with “partially closed” scored the same as fully closed, a subtle difference, but
an important one.
The last character, and maybe the one that comes to define the group is the presence
of dorsosacral vertebrae.
A dorsosacral vertebrae is defined simplistically as a vertebra that is connected to the hip
bone.
This would be help stabilize the hip and spinal bones.
However, later saurischians also have this trait, particularly the Sauropodomorpha which
have upwards of 3, the fact that Eoraptor is recognized as a basal member of this group,
while others suggest that it is a basal Sauropodomorpha has me suspect that the development of dorsosacral
vertebrae may have proceeded this early split between Theropoda and Sauropodomorpha.
And this trait is difficult to see in very fragmentary Triassic dinosaur fossils.
As you can tell, I’m still highly skeptical of this new arrangement of dinosaurs.
I think it is safe to say that the idea of Ornithischia and Saurischia is going to remain
in the textbooks.
However, I think this study brings up an important point, that it is very likely that Ornithischia
evolved from a Saurischian ancestor, and that that ancestor may have been very similar to
early Theropods like Eodromaeus and Coelophysis.
It would not surprise me that with additional fossil discoveries that Ornithischian dinosaurs
will be paired with various early Saurischian dinosaurs.
Some-time in the Triassic a geographical widespread, small agile bipedal dinosaur, developed a
new and adaptively important Ornithischian hip, which led to a successful new group of
dinosaurs.
It is interesting to note that Harry Seely viewed these two groups having separately
evolved from a non-dinosaur ancestor, and that might be the case too.
In fact, if we could find a non-dinosaurian Silesaurid fossil, with both a closed acetabulum
and an Ornithischian hip, which could prove Seely’s original notion right, and blow
the minds of dinosaur experts around the world!
If that were to happen, the term Dinosauria would become obsolete.
In conclusion, I think Ornithischia and Saurischia are going to be around for a while, so don’t
worry about having to memorize a new classification of dinosaurs, at least not yet.
Check out the links below if you want to read more about this radical new idea of dinosaurs,
as well as other YouTubers who have taken on this topic.
Thanks for watching!
I want to thank my Patreon supporters….
Arctodus18.11, Dan Capshaw, Justin Bovee, Paolo Luzzatto-Fegiz, and all my trilobite
supports.
Without your support this channel would not be as active... and these videos would exist
only in my mind, or in lectures to my classrooms.
So thank you, it keeps me going knowing there are folks out there who are interested in
these videos.

Welcome, my name is Benjamin Burger, for some time, I wanted to do a video on a new radical

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sauropodomorpha::noun | Spocien Dictionary

sauropodomorpha

noun

gigantic herbivorous dinosaurs having huge bodies with long necks and small heads: Prosauropoda and Sauropoda (apatosaurus, diplodocus and titanosaurs)

Type	Words
Synonyms	suborder sauropodomorpha
Type of	animal order

How to pronounce sauropodomorpha in English?

sauropodomorpha::noun | Spocien Dictionary

abandonment

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