Evolution of the Dinosaurs YouTube video by Manabu Sakamoto PhD

One of Dr. Sakamoto’s major interests is
“How did major groups of animals radiate?” So we have similar interests. This slide show lecture apparently on ZOOM (or a similar format) is 56 minutes in duration and was streamed live March 12, 2021.

Sakamoto received his PhD from the U of Bristol in England,
which does not bode well. That’s where too many recent myths about pterosaurs and dinosaurs had their genesis.

In his slide labeled ‘Birds are dinosaurs’
Sakamoto includes an illustration of Microraptor (Fig. 1), which has wings and feathers, but is not a bird in the large reptile tree (LRT, 1817+ taxa), but a bird mimic arising from Ornitholestes  (Fig. 1). Sakamoto had so many birds to choose from, but chose a non-bird.

Figure 1. Changyuraptor to scale with Ornitholestes, Scriurumimus and Microraptor.

Figure 1. Changyuraptor to scale with Ornitholestes, Scriurumimus and Microraptor.

In his slide labeled ‘What makes a dinosaur?’
Sakamoto includes four illustrations and photos of four traits he reports are common to dinosaurs. That’s called a “Pulling a Larry Martin” because it is fraught with convergence in various non-dinosaurs. He should have used the “Last Common Ancestor (LCA) hypothesis.

In his slide labeled ‘Dinosauromorphs’
Sakamoto includes lagerpetids and notes reduced toes 1 and 5. That’s not true of sauropods, which have a huge toe 1. Lagerpetids are not related to dinosaurs when more taxa are added. Lagerpetids are proterochampsids convergent with dinosaurs. He lists Marasuchus among the dinosauromorphs. In the LRT it nests as a basal theropod even though the acetabulum is 90% not-perforated, as in ankylosaurs (see “Pulling a Larry Martin” above).

So far, not so good,
and we’re only 16 minutes into the video. So glad I did not waste time and money getting an education at the University of Bristol, like Dr. Sakamoto did. The professional academic Bristol program in dinosaurs is evidently behind the times.

In his slide labeled ‘A modern definition of Dinosauria’
Sakamoto correctly reports, dinosaurs are “members of the least inclusive clade containing Triceratops horridus and Passer domesticus (house sparrow),” but incorrectly includes ‘Dinosauromorphs’ as outgroup taxa between Crocodylomorpha and Dinosauria. In the LRT there are no taxa between Crocodylomorpha and Dinosauria.

In his slide labeled ‘major dinosaur groups’
Sakamoto reaches into the past to divide dinosaurs into Saurischia and Ornithischia. By contrast the LRT, with more taxa, divides dinosaurs into Theropoda and Phytodinosauria (Fig. 2) with a set of herrerasaurids preceding this split. So far Sakamoto is extending the reputation of U of Bristol for perpetuating myths.

Figure 2. Subset of the LRT focusing on the Phytodinosauria with Buriolestes at its base.

Figure 2. Subset of the LRT focusing on the Phytodinosauria with Buriolestes at its base.

In his slide labeled ‘…but there is only one true tree!’
Sakamoto presents his best estimate from data: an unresolved branching of Sauropodomorpha, Theropoda and Ornithischia. Based on what Sakamoto has presented thus far, the problem in Sakamoto’s presentation appears to be due to taxon exclusion. The LRT fully resolves the origin of dinosaurs by including more taxa. So why go to Bristol when you can learn with complete resolution online here?

In his slide ‘Dating dinosaur origins’
Sakamoto attempts to time the origin of dinosaurs, but without resolution or precise timing. In the LRT the dino-croc split occurred prior to the Ladinian (Late Middle Triassic) when the most primitive LCA of Dinosauria, PVL 4597 roamed South America.

 

Figure 4. The PVL 4597 specimen nests at the base of the Archosauria, not with Gracilisuchus.

Figure 3. The PVL 4597 specimen nests at the base of the Archosauria, not with Gracilisuchus.

In his slide ‘Early dinosaurs spread across the globe,
but started out just in the Southern hemisphere’ Sakamoto graphically considers Ladinian Lagerpeton and Asilisaurus ‘Basal Dinosauromorpha’, but verbally calls them early dinosaurs. Neither are dinosaurs in the LRT. Asilisaurus is a poposaur, the proximal outgroup for the Archosauria. Like many of his contermporaries, Sakamoto completely ignores the basal bipedal crocodylomorphs that the LRT nests as the proximal outgroup to the Dinosauria.

At this point we’re 30 minutes in
and very little Sakamoto has reported so far is verified by the LRT.

So we’re going to stop here.
The ratio of myth to fact is way too high. The ratio of missing taxa to included taxa is also way to high. Sakamoto now teaches at the U of Lincoln. If you are thinking of spending tuition money there, you have this preview to help you in your decision.

 

 

 

 

 

 

 

 

 

 

4 natural history museum tours on YouTube + 2 bonus videos

Today: Some short YouTube museum tour videos without narration
and two bonus videos on continental drift and on becoming a PhD.

1 Wyoming Dinosaur Center at Thermoplis:

2 San Antonio Museum in Texas:

3 American Museum of Natural History in New York:

Field Museum in Chicago:

Bonus video #1
the best I’ve seen on the history of continental drift:

Bonus video #2
A young man on TEDx discusses the ups and downs of PhD students.

Given these strict parameters, high expenses and meager, postponed rewards,
it’s no wonder why so many PhDs and PhD candidates dismiss and attempt to suppress published and unpublished work by enthusiastic outsiders without a science degree. They must see ReptileEvolution.com as taking an academic short-cut. Not paying the price. Not doing it the ‘right’ (= traditional) way.

By contrast I see ReptileEvolution.com as a retirement project. Every day I simply add taxa to a growing phylogenetic analysis. Sadly, no one with a PhD, worse yet: no one else on the planet, has wanted to do this for the last nine years. So, at present, there is no competing analysis with a similar taxon list. Given that the typical PhD project can last for two to eight years, a competing cladogram would make a great PhD project!

Dinosaurs in the Wild video, plus a backstory video

There’s a new(?) dinosaur exhibit
in England and several visitors have uploaded YouTube videos of it. Most of these are at least one year old, so I may be the last one to learn about this.

Visitors go back in time
and every so often put on 3D glasses to see dinosaurs outside the ‘windows’ of the exhibit. Looks like a thrill a minute with up-to-date dinos.

Plus
Dr. Darren Naish provides a behind-the-scenes YouTube video.

Figure 1. When they had to animate Quetzalcoatlus, they got rid of that membrane down to the ankles.

Figure 1. Evidently, when they had to animate Quetzalcoatlus, they got rid of that membrane down to the ankles, distinct from all previous illustrations of Quetzalcoatlus, but only when standing. Baby steps…

References

For more YouTube listings click here.

 

On a lighter note… Zeppelin vs. Pterodactyls (1936)

Click to play this YouTube video link.

It’s an old Republic Studio serial.
I think you’ll recognize certain precursors to Indiana Jones here (openly acknowledged by Spielberg and Lucas). The ‘pterodactyls’ don’t show up until about 3:45 and they are hand/string puppets.

Back to more serious matters tomorrow.

The YouTube videos of Ben G Thomas

Just wanted to alert readers
to a series of paleontological YouTube videos by Ben G Thomas. All are well done.

Of course,
several of the videos are sprinkled with outdated traditional thinking and need a bit of updating based on results from the large reptile tree. But overall most are so well presented that their benefit outweighs any objection.

There must be over a dozen paleo videos
in the Ben G Thomas channel. These represent just a few samples.

References
https://www.facebook.com/bengthomas42/
https://www.youtube.com/channel/UCDSzwZqgtJEnUzacq3ddoOQ

New online course on birds and pteros from Dr. Phil Currie

This is part of a new video series on theropods and birds
Click to view. YouTube video on birds and pterosaurs from Dr. Phil Currie

Click to view. YouTube video on birds and pterosaurs from Dr. Phil Currie

YouTube caption:
Week 4, Lecture 3 for the online course “Paleontology: Theropod Dinosaurs and the Origin of Birds”, taught by Philip John Currie, Ph.D. All rights belong to Coursera and University of Alberta. For educational purposes only. Happy learning!
The new video
features all your favorites: Microraptor, Archaeopteryx, Deinonychus and some old John Ostrom hypotheses.
I added this comment:
The use of cartoons without skeletons undermines the scientific value of this project.
Microraptor does not nest with dromaeosaurids in the large reptile tree, but with Ornitholestes and tyrannosaurs.
That cladogram does not document a secondary flightless condition in dromaeosaurids.
Pterosaurs are not related to dinosaurs, but are tritosaur lepidosaurs derived from taxa like Huehuecuetzpalli, Macrocnemus and Cosesaurus.
Pterosaur flight membrane does not attach to the lower leg. See

Feathered T-rex video: Excellent!*

The best video* I’ve seen on feathered dinosaurs.
*But note: their gliding Anchiornis forgot how to flap. Flapping came first. Then flapping with bipedal climbing. Then flapping with flying. Birds don’t come by gliding except to rest while airborne. Same with bats (if any glide ever). Same with pterosaurs. Let’s take gliding out of the equation for the origin of flight. That’s widespread antiquated thinking not supported by evidence. If you glide you do not flap. If you flap, some of your ancestors may learn to glide.

Click here or on the image to play.

Marching Dinosaurs Video

Figure 1. Marching dinosaurs video. Click to view.

Figure 1. Marching dinosaurs video. Click to view.

Make sure you see this one.
Click on the pic or here to view. I am very impressed by the accuracy and quantity shown in this video.

And, of course,
I’m a big fan of humans and dinosaurs to scale AND walking videos!

A few days ago
I showed an early term pregnant pterosaur. Just a reminder (because I forgot, too!), that was not the first pterosaur with extra bones inside. Here’s the other one.

New Origin of Birds YouTube Video

Just in time for Turkey Day!
We’ve seen a lot of data coming in recently with news on Archaeopteryx and reconstructions of basal birds together with their addition to the large reptile tree. In an attempt at simplifying the evolutionary process, here is a YouTube video of < 6 minutes that pulls the origin and evolution of basal birds together based on the cladogram recovered at ReptleEvolution.com.

origin_of_birds_588.jpg

Click to view YouTube video.

Happy Thanksgiving
to my USA readers.