Poposauroids: Theropods before Theropods

Poposauroids were a distinctive and long lived group of Triassic Pseudosuchians that are renowned for their very Theropod-like appearance. While early basal forms were quadrupeds, more derived genera developed bipedal postures and in some cases toothless beaks. Poposauroids were highly diverse in terms of lifestyle, including apex predators, small agile runners and heavy-set herbivores. Originating in the Early Triassic, the group became extinct at the end of the period.
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[@brandonshmandon1799]

Convergent Evolution really is a thing of wonders

[@dr.polaris6423]

It sure is!

[@sirmeowthelibrarycat]

@Ciaran Eldrett 😖 You appear to have been absent from punctuation classes! Your comment in its present form is almost unreadable.

[@miguellilly8859]

Indeed!

[@a.r.h9919]

@Ciaran Eldrett Does tuataras were introduced in let's say Australia and south america (one of it's former places) it's pretty likely they will radiate with the different conditions and niches available, they could evolve into big herbivores like iguanas, semi aquatic species, small lizard like generalists or even komodo dragon or monitor lizard forms, in pretty special case a limbless or gliding species maybe even turtle like convergence. It's more likely to be honest for monitor lizards to evolve into a dinosaur like forms

[@a.r.h9919]

@Ciaran Eldrett the modern tuatara isn't really well adapted for warmer climates but that was an adaptation to enduring the cold months in new zealand, besides that is the main engine for evolution and more for such a fast evolving creature as the tuatara: climate change, it's just giving them a little time and a niche to adapt, evolution can be quite fast and one of the best examples is in reptiles

[@matthiasfloren2610]

The Triassic just shows how prolific life is even after a great mass extinction

[@doc7000]

From other sources, predation limits the sizes of smaller animals since if they get any larger then suddenly become food for something bigger. This is why during the time of the dinosaurs mammals stayed so small and ended up living their lives mostly at night (resulting in the loss of color vision for most mammals). The larger sizes meant that when the food supply shrunk the larger animals die off first and once things recovered those mammals can suddenly grow in size getting super large with the largest one (and the largest known animal to ever exist) being the blue whale.

[@Squeam9750]

6:48 Ngl this creature looks like something out of fiction. Like a Frog and a Dinosaur had a mix up and made this creature.

[@dr.polaris6423]

Many Triassic animal look like weird hybrids of animals around today!

[@hoodedtroodon2901]

Nah, more like a chameleon had a child with a bird Edit: when i said bird, i was refering to the colors and the beak looking bit

[@Ratchetcomand]

Evolution is so strange. It's amazing how they look like Dimetrodon when they exist millions of years later.

[@dr.polaris6423]

I know that fascinates me as well. Dimetrodon the Proto-Mammal and Arizonasaurus the Pseudosuchian Archosaur looking so similar.

[@alexanderclass1244]

Dr. Polaris do you take requests if so at some point can you talk about the entelodonts ( they are my favorite cenozoic animals).

[@thedarkmasterthedarkmaster]

If it wasn't for the Triassic extinction these things would have dominated the Mesozoic

[@dr.polaris6423]

Absolutely!

[@thedarkmasterthedarkmaster]

@@dr.polaris6423 You know one must wonder what the world would be like if the Triassic extinction was different, It's not as popularly depicted as either the End cretaceous of the End Permian extinction

[@nathanisdank9208]

3:08 “the creatively named Arizonasaurus” 😂

[@alioramus1637]

Pseudosuchians like Poposauroids were very successful during the Mid-Late Triassic especially in the northern hemisphere. As usual outstanding content.

[@unclescar5616]

I used to think the triasic boring but I beginning to realise it was too weird to be so.

[@erikwolff2942]

Finally, my Favorite bear Doctor with my Favorite kind of content c:

[@dr.polaris6423]

Glad you like it!

[@caviramus0993]

Don't lie that they are your favourite archosaurs, we've been through the same text each time Triassic archosaurs are discussed, great vid ;)

[@TheScrootch]

The Triassic period is so fascinating!

[@theburgerking1236]

I’ve got so much more to learn about the Triassic period, geanosucus also makes me think of a prototype spinosaurus

[@fenrirgg]

I didn't know that evolution was trying the bipedal morph before the dinosaurs.

[@erichtomanek4739]

And so, inevitably, the end of the Triassic nears....... (cue the menacing soundtrack). POP goes the Sauroid! . Until today I had never heard of poposauroids. I am glad to have learnt about them.

[@thelaughinghyenas8465]

Very nice, very informative. I really love convergent evolution - "looks like but definitely isn't" species. Also, your production is getting more skilled, in particular your audio balance and your audio editing. Close your eyes and listen to this video and one of your early ones and you will very much hear the difference!

[@Minish4rk360]

Yeah same thing here I also love it when an animal looks like something but isn't really something It's just cool to me for some reason

[@kateaveryavery1342]

Theropods before theropods? Well that is interesting.

[@dynamosaurusimperious2718]

Basically from what I'm seeing from the thumbnail and reading from the title,is that the Poposauroids are just some weird bipedal omnivores,so that's quite interesting and very cool/sick. And cause it's Dr Polaris video,it's very AWESOME.( Also hope y'all have good day. )

[@dr.polaris6423]

Thank you so much!

[@dynamosaurusimperious2718]

Your welcome

[@mayday6916]

I didn't know there were so many dinosaur "look-alikes"! So many different varieties of animals and ecosystems from a distant time... It never ceases to fascinate me, these complete worlds developing again and again. Thanks for the video!

[@HoundofOdin]

"Hello everyone, Dr. Polaris here." I cannot describe just how much better hearing that phrase makes my day.

[@dr.polaris6423]

Thank you!

[@jonathan_narain1189]

Can you do a speculative evolution video on what if the pseudosuchian evolved flight? I think it’d be an interesting video considering the group has dominated every other niche.

[@The_SOB_II]

Pseudosuchian birds, what an interesting concept. I feel like you’d have to know a lot about the anatomy of various groups of animals, like Proto birds, theropods, and various groups of pseudosuchians In order to figure out what pre-adaptations would’ve had to occur

[@ANTSEMUT1]

🤔🤔🤔

[@ANTSEMUT1]

The Triassic period always reminds me how boring the animals look in our holocene period.

[@canis2020]

"Rawr!" (Good job) - Mr. Dino

[@dynamosaurusimperious6341]

Basically these pre-theropods,are quite weird,yet awesome. And the name: *Poposauroids* ( genius)( also this video was very nice,and hooe everyone the best sunday. )

[@surgeonsergio6839]

"Arizonasaurus" more like "Retrospinosaurus."

[@blainev1596]

Is that Zandalar music I hear in the background? Lol good choice. That music suits the prehistoric vibe perfectly. Great video! Can’t believe I had never heard of this group before. : )

[@dr.polaris6423]

Glad you picked up on the reference! I thought it fits the Triassic very well.

[@birdwatchingwithdrrajasaur4410]

It's interesting to see all the time the sail back evolved convergently

[@ShadySheev]

Almost seems like dinosaur-like creatures were unavoidable. If the archosaur branch of true dinosaurs had not evolved then members of the pseudosuchian branch would have almost certainly filled all those niches. Evolution is amazing.

[@sirmeowthelibrarycat]

🤔 Yes, indeed, it is! Kind regards from England 🏴󠁧󠁢󠁥󠁮󠁧󠁿.

[@thedoruk6324]

2:44 - That resembles Spinosaurids situation so much tho

[@Internet_Simian]

As a native spanish speaker, the name of this clade of reptiles is a mine of gold for mockery and meme stuff

[@furatceylan8]

love these videos of yours. 1A narration and always interesting!

[@dr.polaris6423]

Thank you!

[@_robustus_]

Bravo! I had no idea poposauroids were so diverse.

[@ericastier1646]

Some very talented hand drawers there. Really works of arts in these pictures.

[@raminagrobis6112]

Some bipedal poposauroids look a little like the old representations of large (true) theropods such as Allosaurus or Tyrannosaurus, whose tail laid on the ground - although I can't be sure the posture shown for them in this video is actually accurate.

[@derrickbonsell]

A lot of the genetics that were expressed in dinosaurs clearly existed in pre-dinosaur archosaurs.

[@impishinformation7237]

One of the illustrations in this video came from a book I had as a kid and I’ve always wanted to learn more about them but have never known what the larger group was called, just the one species. Thank you!

[@carmelosaurus7480]

When theropods are my favorite grouping of dinosaurs in combination of the name of your video. Along with fact I adore convergent evolution. Then you’ll almost immediately have, my attention my good sir.

[@The_SOB_II]

How punctual

[@carnotv6136]

Truly fascinating as is all of creation.

[@ProfezorSnayp]

Creation suggest a creator. Evolution does not require one.

[@fredhrodrigues9019]

I love your channel, it brings me great memories from Paleworld. Thanks for this!

[@sosa9754]

Just discovered your channel. This was an excellent video. Looking forward to bingewatching your channel and watching all your future videos. Keep up the great work!

[@Alberad08]

Fascinating video - thanks a lot for uploading here!

[@chancegivens9390]

Great video! You've managed to teach me more about prehistoric life then the vast majority any kind of website or place I've went to that I say thank you.

[@void9165]

Damn im so hungry for your content. Keep the good work

[@Kurotitan7125]

Recently the toy company Mattel made a toy of Poposaurus for their Jurassic World toyline, and the toy is very accurate to the depictions of Poposaurus, even down to the scales

[@hobart0011]

Very original topic. Thank you for this. I subscribed

[@user-ce6nz8ht3b]

The channel im looking for.. You got my subs buddy keep em coming!

[@scepticchristian]

Nice video. Looking forward to the Zenarthan video. Thanks.

[@barc0deblankblank]

Given that these were probably high-metabolism animals (meso/endothermic?), would you rule out the presence of filaments in the stead of scales? I know that both are encoded for in crocs and aviable by the same gene, yet my initial assumption would be that the sail-backed ones lacked any extensive covering and might have had a lower metabolism. To my understanding, filaments (hair, feathers, pycnofibers) are the keratinous byproduct/excretion of a high metabolism.

[@RancidGravy]

3:13 That back leg tho. XD Razzle Dazzle.

[@codja_]

Could you do one on the some of the animals that were around in the time where the first vertabrae walked on land. And the heiarki (dont rember the name of the correct word). But do what you wanna please dont feel like you have to do this because i asked.

[@dr.polaris6423]

That’s a great idea. I was always planning on eventually covering early Tetrapods.

[@codja_]

@@dr.polaris6423 very poggers

[@xuanluu4873]

So about your alter earth project, what mammals survived into the holocene? Do they fill any megafaunal niches?

[@LordLebu]

I remember the article that came out in Bengali regarding Shuvosaurus, he is from my city.

[@victorsztorc511]

When are you going to do the tyrannosaurs dr Polaris?

[@marshmallowmountains4636]

6:40 I like how this person drew it with a fatty fat belly and then the legs are emaciated, lmao. I can't imagine big bois having the bodies and legs of things like axolotls and geckos.

[@redgrain3914]

It's like the End Triassic Extinction nearly wiped everything out, but didn't, and a related branch of the then-dominant species just started over and ended up in a similar place. What are the chances of that happening?

[@TedShatner10]

The Triassic mass extinction didn't seem quite as cataclysmic as the Great Dying and KT impact, which was probably why distantly related cousin species rapidly filled the role of the extinct dominant creatures of the Triassic epoch.

[@viperaputakeyteaparyou8237]

That polar bear with a hat and monocle in the beginning's really sick, what period is he from?

[@vincentgirgenti6033]

Dr Polaris, it would be really cool if you did a video about monotreme evolution

[@petersmythe6462]

Mommy can we get a Spinosaur? We already have a spinosaur at home! The Spinosaur we have at home:

[@flightlesslord2688]

god these were cool. Theyre so... weirdly cool. Like they just look like extra dragony dinosaurs. Or like outdated depictions of dinosaurs, they look like dinosaurs from the 18th century to the 50s and thats really cool.

[@slimnnw]

Never been here this early

[@thevenbede767]

Were Shuvosaurids digitigrade? I've noticed many drawings of them as such.

[@seanledden4397]

The most basal poposauroid was semi-aquatic? I think there's an interesting story here. (And....I'm confused. Because later in the video you mention more derived forms, but they go back to the early Triassic, whereas the "most basal form" comes from the middle Triassic....?????)

[@cosmo6122]

I love this channel

[@christosvoskresye]

Lotosaurus looks suspiciously like a stegosaurus analog. I have to wonder if the plates and sail played similar roles.

[@The_SOB_II]

Hey good stuff. Just wondering, why do you pronounce genera “gen air a”? Is that a British thing?

[@dr.polaris6423]

I’m not sure, but you are probably right about it being my accent.

[@salazarbeedo1718]

I wish the walking with series would have done more with the Triassic.

[@entombedmachine1518]

It’s crazy to think that all of the diversity of today’s ecosystems are all related and interconnected. We have all the genes of extinct species within us.

[@Amc933]

Thanks!

[@miguellilly8859]

There my favorite as well!

[@itsjustalf7747]

Happy to be the 10th like

[@kyoatbites7865]

have any sail backed critters been found inhabiting colder regions ?

[@petersmythe6462]

Imagine if the dinosaur lineage had gone extinct but the pterosaurs and pseudosuchians survived? That would be an entirely different Jurassic and Cretacious, and with some random adjustments in climate caused by that change, quite possibly no K-Pg extinction.

[@othellotyrant3152]

Some of these creatures look very similar to crocodiles.

[@mcstabba]

Well they are pseudosuchians and the only remaining pseudosuchians are the crocodilians so not to unexpected I would guess.

[@othellotyrant3152]

@@mcstabba the African fossil of sarcosuchus and India having the only Ghariel today is another example of these amazing creatures.

[@Oszczywilski]

That they look similarly to early dinosaurs, nothing strange, just convergent evolution. But I also want to point at something. When they died out at the end of triassic, it was like 50M years, or less of since their last common ancestor with dinosaurs. A similar stuff to creodonts and true carnivorans in the cenozoic. When the last creodont died out 9M years ago, it was a similar period of time since his last common ancestors with the carnivorans. It is also somewhat a matter of mental image. We all have a nice shelf in our imagination labelled "dinosaurs", which we treat as related and belonging to one group/family (not a family in a systematic sense, but in a common meaning of the word). So even about the late createrous dinosaurs we think that they are closely related to each other, a bunch of similar stuff. When in reality, between a triceratops and T-Rex is far far more millions years of separated evolutionary paths since the last common ancestors, than between the late triasic dinosaurs and poposauroids.

[@captainstroon1555]

In today's episode of "dinosaur or not" we have bipedal crocodiles

[@jkb2016]

Missing important fun fact: in German, "Popo" means bum (butt)

[@davidls187]

In Spanish it means Poop, so...

[@leechild4655]

Extinction events always produce extraordinary new life forms. We see what was but, what would we see 120 million years from now. Some common-looking things sure but many highly sophisticated animals we might be spellbound by. Not unlike ones we have now that leave us spellbound, as it were,

[@maozilla9149]

good show

[@geoffzuo9831]

I've heard of a creature called carnufex and it looks a lot like poposaurus. They related?

[@SirEnd3r]

Why in the early days of life spins and sails were so common?

[@williamchamberlain2263]

Good question

[@swedreamhack5308]

Poopoosaurus in a fully pillar erected posture. Alright that sounds like something.

[@praetorianrex5571]

Do these creatures have plantigrade feet?

[@dantewhite9117]

The mystery of Godzilla has finally begun solved.

[@bamikroket]

Why did they name it after Mr. Popo? I don't see the resemblance.

[@petersmythe6462]

Poposaurus looks like the raptors from Jurassic park lol.

[@unlovednekochan94]

damn evolution is weird

[@antoniomv9444]

Ah yes, my favorite animals: the poop reptiles.

[@Huy-G-Le]

Imagine try to explain that they are not dinosaur, to a child.

[@daemonvelaryon5617]

Did any of the Poposauroids have feathers???

[@ruhalajn]

The skeksis of the triassic

[@samsalamander8147]

1:45 looked like a spinasaurus

[@ionidhunedoara1491]

I daresay those pop-a- steroids look like a rather pumped up lot. Well, bring them out and have a go..

[@altithoraxperotorum5133]

Cover the homalodotheres in a video

[@jamesadam4415]

YEE

[@nickkorkodylas5005]

Popos is an infantile term of saying "butt" in greek.

[@parmaxolotl]

8:30 lmao I highly doubt these creatures were feathered

[@ammagnolia]

Are you really a doctor??

[@altithoraxperotorum5133]

What cryptid theory does make the least sense to you. To me it's the Bigfoot is gigantophitecus theory. First of all the estimated size of three meters would make gigantophitecus way too big for most big foot species. The only one coming close to this size is the hairy man. 2. Gigantophitecus is only known from south east asia. There is no evidence of him being ever presented on the asian continent itself so if he even wasn't in asia than it's extremely unlikely that he ever made it into north America 3. Gigantophitecus was like orang utangs a jungle living creature so he probably wouldn't be able to survive cold winters. 4. Gigantophitecus was strictly herbivoreus with it's main food been bamboo and as what is said from many sightings Bigfoot and all the other man ape monsters are carnivores

[@esbendit]

Plesiosaur loch ness monster is also pretty bad. 1. It is a late surviving plesior 2. the lake cannot support a healthy population of animals that size. 3. the lake was carved by glaciers during the ice ages, making it unsuited as a refugium. 4. No known plesiosaur had a swan neck posture, and such a posture would only make sense for a surface based lifestyle, making sightings likely.

[@altithoraxperotorum5133]

@@esbendit 5. Plesiosaurs are air breathing animals so they would have to go on the surface many times wich them more people would see them

[@b52incoming.48]

You should do a battle between allosaurus vs majungasaurus.

[@Arialovessyou]

Hehe popo

[@Spudmay]

Algorithm