The Life and Times of Tyrannosaurus rex, with Dr. Thomas Holtz

[@tonybusch8771]

Dr. Thomas Holtz Jr. is one of my paleontologist heroes.

[@Firealone9]

I love how he is easy to understand, and converts complex science jargon into language we can actually understand and keep up with.

[@Chewbaccafruit]

The shade he's throwing at Horner is just amazing.

[@DeepPastry]

Horner staked his rep on bad science from the Victorian Era. Worse, he fausted off his idiotic ideas during a vast sea-change in animal behavior thanks to little things like cameras and film and video tape and night vision capable cameras/lenses. Excluding vultures and hagfish, almost all the "scavengers" of old were proven beyond argument to be hunting predators. Horner chose to ignore that all these scavengers he was comparing T-Rex too would bring down their own prey most of the time; see hyenas.

[@SawdEndymon]

@@DeepPastry vultures *CAN KILL* They’ve raided chicken pens, wild guinea fowl, hell a swarm of them can kill a gazelle

[@DeepPastry]

@@SawdEndymon ... Never said they couldn't, just that isn't their main strategy for getting food. Unlike all the other "scavengers" who do hunt most of what they consume.

[@SawdEndymon]

@@DeepPastry I understand. Just a little interesting fact: The only true vertebrate scavenger (or at least, a good majority of its diet) are hagfish.

[@BHOLT08]

@Chewbaccafruit Hilarious.

[@laurachapple6795]

"Some of my colleagues... well, *one* of my colleagues..."

[@petfauna1445]

Probably the great 'Jack Horner'.

[@Indy44636]

​@petfauna1445 sure Mr chickenasaurus , t rex was a scavenger . Made two failed movies . Valley of the t rex , jurrasic park 3 .

[@EschenbachClock]

This is an excellent lecture. I can appreciate that he answers so many of the questions with "I don't know" rather than B.S. something on the spot. It encourages exploration for others!

[@jeffreygao3956]

He could give more definite proof if he were 66 million years old.

[@EAGLEVISION666]

@@jeffreygao3956 t rex never existed hes a liar. No fossils were ever discovered by native Americans or anyone in previous times

[@boyerbottomtext7235]

@@EAGLEVISION666 mhm yea sure

[@bigroncoleman11]

Chris Roberts Haha you don’t believe in lizards? Go home you’re drunk 🤣🤣

[@blackcosmos]

"Science isn't about learning things. Science is about learning how to learn about things. Its how we answer questions about the natural world." 👏👍👌

[@miscellaneousetc.4280]

He is a very likable person and so good at presenting this information. Love these lectures. Thank you Dr. Holtz.

[@StormsandSaugeye]

He was my professor back when I was pursuing my undergraduate degree in Geology. I still talk to him regularly.

[@tanehickey9887]

Storms and Saugeye go watch anime your off your head bruv

[@bran154]

Fuckin lying bastard

[@StormsandSaugeye]

@@bran154 And what makes you think I'm lying?

[@thomasmorgan9341]

I can binge watch these lectures for days. I still want to be a Paleontologist when I grow up.

[@boreopithecus]

It's a shame there aren't more lectures by Holtz online.

[@StormsandSaugeye]

Well you could always follow his facebook and twitter. He does the occasional write up and on occasion will post a study or another. Plus he is usually a speaker at balticon in Baltimore, held every memorial day. He was my old teacher. Great guy. I consider him a friend.

[@JoaoSantos-lv4rc]

check the NCAS channel he's got 4 there that i've found:) Still not enough though he's awesome.

[@eliburry-schnepp6012]

Seriously, he's such an amazing speaker

[@2005wsoxfan]

You only say that because he's another Fucking White Male.

[@pharmagator]

Well, David Home has plagiarized a significant portion of this lecture... So watch it again (with a British accent!)

[@marcospinheiro2518]

Great paleo-show indeed! That's why he's my favorite paleontologist! He's book (the one with Rey's illustrations) is also great and well written. He's one of dino fans who inspire me to write some books of certain dinosaurs as accurate as possible. Keep digging dinos hard Dr. Holtz!

[@jeffreygao3956]

That's one good book he's got!

[@calibersoul2012]

*For anyone wondering just who is this **_colleague_** Dr. Thomas Holtzis keeps referring to who believes t.rex was a scavenger*, it's obvious... Well, obvious if you have been keeping up on paleontology studies in regards to how t.rex really lived. Thomas Holtzis is *referring to the famous paleontologist, John R. Horner or as more popularity known as "Jack" Horner*. Horner is well renowned as a radical amongst head paleontologists and tend to have overly bizarre views in regards to the fields of dinosauria. Jack(as he's most known as) proposed that t.rex must have been a pure scavenger and held this belief for decades. However, it has largely been debunked; though t.rex likely did scavenged when given the opportunity, rather than relied solely on carcasses.

[@wratched]

You kinda gotta hand it to a guy so bullheadedly obsessed with his own ideas that he refuses to acknowledge basic reality. That's hard to do, particularly for a scientist.

[@Albukhshi]

Oh, trust me, he's not even the worst. That (dubious) honor goes to some dude named John Ruben. scienceblogs.com/tetrapodzoology/2009/07/17/birds-cannot-be-dinosaurs/

[@SamuelJamesNary]

wratched - Well... the hard thing is that since dinosaurs (outside of birds) have been extinct for so long, we really don't have much that we can be sure on with regard to their behavior. At best we can speculate based on what evidence we have and in comparison with modern animals... And while we have found bones of animals bitten by a T-Rex that survived the bite... all that concretely proves is that a T-Rex bit the animal while it was alive. It doesn't even necessarily prove that the T-Rex actually attacked the animal. Perhaps the Triceratops attacked the T-Rex or attacked the nest where the hatchlings were... After all, Cape Buffalo in Africa have been observed actually going into all out attacks to try and kill Lion cubs. The series "Big Cat Diary" in Kenya had two episodes in which a herd of buffalo stumbled on to an area where the "Marsh Pride of Lions" had their cubs hidden. The buffalo went all out to try and kill the cubs... In the first episode, they backed off when the Pride Males challenged the buffalo and in the second episode, they only left because the cubs had gotten into areas the buffalo couldn't and they lost interest... and that was after killing three of the lion cubs. So it is not outside the realm of possibility that some herbivorous dinosaurs would have an aggressive temperament and would go all out to remove real or imagined threats... Especially when one considers that a Triceratops has the weapons to confront an adult T-Rex directly... The more telling one was with the Hadrosaur that survived a T-Rex bite. Now, it MAY have an aggressive temperament... but they also lack the weapons a Triceratops has, which would make the idea of it attacking a T-Rex to destroy its eggs or hatchlings unlikely. But again... until we get a time machine, at best we can only speculate. I personally would tend to agree that it's more likely that T-Rex WAS an active hunter, as it wouldn't need to be as big as it was to be a pure scavenger. After all, while many Vultures and Condors are large birds, they aren't the largest birds in the world and there are a fair number of large Eagles that are larger than many Vultures and Condors, so they aren't even necessarily the largest "birds of prey." And in many cases today, you DON'T see scavenging birds driving wolves, tigers, lions, and bears off of carcasses. More often they wait until the predators have had their fill and leave before coming in... and with good reason, as lions and tigers have been observed swatting at vultures in the wild. And while bears and hyenas have been seen to drive lions or wolves off of their kills, they've also been observed to hunt on their own, so we know that bears and hyenas are not 100% scavengers.

[@kyle857]

Sam Nary Your scenario seems highly unlikely. Zebras and horses man.

[@WaterShowsProd]

I actually laughed out loud when he said, "Some of my colleagues, well, one of my colleagues..."

[@williamarthurfenton1496]

Jack Horner is annoying about his obvious bias against T-Rex. He openly admits he doesn't like them - though I would go one further and say he dislikes them. Seems pretty damn obvious that like most predatory animals, they will scavenge whenever possible, because it's less energy spent. But they will hunt when needed.

[@the888erkan888]

+William Fenton Its mind boggling how someone can "dislike" an extinct animal... is it the popularity he gets annoyed about? I think T rex fame mustve brought alot of money and opportunitys to the science of dinosaurs.

[@ProjectLDV]

+ErikM He's a paleontology hipster or at least a counter culture kinda guy. The mainstream and global hype of T.Rex irritates him so he tries to downplay it.

[@jeffreygao3956]

Last time I checked, dead stuff doesn't heal. An Edmontosaurus at the Denver Museum shows broken tail vertebra that HEALED. So it was attacked and beat the tyrannosaur. With a cripple no less.

[@Tenereus]

Jeffrey Gao There have been healed marks on triceratops and even ankylosaurus too. Basically aside from perhaps adult alamosaurus, nothing in its environment was safe from predation. Plus there's the binocular vision. No idea why any scientist can ignore that.

[@fatsiddog]

William Fenton I myself have a theory, Jack Horner is a scavenger as well, picking up rotten ideas when he stumbles upon them. Look at the beady, dull eyes, a feature found in all scavengers, the ugly and disheveled appearance is certainly not that of a top predator. 😎😁

[@TMH713]

I love how he is taking jabs at Horner the entire time and calling him on his bullshit. Excellent presentation.

[@marcoghiotti7153]

love how he bashes horner, whilst not even mentioning his name

[@barbarakyle5677]

Top paleontologist. I have his book on dinosaurs for all ages

[@christianfleetwood1735]

Amazing how reserved he is when talking about Tyrannosaurus. IT'S TYRANNOSAURUS!

[@lorrieharkey3383]

I’ve watched this at least 3 times and I’m still enjoy it .

[@michelfraenkel4920]

5 here. Ha

[@ShaudaySmith]

Dr. Holtz is great at presenting this info. I've seen a few of his talks and they are always entertaining and informative.

[@hornerhateblog6224]

Our champion Horner Hate Nuggets: 13:00 22:19 28:28 29:21

[@BFree-ge6ms]

Lol! And thank you!

[@The_PokeSaurus]

Some parts of this haven't aged well, but that naturally comes with paleontology. It's still worth watching.

[@Keaze]

Which parts haven't aged well?

[@The_PokeSaurus]

@@Keaze The parts with Spinosaurus (Because it's Spinosaurus) and some parts with the Tyrannosaurus.

[@CCNorse]

@@Keaze The main thing that comes to mind for me wasn’t really an issue of aging well vs just being wrong, but we’ve had integumentary impressions with T.Rex fossils since the 90s and they are scaly. Since this talk, there has been papers drawing together the description of all known Tyrannosaurid skin impressions, and the consensus is zero or nearly zero fuzz/fluff for all advanced giant tyrannosaurs, because we now have sampling from almost every part of the body from more advanced Tyranosaurids than Yutyrranus. Yutyrranus is the only “big” tyrannosaur that shows fluffy integument, so either it’s some kind of weirdo outlier in terms of integument, or it’s taxonomic position is incorrect. And Climate isn’t the explanation, similar sized advanced Tyrranosauroids from colder climates still show scaly integument.

[@shelleynobleart]

What a brilliant lecturer. So clear.

[@mralsfan6996]

Excellent! Very informative and very interesting. Dr. Holtz is a great speaker/teacher. Thank you sir for making this so interesting.

[@imhatchmantoo]

Well this is awesome 😮❤

[@mrchugs1]

Took a class with him at UMD. Hilarious and interesting!

[@blockmasterscott]

I like his presentation, I wasn't bored at all.

[@fredlandry6170]

I’m a T Rex fan. They were the badasses of North America during the Cretaceous epoch.

[@wishgodgirl1903]

Really enjoyed this lecture, all because of the lecturer. I love listening to him…

[@donaldmccann2049]

Excellent! Informative and entertaining. The light levity makes the presentation truly outstanding. I wish to see more presentations by him.

[@kylgrv]

That was an awesome lecture. I really like this guy.

[@carlhess5707]

It always amazed me how much people that study dinosaurs just make things up and present it as fact

[@catzkeet4860]

They do not “make things up” if they’re reputable scientists. They come up with one or other hypothesis, based around the available evidence. Neither they, nor anyone else currently alive, can see dinosaurs alive so all they can do is extrapolate based on morphology of fossil evidence, genetic evidence, current animals, behavioural knowledge etc. This, ofc changes with technology, new discoveries, improved sampling. If you are taking what they say as “fact” that’s more on you than them. There are some details that are as close to fact as we’re gonna get it, like feathered dinosaurs, confirmed by fossil evidence, physical sampling of that fossil evidence and clear evidence on the bones of feather attachments, but it’s still only a very good best guess(more likely, than unlikely) since we cannot “know” for sure.

[@addish5022]

Since when did they just pull things out of their ass exactly?

[@BrainBlatster]

Thank you so much for this! This definitely madey day ❤

[@BurgundyCouture]

I love him; he speaks so well. He doesn't use jargon and is so enthusiastic! He's so sexy too, haha!

[@jkutnink87]

This video didn't age well, now the Trex is the largest Theropod ever, Gigantosaurus and Carchardontosaurus have had their size adjusted and on average they were smaller than Trex. Spinosaurus is now known to mainly be next to a body of water like a crocodile, it also loved to walk on all fours and even swam. It's weight was also changed. The Spinosaurus is now known as the longest but the most massive is Trex by alot.

[@majungasaurusaaaa]

We don't know. We have far less from the other theropods. There is no knowing whether there are larger individuals out there.

[@jeffreygao3956]

No, those theropods are all of similar size; Tyrannosaurus IS however the most robust.

[@tscream80]

Boy, that Spinosaurus looks so dated these days. ^^;

[@jeffreygao3956]

I read his book at one point and it WAS AWESOME!

[@raymondminton6388]

He didn't have to give the name for us to know he was referring to paleontological crank Jack Horner.

[@CristalcatXP]

This gave me 7 good pages of notes!

[@n.j.walker8747]

An excellent lecture! I subscribed and bookmarked so that I may return to view it again later, in case I missed something and to reinforce my understanding of it. I especially like the lack of long scenes where a paleontologist bores the manure out of me while she or he hikes from one dig to the next, describing how his or her team travels to those sites. I don't want my computer chair to be covered with manure, though I would like a coprolite as a paper weight. ;-) "I hate field work!" - Brendan Fraser as Professor Trevor 'Trev' Anderson in Journey to the Center of the Earth (2008 film)

[@N0rmandy]

"There are five people in the world who can tell the difference, or care" omg haha

[@michor10]

This was amazing. Thank you!

[@RemoteViewr1]

Great public speaker, brought up new points. Great passion, funnnnny, insightful. Science is questioning.

[@Chrisfeb68]

This was good...makes me wish I was back in college again...well..without all the exams:P

[@garywhitman2540]

There are 2 complete tracks and 1 partial track on Philmont Scout Ranch, Cimarron NM.

[@THETROMBENIK]

42:00 Fuzziness has been noted in previously discovered specimens. It was noticed when reevaluated previously described samples.

[@EsotericOccultist]

This is interesting and well presented👍

[@MargoSki1959]

Dr. Holt thank you for all of your on Rex & your videos I really appreciate the information, I am a Chef 👩‍🍳 however I love dinosaurs and Native America info!!! 🇵🇱🇺🇸👩‍🍳

[@Peppermint1]

How come we are finding fissile leaves and fern but very little dinosaurs soft tissue ?

[@crystalheart9]

37:32 answered a question I had about birds being dinosaurs. When I was a kid in 6th grade in 1962 our science teacher made the statement that birds were dinosaurs. I was really stunned by that and wondered if it was true. I also wonder how she came upon that information at the time.

[@tmo4330]

Actually, birds of the air were created before any land animals.

[@catzkeet4860]

@@tmo4330 and back in the real world….

[@tmo4330]

@@catzkeet4860 Genesis chapter 1 starting with vs 20. Birds and fish were created on day 5. Land animals and man were created on day 6.

[@panchoverde5078]

This guy stats dropping wisdom bombs right out of the gate

[@kennyferry]

Awesome. So much information covered.

[@Prayukth]

Why did Panda turn vegetarian? According to a study, it may have had to do with the deactivation (technically known as “pseudogenization”) of an umami taste receptor gene. Umami is the taste that makes things like meat, soy sauce, and mushrooms extra yummy. Apparently, at some point in panda evolution, the umami receptor became non-functional.

[@jeffreygao3956]

If this is how he performs lectures, then I wonder how his book is.

[@UglyKidMetallica81]

He was all over the place. Constantly interrupting himself.

[@LolSnimci]

UglyKidMetallica81 i dont see any problem

[@robertgolden1080]

Awesome speech for a fantastic animal.

[@laara1426]

So sad your peer still believes that T Rex are only carion eaters. Sounds like he or she read the same book I did when I was 7.

[@OakenTome]

He might've even had a hand in writing that book!

[@seandraco3797]

I like the 100% hypothetical idea of arm feathers. They have a wolf's senses so it fits for a pack animal. I kinda like the idea of "dinosaur birds of paradise". Can't imagine much lower body camo at tree size helping. Blending the back/top into your surroundings... maybe but it's like hiding a tank haha! But that lower body could be display, sex indication, health, age. (Cool for drawing BTW)

[@kyle857]

A new study on Stego puts their hind legs as shorter than we originally thought.

[@jsfbr]

Excellent!

[@MWK1995]

so t-rex is the king afterall

[@andythegoatman694]

Goin after horner like a damn savage

[@robbie_]

Very interesting talk. Thanks for sharing.

[@thememoryhole9355]

20:22 .. Could this be like the difference between alligators and crocodiles?

[@RealBelisariusCawl]

0:28 I’m not alone! My answer to the “what do you want to be when you grow up” question circa age 5 was unerringly “a Tyrannosaurus rex!” Followed by my best attempt at a roar.

[@Jurassicparkatmospheres]

4:11 scared the shit out of me

[@lukeskywalkerjediknight2.013]

Lol

[@geekfreak41]

Im from london and would love to meet him in maryland!

[@michealtaylor7745]

Why only Maryland? Wouldn't you like to meet him in London too? UK

[@frlade]

Great show!! :)

[@mdhbigdog]

I'm enjoying his book, "Dinosaurs: The Most Complete, Up-to-Date, Encyclopedia for Dinosaur Lovers of All Ages," with excellent illustrations by Luis Rey.

[@robertredbeard1855]

Anyone who thinks gizzards are for only seed eaters, has never watch a group of chickens go zombie apocalypse on a rat or mouse.

[@xs5283]

43:00 What is that screaming???

[@synthWizkid]

11:55 i thought tyranosaurs were found almost globally.

[@tyrannotherium7873]

It’s actually implied at Tyrannosaurus rex is now the largest theropod interms of muscle mass and weight

[@jimgoodman1845]

Applause Applause.

[@lifeofkyle]

I am asking for a lot of questions about T Rex

[@deckprofiles-ptcgoandmorea9353]

I have a question: how come your mum only charges 55 cents a ride these days?

[@alisalundh4056]

Yaaaay Thomas Holtz! XD

[@Scoobydcs]

t rex arms are vestigial (or on the way) like the legs on whales??

[@thememoryhole9355]

53:45 .. Are there any warm blooded reptiles today? I do know about the Tegus from S. America. Also, birds are closely related to reptiles and are warm blooded.

[@StormsandSaugeye]

Birds fall firmly into Reptilia

[@MrJonnyPepper]

I think maybe T-Rex was the persistence Hunter. It might not have been able to run fast but it could out endure what it was after. It would Chase things for days similar to early human Hunters. Just an idea

[@marcellepesek3038]

You have a good point. I always wondered about a huge animal like T-Rex running at speed, although he had his large tail to balance him, but what if he were to fall down? Would he be able to get up using his tail? His front legs were useless for that. He may easily have just worn down exhausted prey.

[@adreabrooks11]

I've had a similar hypothesis. Metrics seem to show that T-rex was evolving steadily away from running and toward walking. Those serrated teeth would be breeding grounds for bacteria - and I always wondered if tyrannosaurs might not have hunted like komodo dragons - biting a big scoop of flesh out of its prey, then backing off; following at a distance while infection and blood loss worked their magic, and using that colossal olfactory sense to follow along at a stoic pace. When the prey item finally dropped, those big bone-crusher teeth would make the most of every bit available. The fused nasal bones and otherwise robust skull would work well for a "chomp and tug" attack, as would the anchor points on the neck. The overall build supports a dogged endurance hunter and so on. Of course, I'm just a lay-person (albeit an avid student of biology) - but the concept so far seems sound. I'd be interested to see an in-depth examination by the pros in this regard.

[@Karagianis]

If a name is given to a new specemin in error and it turns out just to have been something already discovered and the name is discontinued. Can that name then be reused for something else later?

[@OakenTome]

It unfortunately cannot :[

[@dwightehowell6062]

Jane and Bloody Mary appear to be Nano Tyrannosaurus. Either that or Juvenal T-Rex hunted in packs with their peers and had larger forearms than adult T-Rex.

[@tanehickey9887]

Dwight E Howell nanotyranus is proven to be a juvenile trex jack horner cut open the bones and found juvenile bone tissue and compared it to the trex its 100% trex

[@krabkrusttv2930]

Guess dryptosaurus was screwed if T.rex made it across Appalachia.

[@kyle857]

Toro has a smaller body than a triceratops. So I find it unlikely it would be the mature form.

[@AaaaNinja]

The debate is over, it's a different species because they've identified juveniles of both species, which wouldn't be the case if they were indeed just different life stages of the same dino. I don't think that going by body size is a useful a parameter to go by because there can be size differences between individuals.

[@jaw2k6]

The greatest professor OF EVER!!! #church

[@dwightehowell8179]

At the triceratops kill site where Bloody Mary was found 36 shed teeth of similar sized animals were found. Since no teeth of larger animals were found and Bloody Mary, Jane and Nano tyrannosaurus are all the same size that is suggestive. Bloody Mary also has larger forelimbs than an adult tyrannosaurus. The actual forelimbs of the others are not known.

[@nyoodmono4681]

The younger they are the more agile they hunt. With age their brain and with it their olfaction grew. As Adults they tend towards scavageing. Could that be true?

[@OakenTome]

Unlikely. They're still built for hunting as adults, just different prey from when it was young.

[@nyoodmono4681]

@@OakenTome Because of the alinement of their eyes? Why "unlikely"? I find it unlikely that they were able to lur and suprise attack with their size. It could be that they were specialized on sauropods, because anything lighter is too evasive. The question is how were they able to make sharp turns at high speed and how did they manage to not brake their bones whenever they stumble?

[@dedewahyudin1074]

How long t-rex from head until tail?

[@JaydenDimaio]

Dede Wahyudin 42ft

[@optimusprime8543]

Either 40 or 43 feet in length

[@dalerose3500]

Hypothetical question. If a T-Rex was able to be cloned, wouldn't it grow smaller than it was in the Cretaceous period due to lower oxygen levels today compared to the Mesozoic era? I would think a Tyrannosaur in its original size would have trouble breathing and able to function without ample oxygen to fuel the muscles.

[@jeffreygao3956]

No, the oxygen levels in the Mesozoic were about the same. The main issue would be feeding the darn thing!

[@dalerose3500]

@@jeffreygao3956 Actually the O2 level was estimated to be around 30 percent during the Cretaceous period, 10 percent more than today.

[@jeffreygao3956]

@@dalerose3500 I did not expect that.

[@Indy44636]

horner you taking notes , { gignotasaurus isnt an allosaur we cane tell that due to size and the skull shape as we as the bumps on the skull which isnt a trait seen in allosaurs .In terms of weigh t rex is still the largest theropod , while in length that would be spinosaurus .

[@WarDaddy66]

What if Trex gave live birth? Is there evidents of eggs?

[@jeffreygao3956]

1. Phylogenetic bracketing from birds and crocodiles says no. 2. Sure. Ask B-rex. She had medullary tissue meaning she was brooding.

[@Titus-as-the-Roman]

A T-Rex and a big, strong alpha Grizzly Bear are two totally different creatures with a superior sense of smell, I believe they both held a very similar place in their respective habitats. A big Grizzly will rarely pass up the chance to chase off a smaller predator from it's kill or other carrion it came across, it also will not hesitate to go after it's own game if hungry enough and the situation is right. T-Rex most likely had a similar strategy. Dr. Horner is most likely correct in part, but not all the parts. I like and respect him for his lifetime of brilliant work, I wish he could amend his theories, I really would feel bad if some sort of evidence came to light that showed him wrong, with today's media he would be hard boiled by his adversaries and all his other great work would become a back drop.

[@WhiteMetalNinja]

cool!

[@mathewkolakwsk]

Science is indeed much more than a body of knowledge… but like 1 minute after that detail about science is stated, he reminds us that our species is not “homo sapian” but rather “homo sapians”. I mention this because knowledge/facts/memorizing details is absolutely central to being a scientist, in part because it can be thought of as a language. At any level, educators shouldn’t dismiss the fact that knowing things is essential for understanding how these things connect…too many educators are omitting knowledge for so-called skills based learning (but you can’t get to the higher order stuff without having a strong/solid lower order knowledge base to build upon!). So keep learning those facts kiddos! The more time you spend with those facts, the more they sink in - and then when you apply those facts by making connections, you’ll never ever forget (whatever topic you’re learning about!)

[@mikepug1]

Brilliant many thanks

[@samuelelder9434]

Apparently, T rex had a bunch of bones.. who knew!

[@richardevppro3980]

Talking about T-rex realy does make me feel it scavenged more than hunted, look at the size of its brain used to mell it's massive compared with similar meat-eaters

[@jasonvoorhees5180]

Using its increased olfactory acuity to argue that it scavenged more than it hunted is a rather fallible idea and doesn’t even really hold true for modern carnivores mainly because that trait alone is not synonymous with scavenging behavior (see albatross, sharks, crocodilians etc). All that does is tell us that it had a keen sense of smell which could be used to more effectively detect odors from long distances with greater precision. All of T.rex’s senses are just characteristics that make it an efficient killing machine, the fact that some of them would also aid in the process of opportunistic scavenging is just a side effect of those traits not the cause (that and heightened olfaction can come about for more than one reason and be used for more than one purpose) There is no reason to believe that the animal scavenged _more_ than it hunted for prey, it would’ve required too much food regularly to rely on such foraging behavior. Other large theropods relied on some attributes more than others to hunt with larger portions of their brains being geared toward other sensory functions in comparison to T.rex (that or their brains were relatively smaller in relation to their bodies altogether), that’s not indicative of the latter being more dedicated to detecting carcasses it’s just an example of coelurosaur divergence in evolutionary paths from other large Avetheropods. anatomypubs.onlinelibrary.wiley.com/doi/full/10.1002/ar.20983 There’s also fact that relatively large olfactory lobes are actually pretty widespread in non avian dinosaurs particularly theropods, sauropods and even ornithischians like hadrosaurs and Thyreophorans even if its more pronounced in T.rex itself than others ia601002.us.archive.org/24/items/tyrannosauridpaleobiology2013/J.M.%20Parrish%20%26%20al.%202013%20-%20Tyrannosaurid%20paleobiology.pdf books.google.com/books/about/Tyrannosaurus_Rex_the_Tyrant_King.html?id=5WH9RnfKco4C books.google.com/books/about/Acrocanthosaurus_Inside_and_Out.html?id=-QoXDQAAQBAJ

[@Sfhakrn]

Tyranasaurus has been found on 5 continents including Antarctica and possibly Australia.

[@Superchilliface]

Any Young Earthers here? NO? I didn't think so....

[@Blandina11]

Sometimes even the "Flat earthers" arrive in these threads. 🤣😂

[@nelsonparsifalcantebury5083]

By modern estimates, the giant allosaurs didn't have the weight or bite strength of Tyrannosaurus. The only large carnivorous dinosaurs that may have outweighed T-Rex was Spinosaurus.

[@KurNorock]

Justin Weinzierl spino estimates are vastly overestimated. They basically took large Theropod weight and scaled it up to a 50 foot animal. But spino had a much different body structure being very slim and not nearly as heavily muscled as other large theropods, and much smaller limbs and a much lighter head. A reasonable estimate would be 5 to 8 tons. Meanwhile, estimates for the weight of Rex traditionally have been too conservative. More recent findings suggest that Sue would have weighed between 8 and 12 tons.

[@KurNorock]

Jesse Hoffman that's is some of the worst arm chair logic I've ever heard. What would a scavenger need with the bifurcation bite force of any land animal ever? And while the teeth were blunt, that shouldn't lead you to believe they weren't dangerous. They aren't meant to be slicing tools, they are crushing tools. Trex gives by crushing the bones of its prey to cripple and kill it. That's why it's bite force is so high. If it had traditional thin sharp teeth, they would constantly break off under the tremendous bite forces. The tiny arms aren't a weakness. They are the result of the enormous and powerful jaws. There is only so much real estate for muscle attachment. You have to choose, big arms, or a big head, and if you choose big head, you need a thick and powerful neck, which Rex had and those breech muscles take up all the room leaving very little for shoulder muscle attachments. And even those tiny and weren't useless. They had somewhat large claws and could exert hundreds, if not thousands, of pounds of force. I do doubt that trex hunted adult triceratops all the time. Like any other apex predator it would have target young, sick, or old animals to reduce the risk of personal injury. But some rexs, especially the larger ones, may have specialized in hunting large adult trikes just as some lions specialize in hunting large adult water buffalo out giraffes. Also, scavengers don't need binocular vision. Especially when they have the best sense of smell that ever existed. Binocular vision is a hallmark of a primarily predatory animal. Of course trex scavenged. All predators do. But it primarily hunted. It is built for it. It is built to follow herds of pretty animals around, single one out, and kill or cripple it with one bite, likely holding on and dragging it to the ground. There is direct evidence that trex would pull the heads of off trikes in order to have easy access to the thick neck muscles.

[@KurNorock]

Jesse Hoffman hyenas hunt regularly. That by itself completely defeats your argument. Find me a single example of an animal with a large bite force that is a 100% pure scavenger and I will conned that your argument might have some merit. As far as the trex pulling the heads off of trikes.. www.nature.com/news/how-to-eat-a-triceratops-1.11650 Your personal incredulity is not evidence. That means, just because you personally can't imagine something, doesn't mean it can't be true. And a lion pulling the head off a rhino is nowhere near the same thing. First, lions have relatively weak bite force for their size. Tigers have a bite force almost twice as strong. Also, a lion is less that 1/4 the size of a rhino. An adult Trex likely outweighed an adult triceratops by several tons. Also keep in mind that it wasn't just the trex jaws that were over developed. The entire animal was more heavily muscled than any other dinosaur. What was it doing with all of that excess strength of it wasn't pulling the heads off of its prey?

[@peccantis]

I can't unhear Kermit whenever he says "meat eaters".

[@TITANSofTheEARTH]

This was ...1houre pure knowledgle! THX 1h TV documentary...5min already known knowledge and 55min shitty animated wrong action scenes...

[@nachodorito6955]

The reason they died wasn’t from impact most individuals couldn’t smell with naval cavities clogged by soot which was crucial for them to hunt or scavenge. They basically were blind and couldn’t smell anything for 15 years and starved.

[@OakenTome]

A simpler explanation is that the species they hunted lost the plant food sources they relied on due to the change in atmosphere, and thus t-rex lost its food source.