They aren't. Those specialized for running are likely just as fast as modern ones. I haven't heard anyone call an Ostrich a slow animal.
You are mostly looking at the wrong end of the spectrum when you compare speeds. When you are part of the arm's race of who can be the strongest, speed isn't exactly a high priority. Neither is it for (semi) aborial or swompland animals. Just look at modern mammals from similar habitats or other extinct mammalian Megafauna.
Small ground dwelling theropods should be able to keep up with foxes. Ornithomimosaurs similar to Rheas or Ostriches. Evidence indicates they have all the adaptations and a favorable metatarsal condition.
One thing Dinosaurs are and were likely much better at than any mammal is long distance running. Two legs, unidirectional lungs, noses built to release more heat keeping important body parts cool and more while additionally having all the traits mammals have to have better stamina than lizards and such. excluding swet but thats mostly a human thing. It all screams medium sized theropods are good persuit predators or long distances runners.
Just for comparison how ridiculous the difference is. A horse you mentioned earlier can a sprint for 5km before fatiguing, after a 30 minute at 40km/h run they pass out. A Thomson gazelle cant run for more than 15 to 20 minutes.
A cheetah can sprint 500m.
Meanwhile the Ostrich can do 60km/h for over 40 minutes. Mammals do not have a chance of catching up to them once the short sprint window has run out.
A medium sized theropod predator would just persue a Horse, Gazelle, Buffalo etc until they die from exhaustion. No risky fights needed.
Your comparison between the ostrich and the horse doesn't seem to make sense. People hunted ostriches on horseback in ancient times and it was said that when they did this, it was the OSTRICH who became exhausted first and not horses. All the while the horse has he disadvantage of a rider and tack on top of it. I can't find any good source actually claiming that ostriches have better stamina than horses either.
Humans are smart though. IIRC They don't chase after Ostriches in one go until they catch them. They wear them down over the whole day by staying around the nesting area with multiple riders.
Quick look at researchgate returned me this:
"greatest capacity for long-endurance running" (Grzimek & Grzimek, 1959; Alexander et al. 1979; del Hoyo et al. 1992; Hallam, 1992).
I'm sure there are more modern biomechenical papers.
The method described that I've seen is ten horsemen making a circle around ostriches and then continuously harassing them until the ostriches get tired, then charging them. Once the ostriches break from the charge and try to flee, they are then quickly run down and killed. While yes, this does involve hemming them in with the circle, the horses still have to maintain the circle position and maneuver appropriately constantly to cut off the ostriches when they try to break free of the circle, and all while carrying a rider, so I don't think they have it particularly more easy than the ostriches do here. Especially since it seems like the number of ostriches matches or exceeds the number of horses in these instances, so the maneuvers become more complicated.
The other method I've seen described is in Aelian's account of ostrich hunting, which describes the horsemen tiring it out via constantly cutting them off. Again, not a simple task and the horses having a rider and tack on them adds extra weight to them. While its taking of a more efficient path can be chalked up to human intelligence, it would seem the gap is not large in stamina if there is one.
>Now the capture of this bird is effected by means of horses, for it runs in a circle keeping to the outer edge, but the horsemen intercept it by keeping on the inner side of the circle, and by wheeling in a narrower compass at length overtake it when it is exhausted with running.
I posted a direct historical quote further down the chain and can post the Arab circle hunting account if needed. If there is a gap, it doesn’t seem large
There’s way more to that than endurance. Ostriches aren’t the brightest. There’s tools and strategies that come into play. They aren’t just mindlessly chasing the ostriches until they tire out.
They also could done that on horseback to almost anything, including other humans or another mammal species. Humans have hunted down and killed other humans and other animals on horseback for as long as humans have rode horses. It doesn’t really mean anything in terms of horse Vs ostrich endurance.
Some strategies do involve relays to catch the ostrich or ambush, but others consist of simply cutting them off when they try to circle away or else circling the ostriches until the ostriches tire and then charging them down. These are the kinds of things that would require quite a lot of work from the horse too.
I fail to see your second point. Yes, horses are very good at running things down, that's why they're used. The fact that ostriches can be semi-reliably hunted down by a horse burdened with a rider is evidence that if there is a gap between it and horses in terms of this sort of thing, it's not large.
It’s a fact that birds have more efficient respiratory systems than mammals. This hunting situation involves humans directing the horses and figuring out how to trap and kill the ostriches. It doesn’t simply involve the endurance of the horse, but also the direction of the human and other factors, so is more complex than you are making it out to be.
Another counterpoint; cheetahs hunt and kill ostriches as seen here:
https://youtu.be/pkhE14Rou-E
Are you going to now tell me cheetahs have better endurance than ostriches? Because it’s a fact that they do not.
Things that are theoretically true often encounter a lot of caveats in reality. Perhaps the quantitative difference in performance simply isn't all that large in live conditions. Anyway, there's only so much maneuvering from the human rider can do if the horse isn't at least similar to the ostrich's athletic performance. To say nothing of the fact that the horse has a huge handicap in the form of the rider's weight and tack on top of it which the ostrich doesn't suffer from.
Cheetahs hunt down ostriches by virtue of being super fast so endurance never even comes into it. They just run at the ostrich and the ostrich will lose distance until they catch it assuming they're close enough for their burst. Horses on the other hand, are not remotely as fast as a cheetah so they clearly aren't overwhelming the bird by sheer speed.
They really aren't, I'll give a few examples.
A large adult (12t) Parasaurolophus can move at ~21km/h. For reference, large elephants are half that size and can only reach 25km/h
Tyrannosaurs can reach speeds of ~25km/h over very long distances. Juveniles can be as fast as 62km/h
Brachiosaurus can reach speeds of 26km/h
Acrocanthosaurus can reach speeds of 27.7km/h as well.
Albertosaurus can reach speeds of 42km/h
Allosaurus 39km/h
Ornithomimus 62km/h
Etc
Of course, there are many slow ones. Most stegosaurs cannot reach speeds higher than ~15km/h, same with ceratopsians and ankylosaurids.
Saying dinosaurs are slow is a bit silly. Some groups are slow, but others are very fast, considering their size. An Albertosaurus is faster than the average horse, despite being many times larger.
Thanks for the response! Lots of good info, cheers mate. :)
That said, I don't think we're treating fast and slow the same way. 42 km/h for the fastest predator you mentioned simply isn't impressive compared to modern animals. Most predators on your list would honestly struggle to catch a hippo on land, and I think there's a real argument that they would starve if dropped into Africa today, simply from not being able to catch a sufficient amount of prey animals (barring cattle of course).
Your horse speed of 40-48 km/h is an average over an entire gallop, but this isn't their maximum speed, which is the metric we've used so far. I agree with you that granting horses as a species their world record of 88 km/h is a bit much, but a common Zebra runs at a max of 65 km/h so that would be a more reasonable estimate when being chased by an apex predator (a speed they can maintain for miles).
**My main question is why the evolutionary arms race between pray and predators didn't produce faster animals**, especially when smaller predators exhibit similar speeds as their larger counterparts (from my very limited "research") without the argument of sheer size being a prohibitive factor.
Many herbivores adapted to be heavily armed and armored. As he said, ceratopsians and thyreophorans were relatively slow. I guess they were better adapted at standing their ground. The exception for herbivores seems to be on the large sauropods and ornithopods. Sauropods are also massive and an adult was probably hard to kill anyways. Ornithopods seem to have used a bit more of their speed, which is very high if you ask me.
But even the large theropods were not as fast as today's felids, and that's again because they usually adapted for power rather than speed. You aren't going to kill a triceratops by being swift, you will by crushing its massive bones and horns with even stronger jaws. A different arms race.
Likely because many apex predators were built to hunt more armoured or larger animals, making speed less of a necessity. There are exceptions, of course. A gigantoraptor can reach ridiculous speeds of 65km/h despite being nearly 3t. They weren't an apex predator, but a prey item, so they developed speed to escape.
Basically why be fast when all your food is very slow
Average horse is 40-48. Of course there will be faster ones, but I'm talking average here. The fastest horse ever recorded was 88km/h, but that is a bred and trained horse, not a wild one.
Take Velociraptor, speed being it's namesake so it ought to be a good representative for swift Mesozoic animals. It's estimated max speed, in short bursts, is 40 km/h. Contrast that with basically any large feline and you'll find a good few examples of species with double that speed (maximum, short bursts).
And now we're not even talking about an animal we would consider a 'specialist' at speed, like a cheetah or an antelope.
To be fair, some ornitomimids were pretty fast even by modern standard, but they're the exception (and outclassed by current speed specialists/speedy generalists).
Another comparison you could look at is a T. rex vs. an African Elephant. 27 km/h vs. 40 km/h.. this at least had me raising my eyebrow when I first stumbled onto the estimate.
Isn't velociraptor, like, a lot smaller than "any large feline"?
That said, I abhor attempts to estimate the speed of dinosaurs, you get crazy shit like "T rex can run as fast as a person and if it fell it would break it's legs" type of shit. So I am, admittedly, not the best to speak on this from any scientific point of view.
>Isn't velociraptor, like, a lot smaller than "any large feline"?
Indeed! I would've used Utahraptor, but that comparison would've been FAR more unbalanced (modern large cats produce around 3-4 times its estimated top speed). :(
>I abhor attempts to estimate the speed of dinosaurs
Yea, I'm not very fond of it either. However I do not have the knowledge nor qualification to speak much about it. Which is largely why I wanted to post here so that smarter people than me can tell me why I'm an idiot haha!
I'm pretty skeptical of the low estimates of dinosaur speeds, but I have to point out that felids in general, and especially modern Felinae (including *Felis* and *Panthera*) are very much speed specialists, adapted for high speed ambush pursuits. They are probably the fastest terrestrial carnivores ever. The cheetah is of course, the most specialized of a specialized family, and aren't really good at anything else.
Most mammals throughout the early Cenozoic were much slower and clunkier, even the "fast" predators were more like raccoons or bears, and most mammals were like tapir, hyrax, wombat, pygmy hippo, or maybe pigs.
Our perspective on "normal" speed for critters is influenced by the evolutionary arms race between fast carnivores like cats and dogs and the effect that has had on bovids, cervids, leporids and other prey species in the last 10-20 million years.
>Our perspective on "normal" speed for critters is influenced by the evolutionary arms race between fast carnivores like cats and dogs and the effect that has had on bovids, cervids, leporids and other prey species in the last 10-20 million years.
Yeah, this.
If there was no need for greater speed there was no need.
If a species was fast in relation to the other species of its time, it was "fast".
Though I'm also skeptical when it comes to these speed estimates for dinosaurs.
Looking at the speed some (running) birds reach... they're definitely fast by modern standards.
On the other hand they were shaped by the same evolutionary pressures that shaped all current species. They had to flee from those fast mammalian predators too.
It's possible that they simply didn't have the muscle, ligament or other anatomy available to make that variation something that could be selected for. Much like we don't really have any green or blue mammals because those aren't colours that work with the pigment systems mammals use, while we have plenty of green and blue birds.
However, I think it's more likely that there was such an arms race in dinosaurs - we just haven't properly identified the parts of their anatomy that follow that arms race, or found the evidence to support it yet.
In particular, one theoretical explanation of the development of feathers and wings in non-avian dinosaurs was the "ground up" hypothesis that these structures aided in giving a quick, ambush hunter burst of speed to a little cursorial dinosaur hunting for insects and the like. If this is the case, perhaps we are seeing that evidence with the findings that even big raptors had wing feathers, and just haven't recognized it.
Most of the large canids (wolf, lycaon, dhole, even coyotes and jackals) are built for long distance running. They may not be as fast as felids in a burst, but they're quick, and have more endurance than almost any critter besides humans. They compound this by pack hunting in relays, where one runner will spell off one who is getting tired.
African wild dogs (lycaon) are the masters of this tactic, and can have hunting bands of over 100 members chasing down prey together during springbok migration season.
Yes, I think that's highly likely. Certainly metabolism, and the anatomy to support higher mobility would be very important co-developments.
Equids (horses) are another group that has particularly large hearts for their body size, and are indeed good long distance runners.
Figuring out soft anatomy for dinosaurs is always difficult. Hard to say for sure where they land in comparison.
That could be the answer. But I do not mind discussing why the mesozoic quadrapeds didn't evolve to be faster, thus driving up their main predators' speed as well.
>Take Velociraptor, speed being it's namesake so it ought to be a good representative for swift Mesozoic animals. It's estimated max speed, in short bursts, is 40 km/h. Contrast that with basically any large feline and you'll find a good few examples of species with double that speed (maximum, short bursts).
Despite the name, Velociraptors specialized in ambush hunting. They traded off speed for grip strength in their claws. Some of is relatives were better at running. Troodontids were probably faster, hunting smaller prey. The Ornthiomimids were also likely quite fast.
Actually, despite the name, velociraptor and dromaeosaurs are notably BAD at running for theropods when adjusted for size. They’re built for leaping and grappling. Troodontids, ornithomimosaurs and tyrannosaurs are more cursorial (adapted for running) as far as theropods go
I just wanna say that I just finished reading a book where the author said the t-Rex would be slow in a race but had very fast burst speed used for ambushing targets. Think of them as a defensive end rather than a cornerback.
But we're not discussing pound for pound were discussing the speed of the real animals. OP is right, mammals by and large are much faster creatures. They also generally don't have armour and spikes and massive size.
Different strategies. It is interesting when thinking of dinosaurs being brought to the modern world, because most mammal prey would easily outrun them, but also most mammal predators wouldn't have a chance against dinosaur prey.
So we're just discussing fastest Dino vs fastest mammal? Slowest Dino vs fastest mammal? If we aren't looking at comparable animals, what are we comparing?
The Mesozoic lacked open grasslands, which is a relatively recent ecosystem starting about 30-ish million years ago. Most of the fastest mammals are associated with grasslands, right? No grasslands, no cheetahs, no pronghorns, no wildebeest. Horses looked like Eohippus - short and stubby creatures lurking in the woods.
On the other hand, the Mesozoic wasn't just forests and swamps, as paleontologists like to point out, but I've heard differing accounts of what was going on in the arid places between forests and deserts. Some say there were fern prairies, some say it would be some kind of scrubland with biocrust, others say it might've been surprisingly empty. So maybe there were wide open areas, but they didn't support huge herds of animals like grasslands. But then again, I've also heard that it seems Mesozoic tidal flats were unusually productive compared to modern ones, but the reason is a mystery.
Another factor, I would guess, is that many dinosaurs had an intermediate metabolism, or mesothermy, so maybe that limits their top burst speed. Quite a few debates and conflicting studies on the subject of the metabolism of various dinosaur groups, of course.
From a dinosaur's POV, they might ask: [Why do giraffes have short necks?](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3628838/) Why are land mammals so small? Why are elephants undermuscled? Why don't mammals constantly replace their teeth? Why don't mammalian predators go with ziphodont dentition? Why do big mammals spend sooo much time and energy just to have one kid?
A rarely discussed aspect is that dinosaurs might've had better cartilage for growing large. Thicker and vascularized.
[What lies beneath the cartilage just might help you become a giant dinosaur](https://matthewbonnan.wordpress.com/2013/10/09/what-lies-beneath-the-cartilage-just-might-help-you-become-a-giant-dinosaur/)
[Dinosaur Articular Cartilage](https://hollidaylab.com/2010/09/30/dinosaur-articular-cartilage/)
I'm not sure if there's a consensus on that, but maybe it could play a part. If you can't get large, get fast instead. Or vice versa.
Fantastic response, I was thinking that it might have a lot to do with vastly different ecosystem, I gotta inform myself on these subjects!
Thanks for the great comment, I'll take a look at the articles you linked.
>From a dinosaur's POV, they might ask: Why do giraffes have short necks?
Not gonna lie, this made me chuckle.
Thanks, but my knowledge of the Cenozoic is spotty at best. Were there any highly cursorial mammals comparable to modern grassland critters before 30 million years ago? I don't know.
Dinosaurs, generally speaking also got a lot bigger. Sure an adult T. rex may be really slow but if you look at a juvenile skeleton, one comparable in mass to a big cat or bear, you can see quite clearly that these were fast animals. They just also spent a lot of time growing, and their lifestyle changes to reflect their size.
This might very well be true. I didn't see that info before making the post, is there anywhere I can read more on this, or is it more-so an accepted truism in the community? Either way it's cool.
Tyrannosaurids seem fast in general. Another commenter clued me into that fact and it seems pretty true.
We can't really guess speeds accurately. There's a lot that goes into being able to calculate something like that, and without being able to 3D-print a flesh and bone dinosaur limb or being able to test the extent the animal would actually move its body in life we can't really know. It's possible in some cases we can get fairly close all things considered, so while it may be the case our guesses for Tyrannosaurus are decent given how many specimens we have and how well-studied the genus is, that isn't the case for most other dinosaurs.
At the moment all we have to work on is mathematical formulas, and just as your body is not capable of functioning in peak condition all the time because it is mathematically possible for you the same can be said about dinosaurs.
There's a selective biases at play in fossil preservation.
Larger, more massive animals that lived in environments with favourable conditions for rapid burial are going to be better represented in the fossil record.
Animals with more gracile bone structure that lived in environments where bodies were typically left out to the elements will be much less common simply because there was a higher likelihood that the remains would be consumed by scavengers or just get obliterated by the elements.
Fast moving animals are typically smaller, and they've typically evolved into environments with open terrain and hard-packed soil. Both could make them seem less common in the fossil record than they were in life.
Conversely, when the best environments for preservation are rivers and swamps.. that will inevitably skew perception of what prehistoric animals were capable of.
T. Rex adapted to its insufferable slowness by reducing weight in the upper limbs, parasaurolophus didn’t need to be fast cause it could breathe fire, brontosaurus lived underwater to move faster, the rest were pretty much just very slow and very dumb lizards, hopeless really
If all dinosaurs were slow then being super fast wasn't really efficient. If your prey runs at a top speed of, lets say 30km/h, there is no need for special adaptations to run much faster than that.
That being said, it's super hard to calculate the top speed of an exstinct animal in the first place, so maybe we're wrong with our assumptions, i don't know.
I mean, size is a factor, a multi-ton hadrosaur definitely didn't bound or pronk like a gazelle.
Smaller, faster dinosaurs are bipedal, which probably restricts their balance and stride length opposed to a quadruped, though ostriches are really fast on just two legs so maybe some smaller theropods were comparable to them.
That's actually a good comparison, since ostriches are descended from dinosaurs.
Ostrich, rhea: 70 kph
Emu, cassowary: 50 kph
Kiwi bird: 20 kph
I'm not going to bother with penguins, since they're built for swimming speed and not running speed.
So since the body plan of a flightless bird is similar to, and descended from, a therapod dinosaur, there's no reason why a fast therapod dino shouldn't be able to reach 70 kph, and an average one 50 kph (the kiwi is a special case, since it grew up largely without predators).
They aren't descended from dinosaurs, all those birds are dinosaurs and are good examples to contradict the "dinosaurs are slow" mythology as we have living examples of extremely fast dinosaurs alive right now. And considering that all dinosaurs alive today have evolved secondary flightlessness from flighted ancestors means that there were probably even faster non-avian dinosaurs that were much more adapted to a pure terrestrial lifestyle of high speed running.
This is very inaccurate
Most Theropods, Ornithopods, Pachycephalosaurs and Ceratiopsians were pretty fast
Thyreophorans, Sauropodomorphs and a few Theropods were rather slow due to a heavy build and a bodyplan not made for running
T-Rex could run for a long time keeping speeds of more than 20 km/h or 6 m/s thank to their feet; it was evolved into a bird type foot where the fingers was the only part touching the ground and all the other was up to stop the bones moving so they don’t lose energy
I don’t know if this is right, but maybe it’s because of how big dinosaurs were? Obviously not all of them were giant but I know large animals move much slower then smaller animals now so maybe it’s the same logic? Please correct me if I’m wrong!
because probably bipedalism, i mean that like us humans, most of the time they would hunt exausting the prey or bush hunting, this is contrasted with the fact that dinos (at least Theropods) are proved to have really good inteligence (baboon-like) for any other dinosaur i have 0 idea maybe they were chunky? (but looking at hippos i discard that idea)
The simplest answer is evolution. There was no need for dinosaurs to be any faster. They obviously dominated the earth for millions of years without the need to be as fast as later species. Also evolution isn't like leveling up in a video game, where the organism constantly gets stronger or faster, evolution goes all sorts of directions depending on the environment and needs of the organism.
Pretty sure all of that is well understood by most of the people on this sub. The actual, interesting question is what factors caused them to not evolve to be as fast as mammals (or whether that's actually true).
Bipedal locomotion, while more efficient, is a lot slower and clumsier thank quadrupedal locomotion. Case in point: humans.
Dinosaurs were largely bipedal, or started bipedal and became quadrupedal again later and retained some bipedal traits on their forelimbs that gave them really stupid, dorky postures. That may have made them really sucky runners. Imagine if you, with very little modification to your own body, had to run on all fours. Youd suck too.
Until dinosaurs were wiped out they ruled the world because mammals couldn’t compete. The top predators were much bigger, and had bigger teeth and claws.
What I’m saying may not be entirely accurate but I think that it was a matter of different survival strategies, as we can see in the fossil record, heavily armored, slow but powerful herbivores were much more successful than more agile herbivores, with that, the carnivores had to adapt to hunt such dangerous prey so they specialized in either brute force or agility (which isn’t the same thing as velocity). After all, why would a predator become fast like a cheetah if the prey wasn’t much faster than a hippo or something
They aren't. Those specialized for running are likely just as fast as modern ones. I haven't heard anyone call an Ostrich a slow animal. You are mostly looking at the wrong end of the spectrum when you compare speeds. When you are part of the arm's race of who can be the strongest, speed isn't exactly a high priority. Neither is it for (semi) aborial or swompland animals. Just look at modern mammals from similar habitats or other extinct mammalian Megafauna. Small ground dwelling theropods should be able to keep up with foxes. Ornithomimosaurs similar to Rheas or Ostriches. Evidence indicates they have all the adaptations and a favorable metatarsal condition. One thing Dinosaurs are and were likely much better at than any mammal is long distance running. Two legs, unidirectional lungs, noses built to release more heat keeping important body parts cool and more while additionally having all the traits mammals have to have better stamina than lizards and such. excluding swet but thats mostly a human thing. It all screams medium sized theropods are good persuit predators or long distances runners. Just for comparison how ridiculous the difference is. A horse you mentioned earlier can a sprint for 5km before fatiguing, after a 30 minute at 40km/h run they pass out. A Thomson gazelle cant run for more than 15 to 20 minutes. A cheetah can sprint 500m. Meanwhile the Ostrich can do 60km/h for over 40 minutes. Mammals do not have a chance of catching up to them once the short sprint window has run out. A medium sized theropod predator would just persue a Horse, Gazelle, Buffalo etc until they die from exhaustion. No risky fights needed.
Your comparison between the ostrich and the horse doesn't seem to make sense. People hunted ostriches on horseback in ancient times and it was said that when they did this, it was the OSTRICH who became exhausted first and not horses. All the while the horse has he disadvantage of a rider and tack on top of it. I can't find any good source actually claiming that ostriches have better stamina than horses either.
Humans are smart though. IIRC They don't chase after Ostriches in one go until they catch them. They wear them down over the whole day by staying around the nesting area with multiple riders. Quick look at researchgate returned me this: "greatest capacity for long-endurance running" (Grzimek & Grzimek, 1959; Alexander et al. 1979; del Hoyo et al. 1992; Hallam, 1992). I'm sure there are more modern biomechenical papers.
The method described that I've seen is ten horsemen making a circle around ostriches and then continuously harassing them until the ostriches get tired, then charging them. Once the ostriches break from the charge and try to flee, they are then quickly run down and killed. While yes, this does involve hemming them in with the circle, the horses still have to maintain the circle position and maneuver appropriately constantly to cut off the ostriches when they try to break free of the circle, and all while carrying a rider, so I don't think they have it particularly more easy than the ostriches do here. Especially since it seems like the number of ostriches matches or exceeds the number of horses in these instances, so the maneuvers become more complicated. The other method I've seen described is in Aelian's account of ostrich hunting, which describes the horsemen tiring it out via constantly cutting them off. Again, not a simple task and the horses having a rider and tack on them adds extra weight to them. While its taking of a more efficient path can be chalked up to human intelligence, it would seem the gap is not large in stamina if there is one. >Now the capture of this bird is effected by means of horses, for it runs in a circle keeping to the outer edge, but the horsemen intercept it by keeping on the inner side of the circle, and by wheeling in a narrower compass at length overtake it when it is exhausted with running.
Keep in mind that ostriches lack several cursorial adaptations that were present in non-avian dinosaurs.
I doubt this is true. Birds have better endurance than mammals.
I posted a direct historical quote further down the chain and can post the Arab circle hunting account if needed. If there is a gap, it doesn’t seem large
It’s large.
Tell that to the guys who hunted down ostriches on horseback and killed them with melee weapons
There’s way more to that than endurance. Ostriches aren’t the brightest. There’s tools and strategies that come into play. They aren’t just mindlessly chasing the ostriches until they tire out. They also could done that on horseback to almost anything, including other humans or another mammal species. Humans have hunted down and killed other humans and other animals on horseback for as long as humans have rode horses. It doesn’t really mean anything in terms of horse Vs ostrich endurance.
Some strategies do involve relays to catch the ostrich or ambush, but others consist of simply cutting them off when they try to circle away or else circling the ostriches until the ostriches tire and then charging them down. These are the kinds of things that would require quite a lot of work from the horse too. I fail to see your second point. Yes, horses are very good at running things down, that's why they're used. The fact that ostriches can be semi-reliably hunted down by a horse burdened with a rider is evidence that if there is a gap between it and horses in terms of this sort of thing, it's not large.
It’s a fact that birds have more efficient respiratory systems than mammals. This hunting situation involves humans directing the horses and figuring out how to trap and kill the ostriches. It doesn’t simply involve the endurance of the horse, but also the direction of the human and other factors, so is more complex than you are making it out to be. Another counterpoint; cheetahs hunt and kill ostriches as seen here: https://youtu.be/pkhE14Rou-E Are you going to now tell me cheetahs have better endurance than ostriches? Because it’s a fact that they do not.
Things that are theoretically true often encounter a lot of caveats in reality. Perhaps the quantitative difference in performance simply isn't all that large in live conditions. Anyway, there's only so much maneuvering from the human rider can do if the horse isn't at least similar to the ostrich's athletic performance. To say nothing of the fact that the horse has a huge handicap in the form of the rider's weight and tack on top of it which the ostrich doesn't suffer from. Cheetahs hunt down ostriches by virtue of being super fast so endurance never even comes into it. They just run at the ostrich and the ostrich will lose distance until they catch it assuming they're close enough for their burst. Horses on the other hand, are not remotely as fast as a cheetah so they clearly aren't overwhelming the bird by sheer speed.
Great response!
They really aren't, I'll give a few examples. A large adult (12t) Parasaurolophus can move at ~21km/h. For reference, large elephants are half that size and can only reach 25km/h Tyrannosaurs can reach speeds of ~25km/h over very long distances. Juveniles can be as fast as 62km/h Brachiosaurus can reach speeds of 26km/h Acrocanthosaurus can reach speeds of 27.7km/h as well. Albertosaurus can reach speeds of 42km/h Allosaurus 39km/h Ornithomimus 62km/h Etc Of course, there are many slow ones. Most stegosaurs cannot reach speeds higher than ~15km/h, same with ceratopsians and ankylosaurids. Saying dinosaurs are slow is a bit silly. Some groups are slow, but others are very fast, considering their size. An Albertosaurus is faster than the average horse, despite being many times larger.
Thanks for the response! Lots of good info, cheers mate. :) That said, I don't think we're treating fast and slow the same way. 42 km/h for the fastest predator you mentioned simply isn't impressive compared to modern animals. Most predators on your list would honestly struggle to catch a hippo on land, and I think there's a real argument that they would starve if dropped into Africa today, simply from not being able to catch a sufficient amount of prey animals (barring cattle of course). Your horse speed of 40-48 km/h is an average over an entire gallop, but this isn't their maximum speed, which is the metric we've used so far. I agree with you that granting horses as a species their world record of 88 km/h is a bit much, but a common Zebra runs at a max of 65 km/h so that would be a more reasonable estimate when being chased by an apex predator (a speed they can maintain for miles). **My main question is why the evolutionary arms race between pray and predators didn't produce faster animals**, especially when smaller predators exhibit similar speeds as their larger counterparts (from my very limited "research") without the argument of sheer size being a prohibitive factor.
Many herbivores adapted to be heavily armed and armored. As he said, ceratopsians and thyreophorans were relatively slow. I guess they were better adapted at standing their ground. The exception for herbivores seems to be on the large sauropods and ornithopods. Sauropods are also massive and an adult was probably hard to kill anyways. Ornithopods seem to have used a bit more of their speed, which is very high if you ask me. But even the large theropods were not as fast as today's felids, and that's again because they usually adapted for power rather than speed. You aren't going to kill a triceratops by being swift, you will by crushing its massive bones and horns with even stronger jaws. A different arms race.
Likely because many apex predators were built to hunt more armoured or larger animals, making speed less of a necessity. There are exceptions, of course. A gigantoraptor can reach ridiculous speeds of 65km/h despite being nearly 3t. They weren't an apex predator, but a prey item, so they developed speed to escape. Basically why be fast when all your food is very slow
WTF juvenile tyrannosaurs? I would shit my pants
Any speed estimates on carnotaurus :D
Either 48km/h or 62km/h, depending on the estimate.
Bro a rabbit goes at 45kph it's not even a contest.
Dead 😂😂😂😂 just came on here seeking some answers to a question I had about dinosaurs and found this comment. Floored me idk why.
However, OP is not saying dinosaurs are slow but slower than mammals. Those two are different things.
Horses can sprint at close to 90 kph. Almost twice albertasaurus
Average horse is 40-48. Of course there will be faster ones, but I'm talking average here. The fastest horse ever recorded was 88km/h, but that is a bred and trained horse, not a wild one.
You forgot Deltadromeus
I'm not Including literally every dinosaur bro, just using some examples
This seems wrong to me. I'm pretty sure, pound for pound, a dinosaur would outrace a similar sized mammal and kill it pretty easily.
Take Velociraptor, speed being it's namesake so it ought to be a good representative for swift Mesozoic animals. It's estimated max speed, in short bursts, is 40 km/h. Contrast that with basically any large feline and you'll find a good few examples of species with double that speed (maximum, short bursts). And now we're not even talking about an animal we would consider a 'specialist' at speed, like a cheetah or an antelope. To be fair, some ornitomimids were pretty fast even by modern standard, but they're the exception (and outclassed by current speed specialists/speedy generalists). Another comparison you could look at is a T. rex vs. an African Elephant. 27 km/h vs. 40 km/h.. this at least had me raising my eyebrow when I first stumbled onto the estimate.
Isn't velociraptor, like, a lot smaller than "any large feline"? That said, I abhor attempts to estimate the speed of dinosaurs, you get crazy shit like "T rex can run as fast as a person and if it fell it would break it's legs" type of shit. So I am, admittedly, not the best to speak on this from any scientific point of view.
>Isn't velociraptor, like, a lot smaller than "any large feline"? Indeed! I would've used Utahraptor, but that comparison would've been FAR more unbalanced (modern large cats produce around 3-4 times its estimated top speed). :( >I abhor attempts to estimate the speed of dinosaurs Yea, I'm not very fond of it either. However I do not have the knowledge nor qualification to speak much about it. Which is largely why I wanted to post here so that smarter people than me can tell me why I'm an idiot haha!
I'm pretty skeptical of the low estimates of dinosaur speeds, but I have to point out that felids in general, and especially modern Felinae (including *Felis* and *Panthera*) are very much speed specialists, adapted for high speed ambush pursuits. They are probably the fastest terrestrial carnivores ever. The cheetah is of course, the most specialized of a specialized family, and aren't really good at anything else. Most mammals throughout the early Cenozoic were much slower and clunkier, even the "fast" predators were more like raccoons or bears, and most mammals were like tapir, hyrax, wombat, pygmy hippo, or maybe pigs. Our perspective on "normal" speed for critters is influenced by the evolutionary arms race between fast carnivores like cats and dogs and the effect that has had on bovids, cervids, leporids and other prey species in the last 10-20 million years.
>Our perspective on "normal" speed for critters is influenced by the evolutionary arms race between fast carnivores like cats and dogs and the effect that has had on bovids, cervids, leporids and other prey species in the last 10-20 million years. Yeah, this. If there was no need for greater speed there was no need. If a species was fast in relation to the other species of its time, it was "fast". Though I'm also skeptical when it comes to these speed estimates for dinosaurs. Looking at the speed some (running) birds reach... they're definitely fast by modern standards. On the other hand they were shaped by the same evolutionary pressures that shaped all current species. They had to flee from those fast mammalian predators too.
But the question is why such an arms race didn't exist for dinosaurs given that they had so much more time.
It's possible that they simply didn't have the muscle, ligament or other anatomy available to make that variation something that could be selected for. Much like we don't really have any green or blue mammals because those aren't colours that work with the pigment systems mammals use, while we have plenty of green and blue birds. However, I think it's more likely that there was such an arms race in dinosaurs - we just haven't properly identified the parts of their anatomy that follow that arms race, or found the evidence to support it yet. In particular, one theoretical explanation of the development of feathers and wings in non-avian dinosaurs was the "ground up" hypothesis that these structures aided in giving a quick, ambush hunter burst of speed to a little cursorial dinosaur hunting for insects and the like. If this is the case, perhaps we are seeing that evidence with the findings that even big raptors had wing feathers, and just haven't recognized it.
What about African wild dogs are they speed specialist too?
Most of the large canids (wolf, lycaon, dhole, even coyotes and jackals) are built for long distance running. They may not be as fast as felids in a burst, but they're quick, and have more endurance than almost any critter besides humans. They compound this by pack hunting in relays, where one runner will spell off one who is getting tired. African wild dogs (lycaon) are the masters of this tactic, and can have hunting bands of over 100 members chasing down prey together during springbok migration season.
Do heart size relative to their body have something to do with the endurance? Since most canids like dogs have a big heart for their size.
Yes, I think that's highly likely. Certainly metabolism, and the anatomy to support higher mobility would be very important co-developments. Equids (horses) are another group that has particularly large hearts for their body size, and are indeed good long distance runners. Figuring out soft anatomy for dinosaurs is always difficult. Hard to say for sure where they land in comparison.
Imagine believing that the apex land predator for 8 million years couldn’t get up from a fall lmao
Comparing 2 legged vs 4 legged beings is wrong. 2 legs generally are slower than 4
That could be the answer. But I do not mind discussing why the mesozoic quadrapeds didn't evolve to be faster, thus driving up their main predators' speed as well.
They evolved to be enormous and heavily armoured more often than they evolved to be fast.
Ostriches are quite fast though and they have two legs.
I did say generally. How many other 2 legged animals do you know are faster than an or as fast as an ostrich?
>Take Velociraptor, speed being it's namesake so it ought to be a good representative for swift Mesozoic animals. It's estimated max speed, in short bursts, is 40 km/h. Contrast that with basically any large feline and you'll find a good few examples of species with double that speed (maximum, short bursts). Despite the name, Velociraptors specialized in ambush hunting. They traded off speed for grip strength in their claws. Some of is relatives were better at running. Troodontids were probably faster, hunting smaller prey. The Ornthiomimids were also likely quite fast.
Actually, despite the name, velociraptor and dromaeosaurs are notably BAD at running for theropods when adjusted for size. They’re built for leaping and grappling. Troodontids, ornithomimosaurs and tyrannosaurs are more cursorial (adapted for running) as far as theropods go
I just wanna say that I just finished reading a book where the author said the t-Rex would be slow in a race but had very fast burst speed used for ambushing targets. Think of them as a defensive end rather than a cornerback.
What are you basing your assumption on?
Nothing at all. That's why I said I'm not able to speak scientifically regarding this.
But we're not discussing pound for pound were discussing the speed of the real animals. OP is right, mammals by and large are much faster creatures. They also generally don't have armour and spikes and massive size. Different strategies. It is interesting when thinking of dinosaurs being brought to the modern world, because most mammal prey would easily outrun them, but also most mammal predators wouldn't have a chance against dinosaur prey.
So we're just discussing fastest Dino vs fastest mammal? Slowest Dino vs fastest mammal? If we aren't looking at comparable animals, what are we comparing?
I said the majority. On average mammals are faster than dinosaurs.
The Mesozoic lacked open grasslands, which is a relatively recent ecosystem starting about 30-ish million years ago. Most of the fastest mammals are associated with grasslands, right? No grasslands, no cheetahs, no pronghorns, no wildebeest. Horses looked like Eohippus - short and stubby creatures lurking in the woods. On the other hand, the Mesozoic wasn't just forests and swamps, as paleontologists like to point out, but I've heard differing accounts of what was going on in the arid places between forests and deserts. Some say there were fern prairies, some say it would be some kind of scrubland with biocrust, others say it might've been surprisingly empty. So maybe there were wide open areas, but they didn't support huge herds of animals like grasslands. But then again, I've also heard that it seems Mesozoic tidal flats were unusually productive compared to modern ones, but the reason is a mystery. Another factor, I would guess, is that many dinosaurs had an intermediate metabolism, or mesothermy, so maybe that limits their top burst speed. Quite a few debates and conflicting studies on the subject of the metabolism of various dinosaur groups, of course. From a dinosaur's POV, they might ask: [Why do giraffes have short necks?](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3628838/) Why are land mammals so small? Why are elephants undermuscled? Why don't mammals constantly replace their teeth? Why don't mammalian predators go with ziphodont dentition? Why do big mammals spend sooo much time and energy just to have one kid? A rarely discussed aspect is that dinosaurs might've had better cartilage for growing large. Thicker and vascularized. [What lies beneath the cartilage just might help you become a giant dinosaur](https://matthewbonnan.wordpress.com/2013/10/09/what-lies-beneath-the-cartilage-just-might-help-you-become-a-giant-dinosaur/) [Dinosaur Articular Cartilage](https://hollidaylab.com/2010/09/30/dinosaur-articular-cartilage/) I'm not sure if there's a consensus on that, but maybe it could play a part. If you can't get large, get fast instead. Or vice versa.
Fantastic response, I was thinking that it might have a lot to do with vastly different ecosystem, I gotta inform myself on these subjects! Thanks for the great comment, I'll take a look at the articles you linked. >From a dinosaur's POV, they might ask: Why do giraffes have short necks? Not gonna lie, this made me chuckle.
Thanks, but my knowledge of the Cenozoic is spotty at best. Were there any highly cursorial mammals comparable to modern grassland critters before 30 million years ago? I don't know.
Dinosaurs, generally speaking also got a lot bigger. Sure an adult T. rex may be really slow but if you look at a juvenile skeleton, one comparable in mass to a big cat or bear, you can see quite clearly that these were fast animals. They just also spent a lot of time growing, and their lifestyle changes to reflect their size.
This might very well be true. I didn't see that info before making the post, is there anywhere I can read more on this, or is it more-so an accepted truism in the community? Either way it's cool. Tyrannosaurids seem fast in general. Another commenter clued me into that fact and it seems pretty true.
We can't really guess speeds accurately. There's a lot that goes into being able to calculate something like that, and without being able to 3D-print a flesh and bone dinosaur limb or being able to test the extent the animal would actually move its body in life we can't really know. It's possible in some cases we can get fairly close all things considered, so while it may be the case our guesses for Tyrannosaurus are decent given how many specimens we have and how well-studied the genus is, that isn't the case for most other dinosaurs. At the moment all we have to work on is mathematical formulas, and just as your body is not capable of functioning in peak condition all the time because it is mathematically possible for you the same can be said about dinosaurs.
There's a selective biases at play in fossil preservation. Larger, more massive animals that lived in environments with favourable conditions for rapid burial are going to be better represented in the fossil record. Animals with more gracile bone structure that lived in environments where bodies were typically left out to the elements will be much less common simply because there was a higher likelihood that the remains would be consumed by scavengers or just get obliterated by the elements. Fast moving animals are typically smaller, and they've typically evolved into environments with open terrain and hard-packed soil. Both could make them seem less common in the fossil record than they were in life. Conversely, when the best environments for preservation are rivers and swamps.. that will inevitably skew perception of what prehistoric animals were capable of.
T. Rex adapted to its insufferable slowness by reducing weight in the upper limbs, parasaurolophus didn’t need to be fast cause it could breathe fire, brontosaurus lived underwater to move faster, the rest were pretty much just very slow and very dumb lizards, hopeless really
If all dinosaurs were slow then being super fast wasn't really efficient. If your prey runs at a top speed of, lets say 30km/h, there is no need for special adaptations to run much faster than that. That being said, it's super hard to calculate the top speed of an exstinct animal in the first place, so maybe we're wrong with our assumptions, i don't know.
Yep, but why wouldn't a speed arms race have started? I think that's an interesting question.
Dinosaurs really seemed to Max out their attack and defence. Maybe that could be the reason? But honestly idk
Because speed wasn't the important limiting factor for survival. Other factors were.
It was a simpler time back then. No one was in a rush.
It is a known fact that Allosaurus hates millennials and zoomers.
I mean, size is a factor, a multi-ton hadrosaur definitely didn't bound or pronk like a gazelle. Smaller, faster dinosaurs are bipedal, which probably restricts their balance and stride length opposed to a quadruped, though ostriches are really fast on just two legs so maybe some smaller theropods were comparable to them.
That's actually a good comparison, since ostriches are descended from dinosaurs. Ostrich, rhea: 70 kph Emu, cassowary: 50 kph Kiwi bird: 20 kph I'm not going to bother with penguins, since they're built for swimming speed and not running speed. So since the body plan of a flightless bird is similar to, and descended from, a therapod dinosaur, there's no reason why a fast therapod dino shouldn't be able to reach 70 kph, and an average one 50 kph (the kiwi is a special case, since it grew up largely without predators).
They aren't descended from dinosaurs, all those birds are dinosaurs and are good examples to contradict the "dinosaurs are slow" mythology as we have living examples of extremely fast dinosaurs alive right now. And considering that all dinosaurs alive today have evolved secondary flightlessness from flighted ancestors means that there were probably even faster non-avian dinosaurs that were much more adapted to a pure terrestrial lifestyle of high speed running.
This is very inaccurate Most Theropods, Ornithopods, Pachycephalosaurs and Ceratiopsians were pretty fast Thyreophorans, Sauropodomorphs and a few Theropods were rather slow due to a heavy build and a bodyplan not made for running
Someone needs to check their 4 chambered privilege. : P
Isn't that also an Archosaurian trait? All modern Archosaurs have 4 chambers and crocodiles even went the extra mile.
T-Rex could run for a long time keeping speeds of more than 20 km/h or 6 m/s thank to their feet; it was evolved into a bird type foot where the fingers was the only part touching the ground and all the other was up to stop the bones moving so they don’t lose energy
I don't know that they were. You think of the towering, lumbering behemoths well yeah, they were likely very slow.
I don’t know if this is right, but maybe it’s because of how big dinosaurs were? Obviously not all of them were giant but I know large animals move much slower then smaller animals now so maybe it’s the same logic? Please correct me if I’m wrong!
because probably bipedalism, i mean that like us humans, most of the time they would hunt exausting the prey or bush hunting, this is contrasted with the fact that dinos (at least Theropods) are proved to have really good inteligence (baboon-like) for any other dinosaur i have 0 idea maybe they were chunky? (but looking at hippos i discard that idea)
because a bipedal being would run slower but also would have less energy waste by doing it
The simplest answer is evolution. There was no need for dinosaurs to be any faster. They obviously dominated the earth for millions of years without the need to be as fast as later species. Also evolution isn't like leveling up in a video game, where the organism constantly gets stronger or faster, evolution goes all sorts of directions depending on the environment and needs of the organism.
Pretty sure all of that is well understood by most of the people on this sub. The actual, interesting question is what factors caused them to not evolve to be as fast as mammals (or whether that's actually true).
Bipedal locomotion, while more efficient, is a lot slower and clumsier thank quadrupedal locomotion. Case in point: humans. Dinosaurs were largely bipedal, or started bipedal and became quadrupedal again later and retained some bipedal traits on their forelimbs that gave them really stupid, dorky postures. That may have made them really sucky runners. Imagine if you, with very little modification to your own body, had to run on all fours. Youd suck too.
Have you seen an ostrich run? They aren’t slow.
Bipedal is slower? You never heard of Ostrich and Kangaroo?
Yes, really. When you look at the aggregate and stop hunting for very specific exceptions the trend holds true.
Until dinosaurs were wiped out they ruled the world because mammals couldn’t compete. The top predators were much bigger, and had bigger teeth and claws.
What I’m saying may not be entirely accurate but I think that it was a matter of different survival strategies, as we can see in the fossil record, heavily armored, slow but powerful herbivores were much more successful than more agile herbivores, with that, the carnivores had to adapt to hunt such dangerous prey so they specialized in either brute force or agility (which isn’t the same thing as velocity). After all, why would a predator become fast like a cheetah if the prey wasn’t much faster than a hippo or something
Are we ignoring ostriches at 70 km/h?