It’s interesting but it doesn’t really explain anything, at best it reasons backward from how things ended up. Why weren’t the bone-crushing dogs able to compete with the big cats in North America, what wasn’t it the other way around and the bone-crushing dogs didn’t invade Asia and outcompete the big cats? You can’t really explain contingent events, you can just describe them. If two species compete, one of them perhaps wins, but you can’t say why that species had the qualities needed to win and the other didn’t.
There are big animals still around today more closely related to dogs than to cats. They’re called “bears”, which interestingly seems to be a euphemism.
I saw a video some years ago about humans as runners and the evolutionary advantages we have as hunters. That video claimed that humans, either solo or with in small numbers, were good at running prey to exhaustion in especially in hot climates, for two reasons.
1) We don’t have fur and can sweat. So, we generally don’t run into heat exhaustion like most furry animals do. 2) Our Achilles tendons are amazing springs and facilitate running at modest speeds with great efficiency and long distances.
@Tommy Jay: That video claimed that humans, either solo or with in small numbers, were good at running prey to exhaustion
Easy to confirm. Ever take a dog on a long run?
If I remember right from my anthro classes about 1/3 hunts came back with something worth eating, and “running” down prey is a lot more like walking, with short periods of running, and it takes several days for a large animal.
The big herbivores have to eat all the time. If they aren’t allowed to eat for a few days they fall over, more or less.
Why weren’t the bone-crushing dogs able to compete with the big cats in North America, what wasn’t it the other way around and the bone-crushing dogs didn’t invade Asia and outcompete the big cats? You can’t really explain contingent events, you can just describe them. If two species compete, one of them perhaps wins, but you can’t say why that species had the qualities needed to win and the other didn’t.
I don’t know, after watching the whole video I think it was more or less able to explain the theory of how bone-crushing dogs were likely outcompeted by new big cats coming from Eurasia. Here’s an excerpt from the auto-generated text transcription of the video.
(Sorry about the lack of punctuation or paragraphs. Evidently Youtube’s speech-to-text generation isn’t really sophisticated enough to handle things like that…)
it safe and that may have saved them
because everything changed when the cats
arrived for millions of years the
Americas belonged to the dogs the big
cats hadn’t even shown up yet it was a
canine continent ruled by bone crushers
and pack hunters with no felines in
sight then the migration happened
members of the cat family originally
from Eurasia made their way into North
America at first they were just another
competitor but it didn’t take long for
them to start climbing the food chain
unlike the big dogs these new predators
didn’t rely on stamina or teamwork they
brought a completely different playbook
stealth power and precision and when
they moved in they didn’t just coexist
they started eating the same prey the
exact same prey that the biggest dogs
relied on for survival that overlap
turned into direct competition and the
dogs lost the big boroagines animals
like epision had gone all in on one
strategy huge size huge skulls slow
movement specialized diets they were
built to take down and break apart giant
animals but cats like the
saber-tooththed smileon were doing the
same job better faster quieter more
agile able to hunt solo more efficient
with energy and equipped with claws and
joints that gave them more control
during the kill they didn’t just bite
they wrestled prey to the ground and
finished it with a fatal strike it was
cleaner faster and cost less in calories
once again one branch of predators
pushed itself too far into
specialization and just like the
Hesperoscion before them the big dogs
were slowly pushed out evolution
You might disagree with some or all of the ideas of that explanation, but it at least doesn’t seem to be terribly unreasonable to me. Essentially the big cats had more effective tools for the niche that they shared with the bone-crushers (that niche being predators that are big solo ambushers who rely on short bursts of overwhelming power to deliver a quick death to their prey as opposed to the smaller pack based distance hunters that are able to gradually wear down their prey and/or overwhelm them with numbers).
As to why bone-crushing dogs didn’t migrate to Eurasia to out compete the big cats there, that seems self evident if you buy the first argument anyway. That being that it’s extremely likely that a population of bone crushers did make their way to Eurasia and couldn’t compete with the already established animals in their niche (that being primarily the big cats).
Bears don’t exactly share the same niche as big cats, though there’s certainly a lot of overlap. Most species of bears are omnivores (with the exception of polar bears, but then you get into ranges) while big cats are hypercarnivores whose diet is almost exclusively meat from prey. It’s fun to imagine what would happen if /when a prehistoric bear like the short faced bear (a monster that would dwarf a modern grizzly) met up with a smilodon.
Easy to confirm. Ever take a dog on a long run? — NC
Only German shepherds on medium runs. Another bad example. And I have walked dogs to exhaustion. They were not hunting dogs, and I don’t think the large animals could last for more than a day in many cases. You are likely correct about walking and jogging on a hunt; and the modest success rate.
Plus, I doubt the average modern sedentary male, even a relatively fit one, could cut it as a hunter of that style.
@Nonapod:Essentially the big cats had more effective tools for the niche that they shared with the bone-crushers
But why? Your long quote answers “how” but not “why”. Why didn’t the bone-crushing dogs have the better adaptations? No one knows the answer to that. Species get what they get. The big cats got ones that worked better against the bone-crushing dogs, and it’s not so hard to explain “how” they were better, but it’s not explained “why” they got those better ones and bone-crushing dogs didn’t.
An analogy might be a YouTube video that says it will explain why I won Powerball when nobody else did, and then says I did that by buying a ticket and having the right number and nobody else did that. Okay, but why me and not somebody else? Well, because.
@Nonapoad: Youtube’s speech-to-text generation isn’t really sophisticated enough to handle things like that…
I use ChatGPT to reformat YouTube output for readability.
You can go to chat.openai.com (or click “Get Free” on openai.com/chatgpt) and click Sign up for free.
I’m sure other AIs will work too.
@Niketas Choniates
I believe the video goes into this a bit, but essentially the bone-crushers tools for taking down prey were their burst speed, strength, and their powerful jaws. So to take down, say, a big herbivore like a bison (or whatever rough analogue animal of that time period) a bone-crushing dog would have to get as close to them as possible undetected, then charge to quickly close the distance. Once the bone-crusher is close enough they could attempt push them down and try to take a big bite out of the prey, ideally in the jugular but that may not always be feasible.
Now at close distances the advantages of a big cat might become more clear. Unlike the bone-crushing dog, a big cat not only has powerful jaws, but they also have sharp claws for gripping onto large prey as well as a bit more freedom of motion in their shoulders and back (which I think the video mentioned in passing) so they can more easily hold onto their prey. If you’ve ever watched videos of lions wrestling a large animal down you’ll know what I’m talking about.
The the claws on the paws of the big bone-crushing dogs aren’t really optimal for gripping prey like those on a big cat, rather they’re more optimised for supporting walking and running. They also lack the ability to sheath their claws like cats can. Consequently they can’t really impose their will as efficiently as a big cat can and their prey is more likely to escape. In the era before the big cats came to North America, the big bone-crushing dogs having their prey escaping sometimes might not have been as big a deal. But once the more efficient killers came onto the scene things started to change.
@Nonapod: Those are great “how” explanations. But why didn’t, for example, bone-crushing dogs get an ability to sheathe their claws, and big cats did? No one knows. They got what they got. Perhaps there could have been some other predator with some even better adaptation than either had, but why wasn’t there? No one knows.
It doesn’t take all that much for a species to last for bezillions of years, some of them just seem to nail their niche and then that niche doesn’t change and they don’t change much, like Latimeria (the coelacanths) or sharks. And some of them, like pandas, it’s like how are they not extinct already, it’s like nothing they have does better than just barely work. They get what they get, and sometimes it’s just good enough and sometimes it’s not.
But why didn’t, for example, bone-crushing dogs get an ability to sheathe their claws, and big cats did? No one knows. They got what they got. Perhaps there could have been some other predator with some even better adaptation than either had, but why wasn’t there? No one knows.
Technically it’s a product of the way evolution works. Evolution is an iterative optimization process involving random change and variables like energy expenditure. As such it doesn’t result in the qualitative absolute “best” result, just the result that is the most optimized for a particular set of circumstances over a given time frame and available energy/resources whatever. If it was always about finding the absolute best result, then I suppose preditors would all have all evolved laser beams to blast their prey, or at least a bone-crushing dogs would have all the adaptions of the big cats in the same time frame. But instead they had adaptions that were “good enough” for the given set of circumstances at the time. They were successful. They could catch enough prey to survive to pass on their genes to the next generation. That is… until circumstances changed with the arrival of the big cats.
Think of the problems we have with introduced invasive species. If evolution worked to find the absolute best result in all cases then such problems would never happen. If every animal had a perfect solution, these invasive species would be no better or worse than the current organisms in the environment that they were introduced to. But instead we a situtation where some new species comes in and has some adaption or advantage that the natives species have no answer for because the invaders evolved in an entirely different ecosystem that had different pressures, requirements, strictures whatever.
My previous Weimaraner always wanted to go on. On to the next corner, on to the rise. Me saying “hey, the walk is just as long going home!”
Evolution is an iterative optimization process involving random change and variables like energy expenditure . How often are mutations beneficial versus harmful to the species?
@Brian E:How often are mutations beneficial versus harmful to the species?
Under 50%. The smaller the effect of the mutation, the closer to 50%, the larger, closer to 0% are beneficial. Even a small beneficial mutation does not take many generations to spread through the gene pool.
The reason they are more harmful the larger effect they have is because the non-mutated version was already doing decently well. If you’re close to optimum already, a large adjustment in any direction probably took you farther from optimum.
A bit like those toys where you shake a marble into a small shallow depression, I suppose: a big shake is sure to screw it up, a small shake might improve things.
The essence of natural selection is non-random death applied to genetic variation which may have come about randomly.
Niketas Choniates on July 9, 2025 at 2:41 pm:
“… Species get what they get….”
Evolution has to “make do” with what it has available. And that is how we have ended up a few 100M years later having our third ear bone evolved from the jaw bone of a fish.
Brian E on July 9, 2025 at 8:38 pm:
Evolution is an iterative [“optimization” removed] process involving random change and variables like energy expenditure . How often are mutations beneficial versus harmful to the species?”
Thank you for that word change to better emphasize that evolution is not a directed or design process, but a simple passive result of changes at the genetic, cell, tissue, and body levels [See Philip Bell: How Life Works (2023)]. Bell points out that changes to DNA are now recognized as not the only biochemical level changes that impact higher level bio elements. Life appears to provide for quite a bit of flexibility in that area.
It is not survival of the fittest, but of the better adapted for a given environment (time and place). And when we get to the level of humanity, we also can evolve cultures that aid or hinder our ability to survive, as individuals or as groups. Bell does not discuss that.
NC, also thanks for answering Brian’s question about mutational benefits.
…[There was] a vetting process that came down to three finalists: Walz, Pennsylvania Gov. Josh Shapiro and Arizona Sen. Mark Kelly.
All three candidates did a final interview with Harris at her residence…. [W]hen asked what they wanted to drink, Shapiro and Kelly chose water while Walz chose Diet Mountain Dew….
Figures.
(And the rest, as they say, is history….)
It’s likely way under 50%, maybe closer to 1%.
It’s fantastical to think we’re having this conversation due to some random process that produced LUCA some 4 billion years ago.
A Creator is a more likely scenario. For all we know what we call “dark energy” is merely the effect God has on our universe.
Certain of the big cats had a “thumb” claw in that one claw was somewhat separated from the others and could grip prey. Didn’t look like what we see today. It would be an advantage over anything the dogs had in that line.
I believe the idea of man-the-runner presumes an injury at the start of the pursuit, either from a close ambush or a thrown weapon like a spear. You’re not going to drop a large herbivore with a spear thrust. But if it starts bleeding or its mobility is impaired at the beginning, things might go a lot faster.
To the extent there is a significant difference between dogs and pack hunting on one hand and cats as solitary hunters, it shows in their how they relate to humans. Dogs can read people people because they had to read other pack members. They had to grasp a tactical situation–he’s already got the throat from that side so I’ll…… Are comfortable in groups once familiar with their companions.
Seen several different families with large dogs of the hunter/retrieval variety out in public with little kids. Some of these big furry puppies who wouldn’t hurt a flea turn to raging pitbulls when a stranger gets close to their little humans. It wears off as the kids get bigger. But, man, some occasions….. Had a golden retriever nearly pull my arm off while out walking with my then two-year old granddaughter and somebody came across the street toward us. Not sure cats would bother.
Probably a result of pack behavior and instinct.
“…Not sure cats would bother.”
Well there’s always this…but it may be the exception that proves the rule.
Still…pretty impressive!
Good kitty, GOOOD kitty…
It’s interesting but it doesn’t really explain anything, at best it reasons backward from how things ended up. Why weren’t the bone-crushing dogs able to compete with the big cats in North America, what wasn’t it the other way around and the bone-crushing dogs didn’t invade Asia and outcompete the big cats? You can’t really explain contingent events, you can just describe them. If two species compete, one of them perhaps wins, but you can’t say why that species had the qualities needed to win and the other didn’t.
There are big animals still around today more closely related to dogs than to cats. They’re called “bears”, which interestingly seems to be a euphemism.
I saw a video some years ago about humans as runners and the evolutionary advantages we have as hunters. That video claimed that humans, either solo or with in small numbers, were good at running prey to exhaustion in especially in hot climates, for two reasons.
1) We don’t have fur and can sweat. So, we generally don’t run into heat exhaustion like most furry animals do. 2) Our Achilles tendons are amazing springs and facilitate running at modest speeds with great efficiency and long distances.
@Tommy Jay: That video claimed that humans, either solo or with in small numbers, were good at running prey to exhaustion
Easy to confirm. Ever take a dog on a long run?
If I remember right from my anthro classes about 1/3 hunts came back with something worth eating, and “running” down prey is a lot more like walking, with short periods of running, and it takes several days for a large animal.
The big herbivores have to eat all the time. If they aren’t allowed to eat for a few days they fall over, more or less.
https://babylonbee.com/news/tsa-announces-passengers-no-longer-have-to-remove-their-shoes-before-being-fondled
Well baby steps
https://x.com/kausmickey/status/1942750118329082287
Some people cant take yes for an answer
I don’t know, after watching the whole video I think it was more or less able to explain the theory of how bone-crushing dogs were likely outcompeted by new big cats coming from Eurasia. Here’s an excerpt from the auto-generated text transcription of the video.
(Sorry about the lack of punctuation or paragraphs. Evidently Youtube’s speech-to-text generation isn’t really sophisticated enough to handle things like that…)
You might disagree with some or all of the ideas of that explanation, but it at least doesn’t seem to be terribly unreasonable to me. Essentially the big cats had more effective tools for the niche that they shared with the bone-crushers (that niche being predators that are big solo ambushers who rely on short bursts of overwhelming power to deliver a quick death to their prey as opposed to the smaller pack based distance hunters that are able to gradually wear down their prey and/or overwhelm them with numbers).
As to why bone-crushing dogs didn’t migrate to Eurasia to out compete the big cats there, that seems self evident if you buy the first argument anyway. That being that it’s extremely likely that a population of bone crushers did make their way to Eurasia and couldn’t compete with the already established animals in their niche (that being primarily the big cats).
Bears don’t exactly share the same niche as big cats, though there’s certainly a lot of overlap. Most species of bears are omnivores (with the exception of polar bears, but then you get into ranges) while big cats are hypercarnivores whose diet is almost exclusively meat from prey. It’s fun to imagine what would happen if /when a prehistoric bear like the short faced bear (a monster that would dwarf a modern grizzly) met up with a smilodon.
Easy to confirm. Ever take a dog on a long run? — NC
Only German shepherds on medium runs. Another bad example. And I have walked dogs to exhaustion. They were not hunting dogs, and I don’t think the large animals could last for more than a day in many cases. You are likely correct about walking and jogging on a hunt; and the modest success rate.
Plus, I doubt the average modern sedentary male, even a relatively fit one, could cut it as a hunter of that style.
@Nonapod:Essentially the big cats had more effective tools for the niche that they shared with the bone-crushers
But why? Your long quote answers “how” but not “why”. Why didn’t the bone-crushing dogs have the better adaptations? No one knows the answer to that. Species get what they get. The big cats got ones that worked better against the bone-crushing dogs, and it’s not so hard to explain “how” they were better, but it’s not explained “why” they got those better ones and bone-crushing dogs didn’t.
An analogy might be a YouTube video that says it will explain why I won Powerball when nobody else did, and then says I did that by buying a ticket and having the right number and nobody else did that. Okay, but why me and not somebody else? Well, because.
@Nonapoad: Youtube’s speech-to-text generation isn’t really sophisticated enough to handle things like that…
I use ChatGPT to reformat YouTube output for readability.
You can go to chat.openai.com (or click “Get Free” on openai.com/chatgpt) and click Sign up for free.
I’m sure other AIs will work too.
@Niketas Choniates
I believe the video goes into this a bit, but essentially the bone-crushers tools for taking down prey were their burst speed, strength, and their powerful jaws. So to take down, say, a big herbivore like a bison (or whatever rough analogue animal of that time period) a bone-crushing dog would have to get as close to them as possible undetected, then charge to quickly close the distance. Once the bone-crusher is close enough they could attempt push them down and try to take a big bite out of the prey, ideally in the jugular but that may not always be feasible.
Now at close distances the advantages of a big cat might become more clear. Unlike the bone-crushing dog, a big cat not only has powerful jaws, but they also have sharp claws for gripping onto large prey as well as a bit more freedom of motion in their shoulders and back (which I think the video mentioned in passing) so they can more easily hold onto their prey. If you’ve ever watched videos of lions wrestling a large animal down you’ll know what I’m talking about.
The the claws on the paws of the big bone-crushing dogs aren’t really optimal for gripping prey like those on a big cat, rather they’re more optimised for supporting walking and running. They also lack the ability to sheath their claws like cats can. Consequently they can’t really impose their will as efficiently as a big cat can and their prey is more likely to escape. In the era before the big cats came to North America, the big bone-crushing dogs having their prey escaping sometimes might not have been as big a deal. But once the more efficient killers came onto the scene things started to change.
@Nonapod: Those are great “how” explanations. But why didn’t, for example, bone-crushing dogs get an ability to sheathe their claws, and big cats did? No one knows. They got what they got. Perhaps there could have been some other predator with some even better adaptation than either had, but why wasn’t there? No one knows.
It doesn’t take all that much for a species to last for bezillions of years, some of them just seem to nail their niche and then that niche doesn’t change and they don’t change much, like Latimeria (the coelacanths) or sharks. And some of them, like pandas, it’s like how are they not extinct already, it’s like nothing they have does better than just barely work. They get what they get, and sometimes it’s just good enough and sometimes it’s not.
Technically it’s a product of the way evolution works. Evolution is an iterative optimization process involving random change and variables like energy expenditure. As such it doesn’t result in the qualitative absolute “best” result, just the result that is the most optimized for a particular set of circumstances over a given time frame and available energy/resources whatever. If it was always about finding the absolute best result, then I suppose preditors would all have all evolved laser beams to blast their prey, or at least a bone-crushing dogs would have all the adaptions of the big cats in the same time frame. But instead they had adaptions that were “good enough” for the given set of circumstances at the time. They were successful. They could catch enough prey to survive to pass on their genes to the next generation. That is… until circumstances changed with the arrival of the big cats.
Think of the problems we have with introduced invasive species. If evolution worked to find the absolute best result in all cases then such problems would never happen. If every animal had a perfect solution, these invasive species would be no better or worse than the current organisms in the environment that they were introduced to. But instead we a situtation where some new species comes in and has some adaption or advantage that the natives species have no answer for because the invaders evolved in an entirely different ecosystem that had different pressures, requirements, strictures whatever.
My previous Weimaraner always wanted to go on. On to the next corner, on to the rise. Me saying “hey, the walk is just as long going home!”
Evolution is an iterative
optimizationprocess involving random change and variables like energy expenditure . How often are mutations beneficial versus harmful to the species?@Brian E:How often are mutations beneficial versus harmful to the species?
Under 50%. The smaller the effect of the mutation, the closer to 50%, the larger, closer to 0% are beneficial. Even a small beneficial mutation does not take many generations to spread through the gene pool.
The reason they are more harmful the larger effect they have is because the non-mutated version was already doing decently well. If you’re close to optimum already, a large adjustment in any direction probably took you farther from optimum.
A bit like those toys where you shake a marble into a small shallow depression, I suppose: a big shake is sure to screw it up, a small shake might improve things.
The essence of natural selection is non-random death applied to genetic variation which may have come about randomly.
Niketas Choniates on July 9, 2025 at 2:41 pm:
“… Species get what they get….”
Evolution has to “make do” with what it has available. And that is how we have ended up a few 100M years later having our third ear bone evolved from the jaw bone of a fish.
Brian E on July 9, 2025 at 8:38 pm:
Evolution is an iterative [“optimization” removed] process involving random change and variables like energy expenditure . How often are mutations beneficial versus harmful to the species?”
Thank you for that word change to better emphasize that evolution is not a directed or design process, but a simple passive result of changes at the genetic, cell, tissue, and body levels [See Philip Bell: How Life Works (2023)]. Bell points out that changes to DNA are now recognized as not the only biochemical level changes that impact higher level bio elements. Life appears to provide for quite a bit of flexibility in that area.
It is not survival of the fittest, but of the better adapted for a given environment (time and place). And when we get to the level of humanity, we also can evolve cultures that aid or hinder our ability to survive, as individuals or as groups. Bell does not discuss that.
NC, also thanks for answering Brian’s question about mutational benefits.
Speaking of evolution…
…here’s a curious one:
“Harris ‘went with her gut’ to select Tim Walz as running mate after ‘overly ambitious’ Josh Shapiro left ‘bad impression’…”
https://nypost.com/2025/07/09/media/harris-went-with-her-gut-on-decision-to-pick-walz-as-her-running-mate-over-shapiro-book/
Key grafs:
Figures.
(And the rest, as they say, is history….)
It’s likely way under 50%, maybe closer to 1%.
It’s fantastical to think we’re having this conversation due to some random process that produced LUCA some 4 billion years ago.
A Creator is a more likely scenario. For all we know what we call “dark energy” is merely the effect God has on our universe.
Certain of the big cats had a “thumb” claw in that one claw was somewhat separated from the others and could grip prey. Didn’t look like what we see today. It would be an advantage over anything the dogs had in that line.
I believe the idea of man-the-runner presumes an injury at the start of the pursuit, either from a close ambush or a thrown weapon like a spear. You’re not going to drop a large herbivore with a spear thrust. But if it starts bleeding or its mobility is impaired at the beginning, things might go a lot faster.
To the extent there is a significant difference between dogs and pack hunting on one hand and cats as solitary hunters, it shows in their how they relate to humans. Dogs can read people people because they had to read other pack members. They had to grasp a tactical situation–he’s already got the throat from that side so I’ll…… Are comfortable in groups once familiar with their companions.
Seen several different families with large dogs of the hunter/retrieval variety out in public with little kids. Some of these big furry puppies who wouldn’t hurt a flea turn to raging pitbulls when a stranger gets close to their little humans. It wears off as the kids get bigger. But, man, some occasions….. Had a golden retriever nearly pull my arm off while out walking with my then two-year old granddaughter and somebody came across the street toward us. Not sure cats would bother.
Probably a result of pack behavior and instinct.
“…Not sure cats would bother.”
Well there’s always this…but it may be the exception that proves the rule.
Still…pretty impressive!
Good kitty, GOOOD kitty…
https://www.youtube.com/watch?v=LSG_wBiTEE8&pp=0gcJCfwAo7VqN5tD