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Author Topic:   Ante-Diluvian Ecology
Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 1 of 15 (456531)
02-18-2008 4:45 PM


I would like to start up a theoretical discussion about ecology in the Ante-Diluvian world of the young-earth creationist (YEC) model of natural history (such as is presented by Ken Ham here).
This model generally requires that all animals and plants (both living and fossil) co-existed until the Flood killed all but the few kinds that God had Noah preserve on the Ark. This means that today's lions and tigers and wolves (or something of their biblical "kinds") had to compete for food, not only with each other, but with yesterday's theropods, gorgonopsids and pelycosaurs, and that today's birds and bats had to share the skies with yesterday's pterosaurs and griffinflies.
In this thread, we will assume that natural selection can occur, as Ken Ham believes, and that most other currently-accepted ecological principles (e.g. Hardy-Weinberg equilibrium, nutrient cycling/energy flow, competitive exclusion, etc.) are also correct. Note that these principles are not generally a matter of disagreement between IDists and evolutionists.
To narrow the topic a bit, let's consider a single organism that I'm sure everybody is familiar with: Tyrannosaurus rex. My question is: How would Tyrannosaurus have effected the Ante-Diluvian ecosystem, assuming that today's animal "kinds" existed alongside it before the Noachian Flood?
Here are a couple interrelated questions to begin this discussion. Please use these as the basis for your argument (though you're free to switch "bison" or "wolf" for something like "moose" or "Smilodon").
1. Could Tyrannosaurus prey on bison? How would the bison avoid predation from Tyrannosaurus?
2. Did Tyrannosaurus compete with the wolf for food (such as bison)? Why or why not?
If this goes well, maybe we could propose a theoretical CGI documentary for Ken Ham and the Creation Museum to produce!
Edited by Bluejay, : Grammar

Signed,
Nobody Important (just Bluejay)

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Admin
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Message 2 of 15 (456538)
02-18-2008 5:47 PM
Reply to: Message 1 by Blue Jay
02-18-2008 4:45 PM


Looks fine other than a typo. Should "moderly" be "moderately"? Not sure. Please fix, then I'll promote this.

--Percy
EvC Forum Director

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Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 3 of 15 (456543)
02-18-2008 6:17 PM
Reply to: Message 2 by Admin
02-18-2008 5:47 PM


Actually, it was supposed to be "modernly," but that sounds stupid, so I switched it to "currently."

Signed,
Nobody Important (just Bluejay)

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Admin
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Message 4 of 15 (456551)
02-18-2008 7:41 PM


Thread moved here from the Proposed New Topics forum.

  
Blue Jay
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Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 5 of 15 (456773)
02-20-2008 12:57 AM
Reply to: Message 1 by Blue Jay
02-18-2008 4:45 PM


Well, No takers? I guess I'll talk to meself for a bit, then.
If the young-earth model is assumed, bison had to have somehow survived co-existence with Tyrannosaurus, for which I can think of a handful of possible explanations. Whatever explanation is given, a beast the size of a tyrannosaur cannot just be swept under the rug: something that big inevitably would have had a dramatic impact on its ecosystem, in one way or another. Given that the bison (a likely prey animal) has survived the onslaught, we can put forth a few hypotheses as to how:
1. The bison is capable of defending itself against a tyrannosaur
2. The bison is capable of outrunning a tyrannosaur
3. The tyrannosaur did not prey on the bison
The bison would likely provide a decent meal for a tyrannosaur, and may have been quite abundant (if its populations a few hundred years ago were representative of its former abundance). Therefore, I see no reason for the tyrannosaur to not attempt to exploit this possible food resource. Thus, I will ignore hypothesis #3. Hypothesis #1 is very unlikely, given the relative sizes and builds of the two animals, so I will also ignore it.
But, hypothesis #2 is plausible. Assuming that the tyrannosaur would attempt to eat bison, and that the bison could not easily hold its own against the tyrannosaur in a fight, it would likely have had to outrun Tyrannosaurus to avoid predation from it. From this information, a young earth creationist would likely theorize that Tyrannosaurus could not run as fast as a bison. He or she would also likely theorize that tyrannosaurs also had very low endurance, or they could have exploited a chase-to-exhaustion tactic.
A slow Tyrannosaurus would also be predicted by the YECist in terms of predator-predator interactions. The wolf, for instance, is comparable to the bison in running speed, and relatively quick, thus providing a possible mechanism by which it could survive competition from the tyrannosaurs. Tyrannosaurus could likely have made its living bullying wolves off their kills (which don't often include adult bison, though). It could presumably do the same to Smilodon, lion, cheetah, cougar, terror bird, Deinonychus, etc. by virtue of its sheer size. The difficulty in this view would be in determining if Tyrannosaurus was well-enough adapted to find enough carrion.
The interaction between wolf and Deinonychus would be much more difficult to explain, however, if the competitive exclusion principle is to be upheld. They are roughly equal in size, perhaps equal in hunting prowess and running speed. This is speculation, but is reasonable: if either was superior, it would have driven the other to extinction, because they are presumably adapted for a very similar niche (given the actual observations of the wolf and the evidence of Deinonychus), and the competitive exclusion principle dictates that only one animal can fill a single niche at a given time.

Signed,
Nobody Important (just Bluejay)

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Replies to this message:
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Larni
Member (Idle past 163 days)
Posts: 4000
From: Liverpool
Joined: 09-16-2005


Message 6 of 15 (456792)
02-20-2008 6:34 AM
Reply to: Message 5 by Blue Jay
02-20-2008 12:57 AM


Well T Rex did seem to be quite slow and I always thought that it was an opportunisting hunter/scavenger. I do doubt wether it could have hunted bison very well or other crafty mammals as it would have been so obvious in its approach (Bison live on plains).
Tyrannosaurus was not a fast runner | Nature
http://www.biomechanics.bio.uci.edu/..._biomech/trex/trx.htm
I think the biggest problem with dinosaurs co existing with modern creatures is the fact that they lay eggs on the ground. These would be a veritable storehouse of easy to access protien for egg eaters.
You also forget that people would have done there best to erradicate any hostile megafauna.
Megalania is a good example of a big ass monitor lizard that went extinct about 40000 BCE. This would have coexisted with the animals you mentioned. Now it's dead.
The thing is that there is no evidence that all these animals coexisted and if through some magic they did you would need climatic conditions that would favour each time periods organisms.
Drop a mammoth into the wrong time period and it dies. Do the same for other creatures and they die.
One way around the problem is to suggest that the climatic conditions of the ante-diluvian realm were very isolated in some way.
I have often wondered 'who would win' if dinosaurs were somehow pulled from the past and I think I concluded that the dinosaurs would 'win' in the short term but laying eggs on land would be the death of them.

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 Message 5 by Blue Jay, posted 02-20-2008 12:57 AM Blue Jay has replied

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bluegenes
Member (Idle past 2477 days)
Posts: 3119
From: U.K.
Joined: 01-24-2007


Message 7 of 15 (456794)
02-20-2008 6:58 AM
Reply to: Message 6 by Larni
02-20-2008 6:34 AM


Larni writes:
I have often wondered 'who would win' if dinosaurs were somehow pulled from the past and I think I concluded that the dinosaurs would 'win' in the short term but laying eggs on land would be the death of them.
It's a favourite hypothesis of mine that the dinosaurs were under pressure from smart mammals for exactly that reason before the K-T event, and their days were perhaps numbered. Hence the survival of those which could lay their eggs out of reach.
I'm sure that the idea must have been suggested before.
As for speculation on a world with T-Rex and buffaloes, we need some answers from YEC's. T-Rex is, I think, found only in North America, which must have been very crowded in between the creation and the flood!

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CTD
Member (Idle past 5869 days)
Posts: 253
Joined: 03-11-2007


Message 8 of 15 (456898)
02-20-2008 4:07 PM
Reply to: Message 5 by Blue Jay
02-20-2008 12:57 AM


quote:
1. The bison is capable of defending itself against a tyrannosaur
2. The bison is capable of outrunning a tyrannosaur
3. The tyrannosaur did not prey on the bison
I'm not sure if I should comment, but I'll do it anyhow.
It is possible that the famed T-Rex might dine on bison. I find it odd that the more typical predator-prey relationships aren't mentioned. Is the wildebeast extinct due to the lion? Is the mosquito extinct due to the bat?
Bison in my grandfather's youth were quite numerous. When the herds combined during migration season, the resultant mass of the creatures spanned from horizon to horizon. I see no consideration that bison may have been too many to be eaten to extinction.
Neither do I see consideration of the common result of overpredation. Is it not possible for the numbers of prey creatures to be reduced to the point that their predators must find other food or starve? We know the dodo was an exception. If it wasn't, I don't think anyone would have ever much noticed the dodo.
Another possibility would be human intervention. Bison are the same kind of animal presently kept and protected by humans.
Neither would I dismiss your first hypothesis too quickly. Cattle of all kinds are prone to stampeding, and a creature as top-heavy as T-Rex, with so little capacity for gray matter could have a great deal of trouble keeping its balance if overrun. The wise Tyrannosaur might well choose not to take her chances around bison.
quote:
The interaction between wolf and Deinonychus would be much more difficult to explain, however, if the competitive exclusion principle is to be upheld.
That's a new one to me, that "competitive exclusion principle". I suggest it might stand a better chance if you apply it to a critter less versatile than the wolf has proven to be.
It's a nice coincidence that just yesterday I saw an evolutionist show about polar bears and grizzlies. They're the same kind of animal, but the polar bear's diet is entirely different. Polar bears have become totally carnivorous, and they pass right by edible plant life because they're no longer aware they can eat it. There's more, but I think one can readily see my point: life is generally capable of surviving under a variety of conditions, and few creatures are restricted to a narrow diet. Pandas and koalas are the only two that come to mind, but maybe I've got bears on the brain.
I do not envy you the argument you've undertaken. I was going to suggest that scanty knowledge about the dinosaurs will make your task highly speculative and you might want to consider creatures we know about that compete for resources. Then I realized the ones we know about haven't driven each other extinct, so they're unsuitable.
I am keenly curious about the pre-flood world, so I can't say I'm sorry this topic came up. Of course I prefer ante-diluvian discussions to anti-diluvian, but one can't always be picky.

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Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 9 of 15 (457039)
02-21-2008 12:21 PM
Reply to: Message 6 by Larni
02-20-2008 6:34 AM


Larni writes:
Well T Rex did seem to be quite slow and I always thought that it was an opportunisting hunter/scavenger. I do doubt wether it could have hunted bison very well or other crafty mammals as it would have been so obvious in its approach (Bison live on plains).
I tend to agree with you about its speed, but the scavenger issue is a little difficult to explain: if it was warm-blooded (as most scientists are thinking these days), it would need to eat a whole lot of carrion. Therefore, in order for this hypothesis to hold, T-rex most likely would have had to have been cold-blooded.
This article proposes an alternative. And, if the ante-diluvian ecosytem had as many large species co-existing as the YEC model predicts, the ecosystem must have been very fertile, and would have provided large amounts of carrion for a tyrannosaurid scavenger.
Larni writes:
I think the biggest problem with dinosaurs co existing with modern creatures is the fact that they lay eggs on the ground.
I have a hard time swallowing this. Ground-nesting has caused no major evolutionary problem for crocodilians or ratites, who would have been easier to bully away from a nest than a tyrannosaur. There is no reason to believe that tyrannosaurs didn't tend their nests as crocodiles and ostriches do.
Larni writes:
You also forget that people would have done there best to erradicate any hostile megafauna.
I seriously doubt Ante-Diluvian humans could have had much influence on tyrannosaurs. How many spears would you need to hock at that guy to take him down? Of course, if Joshua had been there, they might have been able to shout him down. However, we have yet to find tyrannosaur skeletons yielding spear-wounds (or shout-wounds).
Larni writes:
Megalania is a good example of a big ass monitor lizard that went extinct about 40000 BCE.
You can't say "40000 BCE," because we're assuming the YEC model, which means, in this thread, 40000 BCE predated the Creation (i.e. didn't exist).
Also, crocodiles can get as big as Megalania, and they're not extinct.
The thing is that there is no evidence that all these animals coexisted and if through some magic they did you would need climatic conditions that would favour each time periods organisms.
I agree. That's not the point of this thread, though.

Signed,
Nobody Important (just Bluejay)

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Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 10 of 15 (457043)
02-21-2008 12:30 PM
Reply to: Message 7 by bluegenes
02-20-2008 6:58 AM


It's a favourite hypothesis of mine that the dinosaurs were under pressure from smart mammals for exactly that reason before the K-T event, and their days were perhaps numbered. Hence the survival of those which could lay their eggs out of reach.
Again, crocodilians survived the smart-mammalian-egg-thief onslaught, as did many birds. By current phylogenetic understanding, ratites, ducks and galliforms (chickens, pheasants, etc.) are the earliest-diverging groups of birds, and all three groups nest on the ground.
T-Rex is, I think, found only in North America, which must have been very crowded in between the creation and the flood!
You're right: Tyrannosaurus rex has only been found in Montana, Colorado, and surrounding areas.
When I originally composed this thread, I had a long entry about carrying capacity in mind, but I decided to leave it out. Even assuming only a minimum viable population of each species alive on North America, you'd have a very crowded biosphere (which would have been good for a predator/scavenger like Tyrannosaurus). You might be able to explain this with many species of vegetation that regrew very rapidly after grazing, perhaps in part due to something in the pre-flood environment. This, I think, is a stretch, though.

Signed,
Nobody Important (just Bluejay)

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Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 11 of 15 (457075)
02-21-2008 1:24 PM
Reply to: Message 8 by CTD
02-20-2008 4:07 PM


I do not envy you the argument you've undertaken.
I don't actually consider this an argument (I don't really stand behind anything I say here, because I'm not a creationist). I consider it more of an exercise in logic.
I find it odd that the more typical predator-prey relationships aren't mentioned. Is the wildebeast extinct due to the lion? Is the mosquito extinct due to the bat?
The tyrannosaur-bison example was just a prompt to address the overall issue of Ante-Diluvian ecological problems in a manner that would be less confusing than taking into account from the get-go the millions of species that would have to have been extant before the Flood. That's the general idea of a theory: you simplify everything into a model that can be easily examined, and then expand it by adding more parts to the model.
The difference here is that the lion and wildebeest are well-matched (I would say "co-evolved" if I weren't assuming the YEC model). Assumably, Tyrannosaurus was well-matched with prey items large enough to fill its belly (otherwise, it would be constantly hunting or wanting for food). A bison, though not as large as a hadrosaur, would probably be big enough to provide a good meal for a tyrannosaur, which would likely come with less struggling than a Triceratops.
Most small animals survive against large animals by speed and quickness. Note, however, that the bison is not optimized for speed and quickness, but for strength and ruggedness, which suggests (in my mind, at least) that it was not adapted to deal with tyrannosaurs.
Is it not possible for the numbers of prey creatures to be reduced to the point that their predators must find other food or starve?
If the YEC model is true, there were plenty of other animals out there that Tyrannosaurus could feed on as soon as (and while) it drove the easier prey to extinction. Bison would likelier be easier prey than Triceratops, Ankylosaurus or even Parasaurolophus. This is the idea that "you don't have to outrun(outsmart/outbox/outbluff/etc.) the tyrannosaur, you just have to outrun (outsmart/outbox/outbluff/etc.) the other prey animals." So, perhaps I should rephrase my question to include competition between bison and herbivorous dinosaurs?
Cattle of all kinds are prone to stampeding, and a creature as top-heavy as T-Rex, with so little capacity for gray matter could have a great deal of trouble keeping its balance if overrun. The wise Tyrannosaur might well choose not to take her chances around bison.
This is probably a legitimate argument. However, stampeding is a form of running away, not standing to fight. Stampeding can also be used by predators like wolves and lions as a method of identifying weak animals, so it may, in fact, increase the effectiveness of predation.
That's a new one to me, that "competitive exclusion principle". I suggest it might stand a better chance if you apply it to a critter less versatile than the wolf has proven to be.
Competitive exclusion principle (or Gause's law): (paraphrased) Two species in competition for the same set of resources cannot co-exist in a stable, sustainable fashion.
I don't know that I would call the wolf "versatile." Like any apex predator, the wolf is more sensitive to environmental fluctuations than any other animal in the greater North American ecosystems. Granted, it's much more versatile than the tiger or the lion.
However, is there any evidence to suggest that Deinonychus was any less versatile? It is similar in size to the wolf, similar in feeding ecology (presumably), and seems to have taken on prey larger than bison. I would tend to favor Deinonychus over the wolf in a head-to-head match.

Signed,
Nobody Important (just Bluejay)

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Replies to this message:
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Minnemooseus
Member
Posts: 3941
From: Duluth, Minnesota, U.S. (West end of Lake Superior)
Joined: 11-11-2001
Member Rating: 10.0


Message 12 of 15 (457243)
02-21-2008 9:06 PM
Reply to: Message 11 by Blue Jay
02-21-2008 1:24 PM


It's a climate thing?
Note, however, that the bison is not optimized for speed and quickness, but for strength and ruggedness, which suggests (in my mind, at least) that it was not adapted to deal with tyrannosaurs.
Ruggedness - as in "Can live in temperatures much below freezing".
Might it not very well be the case that bison and T-rex were often climatically isolated? They trod the same ground but not at the same time of the year?
I just don't see T-rex hanging out in a Montana winter. Or were the winters much milder =/- 5000 years ago?
Moose

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Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 13 of 15 (457246)
02-21-2008 9:15 PM
Reply to: Message 12 by Minnemooseus
02-21-2008 9:06 PM


Re: It's a climate thing?
Minnemooseus writes:
Might it not very well be the case that bison and T-rex were often climatically isolated? They trod the same ground but not at the same time of the year?
Another consideration worth noting. Maybe mammals, with their warm fur, could escape the predators by staying in the cold. Evolutionary theory seems to suggest that Mesozoic (dinosaur-aged) mammals may have developed their temperature-regulating abilities (otherwise known as warm-bloodedness) to exploit a niche that cold-blooded reptiles couldn't handle: the nighttime.
However, the common view in evolutionary theory today is that dinosaurs were also warm-blooded. In fact, animals believed to be the evolutionary ancestors of tyrannosaurs have been found with evidence of feathers, which indicates that tyrannosaurs may also have had feathers. However, there is no direct evidence of feathers on an actual Tyrannosaurus rex specimen as of yet, so this is still a preliminary hypothesis.
I just don't see T-rex hanging out in a Montana winter. Or were the winters much milder =/- 5000 years ago?
Maybe the "firmament of the heavens" favored milder climates. However, if the climate were milder, that would be one less escape mechanism for the bison.

Signed,
Nobody Important (just Bluejay)

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CTD
Member (Idle past 5869 days)
Posts: 253
Joined: 03-11-2007


Message 14 of 15 (457273)
02-22-2008 5:07 AM
Reply to: Message 11 by Blue Jay
02-21-2008 1:24 PM


quote:
This is probably a legitimate argument. However, stampeding is a form of running away, not standing to fight. Stampeding can also be used by predators like wolves and lions as a method of identifying weak animals, so it may, in fact, increase the effectiveness of predation.
Tell it to the jokers who travel to Spain to run "with" the bulls.
When I was young, I read about how bison deal with rattlesnakes. The largest members of the herd gather together and the rest of the herd clears out. Then the big ones run the reptile down together. That's the case if the snake is discovered when the herd's just grazing. A moving herd takes little notice and doesn't leave many scraps behind for the birds.
You're thinking in binary "fight or flight" terms. For purposes of a private exercise in logic this may serve, but I remain unconvinced. Even if a stampede starts as a "flight" response, it can end up going any direction if not guided. I'm no cowboy, so I don't know how much skill may or may not be involved.
As for ante-diluvian wolves lacking versatility, I don't follow. These are the ancestors of foxes, coyotes, and every other type of dog. They're not very restricted when it comes to diet or habitat.
Your reasoning seems to rule out the survival of many prey animals. How can wild sheep survive when they have wolves & big cats in the neighborhood?
Shoot, sheep are so problematic conceptually I checked to see if there still are wild sheep. Looks like there are. http://www.sciencedaily.com/...ases/2007/06/070620154911.htm
http://www.bighorninstitute.org/wildsheep.htm

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Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 15 of 15 (457532)
02-23-2008 10:30 PM
Reply to: Message 14 by CTD
02-22-2008 5:07 AM


As for ante-diluvian wolves lacking versatility, I don't follow. These are the ancestors of foxes, coyotes, and every other type of dog. They're not very restricted when it comes to diet or habitat.
So, would your contention then be that the wolf could have adapted to a less carnivorous diet in the Ante-Diluvian ecosystems? This would have avoided from competition from the deinonychosaurs, no doubt.
You're thinking in binary "fight or flight" terms. For purposes of a private exercise in logic this may serve, but I remain unconvinced. Even if a stampede starts as a "flight" response, it can end up going any direction if not guided. I'm no cowboy, so I don't know how much skill may or may not be involved.
The point wasn't how much you could get hurt. The point was that the bison ran away. That is their strategy for dealing with wolves. Furthermore, the wolves use this to find out which bison would be easiest to kill. Therefore, even if the bison had adapted for agressive stampeding, the wolves adapted to exploit it. Its said that bison stand a better chance if they stand their ground.
Your reasoning seems to rule out the survival of many prey animals. How can wild sheep survive when they have wolves & big cats in the neighborhood?
Shoot, sheep are so problematic conceptually I checked to see if there still are wild sheep. Looks like there are.
You're still missing the point. This isn't a simple predator-prey relationship. When dogs arrived on Mauritius, the dodo disappeared. When dogs arrived on Australia, many species of native marsupial went extinct. There isn't always a complete balance. Things do go extinct when predators become too good.
Wolves and big cats are not Tyrannosaurus. Wolves can't bite bison in half with one flex of the temporalis muscle. If bison co-existed with Tyrannosaurus, it must have a way to survive it, yeah? Maybe it was a weakness of the tyrannosaur, or maybe it was a strength of the bison.
About sheep. You say you looked it up. I've been up in the mountains with those sheep (within twenty feet, in fact). They move across the mountains like no wolf or cougar (or even deer) ever could. That's how they escape the wolf and the cougar. That's why they're not extinct.
From the posts I've read here, I assume everyone's comfortable with the idea that bison can outrun tyrannosaurs, yeah? Therefore, tyrannosaurs were scavengers, wolves were herbivores, etc.

Signed,
Nobody Important (just Bluejay)

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