# Can a Species Win/Lose the Evolutionary Arms Race? **URL:** \ **Category:** Factual Questions\ **Created:** [September 2, 2014, 5:32pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270 "2014-09-02T17:32:59Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [September 2, 2014, 5:32pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/1 "2014-09-02T17:32:59Z")
Generally when you hear about species going extinct you hear about changes in environment, or new species being introduced etc. Question I have is if it’s possible for incremental changes in the predator or prey species to render the other obsolete, and unable to cope with predators or catch prey, as the case may be. Meaning suppose for example the predator or prey increases its speed or strength or the like and the corresponding prey or predator is not quick enough in adapting itself. This seems theoretically possible. Are there any instances where an extinction is attributed to this? ---
**Author:** ![chacoguy](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@chacoguy](https://boards.straightdope.com/u/chacoguy)\ **Post date:** [September 2, 2014, 5:58pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/2 "2014-09-02T17:58:01Z")
Well, if you allow humans into the equation, there are dozens of examples. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [September 2, 2014, 6:35pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/3 "2014-09-02T18:35:18Z")
What you have stumbled into is called the Competitive exclusion principle. Here’s the wikipedia page for it. > **[Competitive exclusion principle](https://en.wikipedia.org/wiki/Competitive_exclusion_principle)** > > In ecology, the competitive exclusion principle, sometimes referred to as Gause's law, is a proposition that two species which compete for the same limited resource cannot coexist at constant population values. When one species has even the slightest advantage over another, the one with the advantage will dominate in the long term. This leads either to the extinction of the weaker competitor or to an evolutionary or behavioral shift toward a different ecological niche. The principle has bee The c... Basically, what this says is that if everything else is constant, if two species compete for the same resources, the one with even the slightest advantage will dominate in the long term and will eliminate the other. This situation rarely occurs in the real world, and as the wikipedia page notes, some competing species paradoxically manage to thrive in violation of it. The wikipedia page gives controlled experiments involving yeast and paramecium but does not list any real world examples where it has happened. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 2, 2014, 6:50pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/4 "2014-09-02T18:50:26Z")
There are many examples in the short term of new predators being introduced to an area, and quickly causing the extinction of prey species that are not adapted to them. Such examples are harder to document in evolutionary time, simply because we don’t have the resolution to know the exact timing of a predator reaching an area and the extinction of a prey species. When the Panama land bridge formed about 3 million years ago, it had a host of endemic mammals including many kinds of hoofed animals unrelated to northern forms. Most of these gradually became extinct, probably due to a combination of predation by more efficient northern carnivores and competition with northern herbivores. (A few, however, survived until around 10,000 years ago, when they may have been given the coup de grace by early humans.) ---
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [September 2, 2014, 6:50pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/5 "2014-09-02T18:50:28Z")
> [@engineer\_comp\_geek](#): > > What you have stumbled into is called the Competitive exclusion principle. This seems to be about two species competing for the same resources. I’m thinking more of two species competing against each other, in a predator/prey relationship. Some examples [here](http://en.wikipedia.org/wiki/Evolutionary_arms_race#Examples). To use one of those examples, suppose garter snakes were to evolve resistance to tetrodotoxin faster than newts could up the amount of it they produce, that could leave newts without their primary defense, and could theoretically lead to them being wiped out by overpredation. ---
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [September 2, 2014, 6:52pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/6 "2014-09-02T18:52:40Z")
> [@Colibri](#): > > There are many examples in the short term of new predators being introduced to an area, and quickly causing the extinction of prey species that are not adapted to them. Such examples are harder to document in evolutionary time, simply because we don’t have the resolution to know the exact timing of a predator reaching an area and the extinction of a prey species. As you say, there are plenty of such examples. But that’s not what I’m asking about. I specifically excluded this in the first sentence of the OP. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [September 2, 2014, 8:23pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/7 "2014-09-02T20:23:01Z")
> [@Fotheringay-Phipps](#): > > Generally when you hear about species going extinct you hear about changes in environment, or new species being introduced etc. > > Question I have is if it’s possible for incremental changes in the predator or prey species to render the other obsolete, and unable to cope with predators or catch prey, as the case may be. > > Meaning suppose for example the predator or prey increases its speed or strength or the like and the corresponding prey or predator is not quick enough in adapting itself. > > This seems theoretically possible. Are there any instances where an extinction is attributed to this? I can’t find the site now but years ago read a hypothisis on the saber toothed cats and how the development and length of there sabers was so critical in the ballance between them and thier prey. ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [September 2, 2014, 10:55pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/8 "2014-09-02T22:55:00Z")
If you include human evolution of tool making and language then it has happened with us. We drove several prey species to extinction due to our abilities which we evolved that our prey animals didn’t adapt to. However I don’t know to what degree we were natural predator-prey relations that existed for thousands or millions of years before that. As far as non-tool making evolution, I’m not sure. I wonder if any viruses or bacteria have made any plant or animal species go completely extinct. When you factor in how much faster evolution happens in microbes vs larger animals, I would assume so. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 2, 2014, 11:38pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/9 "2014-09-02T23:38:45Z")
> [@Fotheringay-Phipps](#): > > As you say, there are plenty of such examples. But that’s not what I’m asking about. I specifically excluded this in the first sentence of the OP. The answers are: > [@Fotheringay-Phipps](#): > > Question I have is if it’s possible for incremental changes in the predator or prey species to render the other obsolete, and unable to cope with predators or catch prey, as the case may be. > > Meaning suppose for example the predator or prey increases its speed or strength or the like and the corresponding prey or predator is not quick enough in adapting itself. > > This seems theoretically possible. Yes, this is not only theoretically possible, it’s generally assumed to be true in evolutionary theory. > [@](#): > > Are there any instances where an extinction is attributed to this? There are cases in the fossil record, as I have mentioned, that are speculated to be due to this. However, since this happens in evolutionary time, that is over tens of thousands to millions of years, this is going to be almost impossible to observe directly or to document in the fossil record. ---
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [September 3, 2014, 1:34pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/10 "2014-09-03T13:34:52Z")
> [@Colibri](#): > > There are cases in the fossil record, as I have mentioned, that are speculated to be due to this. I’m still not sure we’re talking about the same thing. You say “_as I have mentioned_”, but what you’ve mentioned is “_examples in the short term of new predators being introduced to an area, and quickly causing the extinction of prey species that are not adapted to them_”, which is **not** what I’m talking about (as mentioned). Perhaps you can list some of your examples. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [September 3, 2014, 2:40pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/11 "2014-09-03T14:40:27Z")
You’re looking for examples where a predator and prey relationship has evolved over a long period of time, so that they’re in balance. Like lions and antelope, for instance. And then the predator species undergoes some bit of natural evolution that makes them overwhelmingly capable to the point that they drive the prey species to extinction. As opposed to new predators moving in, or separately evolving species suddenly coming into contact. Right? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 3, 2014, 3:19pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/12 "2014-09-03T15:19:47Z")
> [@Fotheringay-Phipps](#): > > Perhaps you can list some of your examples. Second paragraph of post #4. While this involved various species entering the range of others, the extinctions it happened over millions of years, rather than immediately. If you’re looking for examples of two species evolving entirely within the same range, and one causing the extinction of the other, I am unaware of any documented cases. As I said, these things happen over such extensive periods of time that they’re going to be almost impossible to document definitively. ---
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [September 3, 2014, 3:27pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/13 "2014-09-03T15:27:31Z")
> [@Smeghead](#): > > You’re looking for examples where a predator and prey relationship has evolved over a long period of time, so that they’re in balance. Like lions and antelope, for instance. And then the predator species undergoes some bit of natural evolution that makes them overwhelmingly capable to the point that they drive the prey species to extinction. > > As opposed to new predators moving in, or separately evolving species suddenly coming into contact. > > Right? Right. Or the converse, in which a prey species evolves to the point where the predators can’t efficiently prey on them and are thus driven to extinction. [As opposed to what Colibri keeps posting, which is not the question.] ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [September 3, 2014, 4:03pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/14 "2014-09-03T16:03:11Z")
I think Colibri is right that such cases, if they exist, will be very difficult to document convincingly. I’d also suggest that such a thing is rather unlikely to happen. The gradual evolutionary processes by themselves are unlikely to make such a dramatic change so quickly that the other species is unable to adapt. Perhaps if the population was very small, or there were another factor involved like an environmental disaster as sort of a one-two punch, or that sort of thing. I can’t think of any examples off the top of my head, either. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 3, 2014, 4:19pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/15 "2014-09-03T16:19:33Z")
One of the problems is that it is rare to see incremental change in the fossil record in a single species. Typically a species remains virtually unchanged over the range of its occurrence in the fossil record, only to be replaced seemingly instantaneously by a similar apparently descendant species. This pattern has been given the name “punctuated equilibrium,” long periods of apparent stasis followed by sudden replacement. The pattern is thought to be due to the fact that most evolutionary change takes place in small, isolated populations and happens comparatively rapidly, so that it is unlikely to leave evidence in the fossil record. So the new species will almost always appear to have come into an area from outside, rather than having evolved in place. This pattern means that it’s extremely unlikely to see two species evolving in tandem, or to establish cause and effect that a change in one species caused the extinction of another. ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [September 3, 2014, 4:28pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/16 "2014-09-03T16:28:13Z")
> [@Smeghead](#): > > I think Colibri is right that such cases, if they exist, will be very difficult to document convincingly. I’d also suggest that such a thing is rather unlikely to happen. The gradual evolutionary processes by themselves are unlikely to make such a dramatic change so quickly that the other species is unable to adapt. Perhaps if the population was very small, or there were another factor involved like an environmental disaster as sort of a one-two punch, or that sort of thing. I can’t think of any examples off the top of my head, either. I think it’s very unlikely to happen with a change in a continuous, physical characteristic, such as strength or speed. It’s just too difficult to make a sudden change in those kind of characteristics without significantly hurting the animal in some other way. But, I think it’s quite possible for something like a new toxin to appear and quickly spread through a population, to such an extent that it dramatically affects the predator-prey relationship (the snake-newt example was IMHO, a good one. Though probably more likely to go the other way, with the prey evolving a new chemical defense). As Colibri notes, though, it’s going to be nigh-impossible to document that kind of thing in the fossil record. ---
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [September 3, 2014, 4:32pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/17 "2014-09-03T16:32:16Z")
OK, I’ll grant it would be very hard to document. But it should be out there as a theory. I’ve never seen this even raised as a possiblity. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 3, 2014, 5:06pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/18 "2014-09-03T17:06:16Z")
> [@Fotheringay-Phipps](#): > > OK, I’ll grant it would be very hard to document. But it should be out there as a theory. I’ve never seen this even raised as a possiblity. See my post #9. It is well established evolutionary theory. You in fact refer to it in the title of the OP. It’s implicit in the evolutionary arms race concept that if one species fails to keep up it will become extinct. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [September 3, 2014, 5:23pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/19 "2014-09-03T17:23:11Z")
The lancehead viper off the coast of Brazil may be a good case study. I believe he has developed a very quick acting poison to stop birds very quickly. I would imagine before this happened he was brought to the verge of extinction. They are so numerous now i would imagine any resident populations of birds that feed in the brush will eventually be threatened. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 3, 2014, 5:30pm UTC](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270/20 "2014-09-03T17:30:19Z")
It might also be mentioned that fossil faunas almost always include several predator species and several prey species. In modern faunas, for example, lions prey on zebras, wildebeest, and many other species, while zebras are preyed on not only by lions but by hyenas and wild dogs. Linking an extinction to a change in a single other species is going to be difficult unless it is an extremely specialized relationship. [Next page](https://boards.straightdope.com/t/can-a-species-win-lose-the-evolutionary-arms-race/697270.md?page=2)