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Mind exercise in Evolution


Moontanman

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Evolution is the survival of the fittest but is our modern ecosystem really the result of survival of the fittest or survival of the luckiest?

Most of the real changes in the biodiversity of the planet resulted from mass extinctions caused by everything from flood lava flows to asteroid impacts are they the real causes of the success of the animals we have now? Even if that is true would modern animals compete well with the best of the lost ages of the Earth?  

If you could take a snapshot of the entire biosphere every million years for the last 500 million years and combine them all at once would modern animals win out or would they face some real challenges and would we possibly end up with a much more diverse ecosystem than we currently have or would modern animals lose out to a great extent?    

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3 minutes ago, Moontanman said:

Evolution is the survival of the fittest but is our modern ecosystem really the result of survival of the fittest or survival of the luckiest?

In all systems stochastic effects play a role in shaping evolution. Especially in small populations, random events can have a huge influence. It should also be noted that being extremely well adapted to a particular niche can make an organism very vulnerable to changes to their environment. So under one condition they may outcompete anything you throw at them, but take away a key component, they may go extinct. The issue with your though experiment is therefore how your combined ecosystem would look like. What is they atmospheric content? What precisely is composition of the plants animals and microbes? All these biotic and abiotic factors and the interaction with each other determine their ultimate success.

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2 hours ago, CharonY said:

In all systems stochastic effects play a role in shaping evolution. Especially in small populations, random events can have a huge influence. It should also be noted that being extremely well adapted to a particular niche can make an organism very vulnerable to changes to their environment. So under one condition they may outcompete anything you throw at them, but take away a key component, they may go extinct. The issue with your though experiment is therefore how your combined ecosystem would look like. What is they atmospheric content? What precisely is composition of the plants animals and microbes? All these biotic and abiotic factors and the interaction with each other determine their ultimate success.

I'd have to assume that those things are all in the right ballpark. most people think of the permian extinction, as an example, just blotted out primitive animals that couldn't compete but recent fossils suggest a quite complex assemblage of sophisticated animals comparable to extant animals. The dinosaurs also present a conundrum, once thought to be big dumb lizards we now know they were really closer to birds and at least a match for modern mammals. The mammals they suppressed were not near as sophisticated as modern mammals and so the competition is debatable on many levels. 

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"Survival of the fittest'" is a term that is inadequate and I think misleading.

I would say evolution is more Response-Ability.  The ability to respond to conditions in ways that make those more favourable to the identified subject.

Genetic diversity giving a greater chance the response that does that can be demonstrated and utilised.

Edited by naitche
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On 10/8/2018 at 8:29 PM, Moontanman said:

just blotted out primitive animals that couldn't compete but recent fossils suggest a quite complex assemblage of sophisticated animals comparable to extant animals.

Well, obviously the ability to compete or adapt is entirely independent on complexity (if that is what is implied with primitive). Rather obviously "primitive" bacteria will be the last survivors long after everything else has died out. Again, it depends on the ecological situation, the available niches, the ability of the organisms to adapt to said niches and in cases of direct competition, the relative ability to utilize the niche. Also note that these are not necessarily stable conditions. For example a species can outcompete another one in a particular niche by extremely effective adaptation. However, that niche may vanish and with it the adaptive advantage. Evolution is best not seen as simply a competitive survival experiment.

 

On 10/9/2018 at 5:54 AM, naitche said:

I would say evolution is more Response-Ability.

Probably something like adaptivity.  

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3 hours ago, CharonY said:

Well, obviously the ability to compete or adapt is entirely independent on complexity (if that is what is implied with primitive). Rather obviously "primitive" bacteria will be the last survivors long after everything else has died out. Again, it depends on the ecological situation, the available niches, the ability of the organisms to adapt to said niches and in cases of direct competition, the relative ability to utilize the niche. Also note that these are not necessarily stable conditions. For example a species can outcompete another one in a particular niche by extremely effective adaptation. However, that niche may vanish and with it the adaptive advantage. Evolution is best not seen as simply a competitive survival experiment.

 

Probably something like adaptivity.  

I understand what you mean but I was thinking of the ecosystem itself, we think and it is commonly taught that our current ecosystem is superior. What i am suggesting that our current ecosystem isn't the only or most complex or advanced. Nearly every animal alive today had its  "twin" and if those animals were thrown together to compete the out come wouldn't be us instead of them due to any inherent superiority. Pitted against each other in a stable ecosystem, just as an example, who would win out, gorgonopsids, velociraptors,  or tigers? 

We humans exist because other successful ecosystems were wiped out by catastrophes not because modern mammals are superior to all that come before..  

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27 minutes ago, Moontanman said:

we think and it is commonly taught that our current ecosystem is superior.

Could you elaborate on that? I honestly have never heard that claim, nor does it make any sense in my mind. I may be wrong, but it sounds almost like as one would view evolution on a developmental axis, which is clearly wrong. 

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We humans exist because other successful ecosystems were wiped out by catastrophes not because modern mammals are superior to all that come before..  

Of course they are not. But extinction happened not necessarily due to catastrophes or direct competition. Event can split populations and drift or different selective pressures can have one population survive and another getting extinct. If your overall claim is that evolution is not a directional or strictly competitive mechanism, you are clearly correct, without the need for the thought experiment.

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16 minutes ago, CharonY said:

Could you elaborate on that? I honestly have never heard that claim, nor does it make any sense in my mind. I may be wrong, but it sounds almost like as one would view evolution on a developmental axis, which is clearly wrong. 

If not directly the superiority of our current biosphere is inferred, read any book about past life and you'll see almost cartoonish illustrations of past life. Admittedly our knowledge is limited but think about the permian extinction. If you look it up you see the ecosphere that was eliminated is illustrated as sparse and full of "primitive" animals when in fact they were just as sophisticated as current animals. Recent years has seen a trend to make the reign of the dinosaurs portrayed as somewhat advanced but the idea of dinosaurs as primitive brutes lumbering around waiting to be killed off lingers on. 

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Of course they are not. But extinction happened not necessarily due to catastrophes or direct competition. Event can split populations and drift or different selective pressures can have one population survive and another getting extinct. If your overall claim is that evolution is not a directional or strictly competitive mechanism, you are clearly correct, without the need for the thought experiment.

But the thought experiment only deals with a sudden mixing not catastrophes. The animals of various eras never actually competed with each other. 

What if they did... 

Edited by Moontanman
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4 minutes ago, Moontanman said:

If you look it up you see the ecosphere that was eliminated is illustrated as sparse and full of "primitive" animals when in fact they were just as sophisticated as current animals. Recent years has seen a trend to make the reign of the dinosaurs portrayed as somewhat advanced but the idea of dinosaurs as primitive brutes lumbering around waiting to be killed off lingers on. 

Well, all I can see is that the literature I have seen portraits a very, very different view. There is of course the challenge to assess biodiversity based on fossil records. However, at least in the scientific community, typically we rarely use the term primitive, unless we talk about e.g. specific physiological structures, but even then it is more the distinction between simple and complex (and often the simple structure works very well in many systems). Considering the time frames some dinosaur fossils were found plus the fact that their descendants with very similar body features survived are ample evidence that they were extremely well adapted. 

So, as a whole I do have a hard time following your premise, but I guess it may be because you may gotten your impression from things that I have not read (and as it seems, agree with).

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10 minutes ago, CharonY said:

Well, all I can see is that the literature I have seen portraits a very, very different view. There is of course the challenge to assess biodiversity based on fossil records. However, at least in the scientific community, typically we rarely use the term primitive, unless we talk about e.g. specific physiological structures, but even then it is more the distinction between simple and complex (and often the simple structure works very well in many systems). Considering the time frames some dinosaur fossils were found plus the fact that their descendants with very similar body features survived are ample evidence that they were extremely well adapted. 

So, as a whole I do have a hard time following your premise, but I guess it may be because you may gotten your impression from things that I have not read (and as it seems, agree with).

There is a good chance i don't have access to the same literature you do but the idea remains what of the Tiger, Velociraptor, or Gorgonopsid? Any animals will do but is one more sophisticated than the others and so would have a distinct advantage? 

I do know as a kid in school it was true that the current inhabitants of our planet were portrayed as superior and that has faded some for dinosaurs and their ilk  but previous ecosystems still get dissed pretty bad... 

Edited by Moontanman
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1 minute ago, Moontanman said:

There is a good chance i don't have access to the same literature you do but the idea remains what of the Tiger, Velociraptor, or Gorgonopsid? Any animals will do but is one more sophisticated than the others and so would have a distinct advantage? 

It would entirely be dependent on the overall ecological niche. One big issue here is that since we do not have any living velociraptors or gorgonopsia, it is very difficult to ascertain what their precise physiology is.  For example, they may be vastly different successful depending on what prey they face. Or some of them are better in conserving energy, which would be a selective advantage if food is more limited. Dealing with changing temperatures may vary, and success could be dependent on which climate you throw them in. They may be susceptible or or resilient to particular diseases and so on. 

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On 10/10/2018 at 6:51 PM, CharonY said:

Could you elaborate on that? I honestly have never heard that claim, nor does it make any sense in my mind. I may be wrong, but it sounds almost like as one would view evolution on a developmental axis, which is clearly wrong. 

Hi CY. I understand your points, and would agree, but prior to some level of your education did you not consider Evolution to be based on what the word "evolution" means when not referring to Evolution specifically? There is definitely an implication in the name.

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John Michael Godier discusses this very notion in his newest video with Paleontologist Dr. Steve Brusatte and his Book Rise and Fall of the Dinosaurs in this video. It's almost an hour long but well worth the watch if you have the time... 

 

 

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The phrase "survival of the fittest" is really an attempt to capture a very complicated process in a few words. So while it helps, it can never cover everything, or be accurate all of the time. 

"the fittest" means the most fit for a particular environment. Which includes animals, plant and weather etc.

In the case of the dinosaurs, the environment changed right around the world within hours. That means that "the fittest" also changed within hours. (maybe longer in the sea)

So it's survival of the fittest, at that point in time. Prior to the Asteroid impact, a lot of big dinosaurs were the fittest. After it, they weren't. Maybe fifty years later, if they had still been around they would have been the fittest again. But it was too late. They were all dead. 

You could argue that if they had somehow survived in tiny pockets, mammals would never have proliferated. It might well be true.

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5 hours ago, J.C.MacSwell said:

Hi CY. I understand your points, and would agree, but prior to some level of your education did you not consider Evolution to be based on what the word "evolution" means when not referring to Evolution specifically? There is definitely an implication in the name.

As in evolution not used for biological evolution? Perhaps. But since the context is biological I do not see it how that would apply.

49 minutes ago, mistermack said:

The phrase "survival of the fittest" is really an attempt to capture a very complicated process in a few words.

It also really only captures the aspect  of natural selection (and even that in a haphazard way and is therefore only rarely used) and does not account for other evolutionary mechanisms.

 

49 minutes ago, mistermack said:

[...] Asteroid impact

That is actually an example where genetic drift is a driving force rather than selection. However, after in the aftermath the changed environmental reality would e.g. cause adaptive radiation.

 

 

 

Edited by CharonY
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2 hours ago, CharonY said:

As in evolution not used for biological evolution? Perhaps. But since the context is biological I do not see it how that would apply.

 

 

 

It applied when they chose the name...Evolution. Prior to that did the word have a specific biological context that was inherently (no pun intended) different? I don't believe it did. I think the term was chosen as it suited the explanation of the development from simpler to more complex and higher order species.

 

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30 minutes ago, J.C.MacSwell said:

It applied when they chose the name...Evolution. Prior to that did the word have a specific biological context that was inherently (no pun intended) different? I don't believe it did. I think the term was chosen as it suited the explanation of the development from simpler to more complex and higher order species.

 

I am still not clear what you are proposing, the modern meaning of the world in biological context is very clear. The meaning outside of biology has roots coming from terms related to ontogeny and even other uses before that (looking at the Latin word evolvere).  Early one they of course had no relationship to species as the concept of changing species was fuzzy at best and was more likely used in other sciences. It is probably true that around the time Darwin proposed his theories, there were discussion about the model you propose: a progress of sorts (often with Lamarckian ideas mixed in). But since that has been cleared up (mostly) I fail to see how going back to 18th-19th century meanings is helpful today.

If you mean whether it is understandable that folks would derive the meaning from other contexts and/or just misunderstand what the biological meaning of evolution is, sure. But again you could say the same for many technical terms.

Edited by CharonY
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2 hours ago, CharonY said:

I am still not clear what you are proposing, the modern meaning of the world in biological context is very clear. The meaning outside of biology has roots coming from terms related to ontogeny and even other uses before that (looking at the Latin word evolvere).  Early one they of course had no relationship to species as the concept of changing species was fuzzy at best and was more likely used in other sciences. It is probably true that around the time Darwin proposed his theories, there were discussion about the model you propose: a progress of sorts (often with Lamarckian ideas mixed in). But since that has been cleared up (mostly) I fail to see how going back to 18th-19th century meanings is helpful today.

If you mean whether it is understandable that folks would derive the meaning from other contexts and/or just misunderstand what the biological meaning of evolution is, sure. But again you could say the same for many technical terms.

That part. I know you have a lot better understanding of this than I do, I'm just surprised you seemed unaware of a pretty common layman's interpretation...

...like this meme...throw an amoeba a couple billion years to the left

Image result for evolution

image.png

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  • 11 months later...

Think of it this way, totally speculation, take the continent of Africa, divide it in half, one half is the peak of modern ecosystem (before people fucked it up) the other half is the cretaceous at it's peak. Would the cretaceous animals wipe out the modern mammals? would the modern mammals wipe out the cretaceous animals or would they merge and form a unique combined ecosystem?     

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