Thread: Evolution Question

Survival of the fittest? That is a catch phrase I have heard a million times. According to the Darwinian theory, traits that are successful in a given environment are passed on genetically to subsequent generations.

However, every environment has a variety of species. Often times there is at least one species that resembles the common ancestor, perhaps an intermediate species, and an end species.

So my question is this: Why did the common ancestor survive along with the end species? If it is an advantage for reptiles to evolve into birds and mamals, why are there any reptiles left? Obviously a bird/reptile was not more suited to the environment than just a plain old reptile, or the bird/reptile would have survived and the reptile would be extinct--and given enough time, all species would resemble the end species: birds and mamals--even humans--and the common ancestors would fall to the way side. Yet, the single cells we evolved from are still around and living in our environment, and they are well suited, perhaps better suited. So how does the Darwinian theory account for this? Or is there a more modern theory that accounts for it?

Originally Posted by williampinn

Survival of the fittest? That is a catch phrase I have heard a million times. According to the Darwinian theory, traits that are successful in a given environment are passed on genetically to subsequent generations.

However, every environment has a variety of species. Often times there is at least one species that resembles the common ancestor, perhaps an intermediate species, and an end species.

So my question is this: Why did the common ancestor survive along with the end species? If it is an advantage for reptiles to evolve into birds and mamals, why are there any reptiles left? Obviously a bird/reptile was not more suited to the environment than just a plain old reptile, or the bird/reptile would have survived and the reptile would be extinct--and given enough time, all species would resemble the end species: birds and mamals--even humans--and the common ancestors would fall to the way side. Yet, the single cells we evolved from are still around and living in our environment, and they are well suited, perhaps better suited. So how does the Darwinian theory account for this? Or is there a more modern theory that accounts for it?

I think this is a good question.

My answer is this:

Think about it this way: Wal-Mart comes into town and outcompetes everybody, driving stores out of business. Will it drive farms out of business? No, because, like the reptiles and reptile-birds, they are not competing for the same resources.

The bird-reptile would be better suited to a certain niche than reptiles. Perhaps tree-dwelling and eating different food. The reptiles wouldn't go extinct because they are better adapted to some other niche (niches include traits like environment, location, diet, etc.). We don't have to worry about birds as they wouldn't have evolved yet. Once birds come along they will outcompete the reptile-birds as they occupy the same niche (they compete for the same resources). We know this since all reptile-birds are extinct, but it didn't have to be that way, birds theoretically could have occupied a different niche, then the reptile-birds would still be with us.

Different species are adapted for different niches. Niche is probably a word you've heard before too, but I think not a lot of people are clear on what it is. An environmental niche isn't just some physical, geographical spot - I think it's better to think of a niche as a particular way of life, a particular way of interacting with both your physical environment and the other organisms (including members of your own species) in it. Think of crocodiles and alligators - the same for a really long time. Their niche is a freshwater, riverine environment with prey animals in the water and outside of it that come to the banks of the river to drink or to try to cross to the other side. As long as this type of situation continues to exist, so too will crocodiles and alligators. And so far nothing has come along that can live that way of life better than they can.

So, unicellular organisms are very good at a particular way of life, given particular environmental conditions. Some of those conditions are still around. But when there was a mutation (or series of them) that began multicellularity, a whole new way of life was discovered, a way of life that did particularly well under other environmental conditions. Just because some individuals found a way into a new niche doesn't mean the old niche is gone, though.

Edit - ah, I see Golkarian beat me to it with a nice explanation.

Originally Posted by williampinn

So my question is this: Why did the common ancestor survive along with the end species?

Only someone who doesn't understand evolution would ask such a question. There is no such thing as a better species.

The most succesful group is still the prokaryotes and according to your internal mode of thinking they should be nothing but fossils by now.

And resembling the common ancestor doesn't equal to being the common ancestor. You were making leaps in your opening posts as if you were a grasshopper on meth.

Originally Posted by Golkarian

Originally Posted by williampinn

Survival of the fittest? That is a catch phrase I have heard a million times. According to the Darwinian theory, traits that are successful in a given environment are passed on genetically to subsequent generations.

However, every environment has a variety of species. Often times there is at least one species that resembles the common ancestor, perhaps an intermediate species, and an end species.

So my question is this: Why did the common ancestor survive along with the end species? If it is an advantage for reptiles to evolve into birds and mamals, why are there any reptiles left? Obviously a bird/reptile was not more suited to the environment than just a plain old reptile, or the bird/reptile would have survived and the reptile would be extinct--and given enough time, all species would resemble the end species: birds and mamals--even humans--and the common ancestors would fall to the way side. Yet, the single cells we evolved from are still around and living in our environment, and they are well suited, perhaps better suited. So how does the Darwinian theory account for this? Or is there a more modern theory that accounts for it?

I think this is a good question.

My answer is this:

Think about it this way: Wal-Mart comes into town and outcompetes everybody, driving stores out of business. Will it drive farms out of business? No, because, like the reptiles and reptile-birds, they are not competing for the same resources.

The bird-reptile would be better suited to a certain niche than reptiles. Perhaps tree-dwelling and eating different food. The reptiles wouldn't go extinct because they are better adapted to some other niche (niches include traits like environment, location, diet, etc.). We don't have to worry about birds as they wouldn't have evolved yet. Once birds come along they will outcompete the reptile-birds as they occupy the same niche (they compete for the same resources). We know this since all reptile-birds are extinct, but it didn't have to be that way, birds theoretically could have occupied a different niche, then the reptile-birds would still be with us.

That seems to make sense, but I am still wondering why nothing superior to the reptile drove the reptile from its niche. If bird/reptiles continued to evolve in a particular niche and eventually became birds, why did the reptiles stay similar to the common ancestor? Is it possible that evolution is more pronounced when a reptile decides to change niches? That brings me to a new question which I will post seperately since it is a new topic. Thanks for your reply on this topic. :-D

Originally Posted by paralith

Different species are adapted for different niches. Niche is probably a word you've heard before too, but I think not a lot of people are clear on what it is. An environmental niche isn't just some physical, geographical spot - I think it's better to think of a niche as a particular way of life, a particular way of interacting with both your physical environment and the other organisms (including members of your own species) in it. Think of crocodiles and alligators - the same for a really long time. Their niche is a freshwater, riverine environment with prey animals in the water and outside of it that come to the banks of the river to drink or to try to cross to the other side. As long as this type of situation continues to exist, so too will crocodiles and alligators. And so far nothing has come along that can live that way of life better than they can.

So, unicellular organisms are very good at a particular way of life, given particular environmental conditions. Some of those conditions are still around. But when there was a mutation (or series of them) that began multicellularity, a whole new way of life was discovered, a way of life that did particularly well under other environmental conditions. Just because some individuals found a way into a new niche doesn't mean the old niche is gone, though.

Edit - ah, I see Golkarian beat me to it with a nice explanation.

Thanks for your reply anyway. You got me thinking.

Originally Posted by williampinn

That seems to make sense, but I am still wondering why nothing superior to the reptile drove the reptile from its niche. If bird/reptiles continued to evolve in a particular niche and eventually became birds, why did the reptiles stay similar to the common ancestor? Is it possible that evolution is more pronounced when a reptile decides to change niches? That brings me to a new question which I will post seperately since it is a new topic. Thanks for your reply on this topic. :-D

Well, that's also assuming they really are exactly like the common ancestor. I'm no expert on reptile evolution but I imagine most modern day reptiles are probably fairly different from the common ancestor by now. I'm sure there has been competition for their niche, but if they can manage to stay one step ahead they can hold on to it.

It's been pretty clear in evolutionary history that most of the radical changes in groups of organisms happened after a big change in the environment that opened up new niches that were mostly unoccupied before that. That's where a lot of the dramatic change occurs. But like I said, that doesn't mean the other species don't change at all, but they probably do change less if their niche has stayed relatively the same.

Originally Posted by spuriousmonkey

Only someone who doesn't understand evolution would ask such a question.

Yes, people who don't think they know everything ask questions. That makes sense if you stop and thing about it.

Originally Posted by spuriousmonkey

There is no such thing as a better species.

So Darwin was an idiot then? Was he the one who started the rumor that the fittest survive?

Originally Posted by spuriousmonkey

The most succesful group is still the prokaryotes and according to your internal mode of thinking they should be nothing but fossils by now.

No, you misread. According to some evolutionists they should be fossels by now.

Originally Posted by spuriousmonkey

And resembling the common ancestor doesn't equal to being the common ancestor. You were making leaps in your opening posts as if you were a grasshopper on meth.

Well, I never said that resembling a common ancestor equals the common ancestor, thus my use of the adjective "resembling." Obviously one of is on something thinking he/she is on to something.

william, even when Darwin defined fitness, he indicated that it was environment specific. Maybe that's one thing we're missing in this discussion. The definition of fitness is ability to reproduce successfully in a particular environment. There is no animal that is equally fit in all possible environments (though we could argue about us humans and our technologies, of course). A penguin has fantastic fitness when its on the Antarctic coast, but it's very un-fit if if you plop it in the middle of the desert. That's why there is such diversity on earth because different species specialize for different conditions, not for ALL conditions.

Originally Posted by paralith

william, even when Darwin defined fitness, he indicated that it was environment specific. Maybe that's one thing we're missing in this discussion. The definition of fitness is ability to reproduce successfully in a particular environment. There is no animal that is equally fit in all possible environments (though we could argue about us humans and our technologies, of course). A penguin has fantastic fitness when its on the Antarctic coast, but it's very un-fit if if you plop it in the middle of the desert. That's why there is such diversity on earth because different species specialize for different conditions, not for ALL conditions.

I am assuming this is in response to the idea that one species is better than another. Clearly that is the case if one species survives and another becomes extinct, or one species displaces another species in a given niche or environment.

Originally Posted by williampinn

Originally Posted by paralith

william, even when Darwin defined fitness, he indicated that it was environment specific. Maybe that's one thing we're missing in this discussion. The definition of fitness is ability to reproduce successfully in a particular environment. There is no animal that is equally fit in all possible environments (though we could argue about us humans and our technologies, of course). A penguin has fantastic fitness when its on the Antarctic coast, but it's very un-fit if if you plop it in the middle of the desert. That's why there is such diversity on earth because different species specialize for different conditions, not for ALL conditions.

I am assuming this is in response to the idea that one species is better than another. Clearly that is the case if one species survives and another becomes extinct, or one species displaces another species in a given niche or environment.

Well, it all depends on how you measure "better." Is it, how well do individuals of that species reproduce when they're in that environment? That would be fitness. Is it, how long does that species last through evolutionary time? Then that's something else. Definitely if you measure species by longevity some have done much better than others. But that's not entirely due to the qualities of the species itself. Some of that is just luck that the niche they've specialized to has stayed relatively the same for a long time, and if it has changed somewhat since the past, the change was slow enough that they could adapt along with it. If suddenly all the rivers and swamps in the world dried up and disappeared in the space of fifty years, I bet the crocodiles and alligators living in the wild would go extinct.

Survival of the fittest is a term that's quite commonly misunderstood. It means "reproducing things which are well-suited to their environment will tend to reproduce more frequently than things which are less well-suited". Doesn't quite have the same ring to it which is perhaps why Spencer (not Darwin) coined the phrase as a summary. It has been misused and misunderstood ever since. Since both the reproducing things and the environment are constantly changing, having a single species dominate any environment for any significant time is unlikely.

the fact that a species is extinct is not a sure-fire way of assessing their fitness
using that line of reasoning more than 99% of all organisms are unfit because they've died out

when scientists analysed the type of creatures that survived one of the big 5 mass extinctions, they had an incredibly hard time to come up with anything that would make a species extinction-proof - the best they could come up with is that it helps to be widespread and to reproduce fast

conclusion: in that respect rodents, insects and bacteria are high on the list of survival-proofing - maybe it also makes them more fit, i dunno

Originally Posted by williampinn

Originally Posted by paralith

william, even when Darwin defined fitness, he indicated that it was environment specific. Maybe that's one thing we're missing in this discussion. The definition of fitness is ability to reproduce successfully in a particular environment. There is no animal that is equally fit in all possible environments (though we could argue about us humans and our technologies, of course). A penguin has fantastic fitness when its on the Antarctic coast, but it's very un-fit if if you plop it in the middle of the desert. That's why there is such diversity on earth because different species specialize for different conditions, not for ALL conditions.

I am assuming this is in response to the idea that one species is better than another. Clearly that is the case if one species survives and another becomes extinct, or one species displaces another species in a given niche or environment.

I think this is a controversial topic. Some evolutionists like Stephen J. Gould think that while evolution creates better variants (dinosaurs without feathers vs. dinosaurs with feathers), which species survives ultimately (say mammals vs. dinosaurs) is completely subjective and based on random events like asteroid impacts and climate change. According to him if the asteroid did not strike the earth we mammals would still be small nocturnal furballs rather than the nerds of nature we are today, and the dinosaurs would still be dominant. Personally I'm not sure.

I am assuming this is in response to the idea that one species is better than another. Clearly that is the case if one species survives and another becomes extinct, or one species displaces another species in a given niche or environment.

One of the niche creation features is the presence - and concomitant evolution - of other beings.

The appearance of a disease or predator or debilitating parasite or strengthening symbiont or simple physical presence opens up possibilities. In this way, living beings in a landscape sort of bootstrap their way into complexity.

Example: some people think the American Elm is evolving a shrub form - a variety that sets seeds after only a few years, rather than the ten or fifteen the large tree puts into growth before piddling around with a few seeds. This is apparently a consequence of the large tress being killed off before reproduction, by Dutch Elm disease. Now if - as appears to be -the shrub form breeds true, and if - as also appears to be - a few rare larger trees are resistant and will survive to recolonize the depleted canopy of the low lying woods, then in a few centuries (fairly quickly) we will have two species where we had one.

At which time a new environment will have appeared for various insects, fungi, mildews, etc. to spread into and evolve to fit.

Originally Posted by williampinn

Originally Posted by spuriousmonkey

Only someone who doesn't understand evolution would ask such a question.

Yes, people who don't think they know everything ask questions. That makes sense if you stop and thing about it.

Originally Posted by spuriousmonkey

There is no such thing as a better species.

So Darwin was an idiot then? Was he the one who started the rumor that the fittest survive?

No, you are for thinking you understand what Darwin wrote. Read his book first.

William,
in his inimicable style Spurious is pointing out, as have others, that fitter and better are not synonyms.

Better has implications of superiority, of higher quality. That has little or nothing to do with survival in a specific niche at a specific time by a specific......hmmm....species.

Originally Posted by marnixR

the fact that a species is extinct is not a sure-fire way of assessing their fitness

I agree. It is a sure-fire way of assessing their unfitness.

Originally Posted by marnixR

using that line of reasoning more than 99% of all organisms are unfit because they've died out

Yes, when organisms are unfit they die.

Originally Posted by marnixR

when scientists analysed the type of creatures that survived one of the big 5 mass extinctions, they had an incredibly hard time to come up with anything that would make a species extinction-proof - the best they could come up with is that it helps to be widespread and to reproduce fast

Fitness could be relative rather than absolute, but microbes and insects have done very well given the fact they are widely spread and can reproduce quickly and in great numbers.

Originally Posted by marnixR

conclusion: in that respect rodents, insects and bacteria are high on the list of survival-proofing - maybe it also makes them more fit, i dunno

Or maybe they are low on the list of survival-proofing and high on the list of "extinction-proofing."

Originally Posted by spuriousmonkey

No, you are for thinking you understand what Darwin wrote. Read his book first.

You mean the book you haven't read? Well, let's assume arguendo that you have read his book. What did you think about the part about the finches? And why on Earth would you even imagine that Darwin declared in his book or at any other time that he believed that the unfittest survive over the fittest?

Pop quiz: Do you even know the title of Darwin's book? I will give you a clue: it wasn't "Survival of the Unfittest" or "Origin of the Penguin Fishes."

Originally Posted by Ophiolite

William,
in his inimicable style Spurious is pointing out, as have others, that fitter and better are not synonyms.

It is irrelevant whether "better" and "fitter" are synonyms. Better is an adjective. For example: One species has better fitness than another for one or more niches. It is therefore better by the fitness standard. M-kay?

Originally Posted by Ophiolite

Better has implications of superiority, of higher quality.

Wow! I learn something new everyday.

Originally Posted by Ophiolite

That has little or nothing to do with survival in a specific niche at a specific time by a specific......hmmm....species.

You are so right! Just because one species survives over another does not mean it has any superiority by the standard of fitness. In fact it is inferior!

Alright people, enough ad hominem about who's read what, and the general snarkiness going around. Really what Darwin wrote is immaterial to this discussion anyway, since the definition of fitness stands no matter what was in the Origin of Species. I don't think anyone is fundamentally disagreeing here.

Fitness is specific to environment. If the environment a group of organisms has adapted to changes suddenly, the organisms are now in an environment in which they are unfit. Unless they can quickly evolve to the environment and re-gain their fitness, they will die out due to this unfitness to the new environment. I think we can all agree on this.

Originally Posted by paralith

Fitness is specific to environment. If the environment a group of organisms has adapted to changes suddenly, the organisms are now in an environment in which they are unfit. Unless they can quickly evolve to the environment and re-gain their fitness, they will die out due to this unfitness to the new environment. I think we can all agree on this.

I agree with this. I also think it is possible for one species to be better than another by many different standards incuding fitness. That shouldn't be a big deal, nor is it, as you pointed out, cause for debate, since it doesn't prejudice the concept of fitness.

I sincerely apologize for my snarky input. Hopefully others will be big enough to post their apologies also. :-D

It is a common misconception among those not educated in biological sciences that "fitness" is a measure between organisms.

This isn't the case. The fitness of an organism is measured against its specific environment, which includes habitat and climate. Organisms that are the "fittest" are successful in passing their DNA to children who are able to reproduce. Organisms that do not pass DNA in this fashion or do so inconsistently enough to maintain a breeding population are "less fit" when measured against their environment.

Now that you've been sufficiently educated on biological fitness, was there a new topic you wanted to raise with regard to evolution? I'm happy to discuss primate evolution. I'm sure others are willing to discuss other facets of evolution.

Originally Posted by SkinWalker

It is a common misconception among those not educated in biological sciences that "fitness" is a measure between organisms.

This isn't the case. The fitness of an organism is measured against its specific environment, which includes habitat and climate. Organisms that are the "fittest" are successful in passing their DNA to children who are able to reproduce. Organisms that do not pass DNA in this fashion or do so inconsistently enough to maintain a breeding population are "less fit" when measured against their environment.

Now that you've been sufficiently educated on biological fitness, was there a new topic you wanted to raise with regard to evolution? I'm happy to discuss primate evolution. I'm sure others are willing to discuss other facets of evolution.

Your education is apparently missing an important element: fitness is a measure between organisms for two reasons: one could compare two organisms to see which is more fit for a specific environment. Also, organisms often compete with each other, so the fitness of an organism is, among other things, measured against other organisms in that context.

Another thing you might want to add to your education is a better understanding of what an "environment" is. It is not some nebulous floating abstraction. The broadest definition of "evironment" I have seen thus far includes everything an organism might encounter or interact with--that includes other organisms. It could even include cosmic rays...

:-D

Originally Posted by williampinn

I sincerely apologize for my snarky input. Hopefully others will be big enough to post their apologies also. :-D

i will not apologise for snarky comments in my post since no snarkiness was intended
on the other hand, if someone wilfully aims to misrepresent what i have stated i know that it's time for me to leave the discussion

however, one parting shot william: you use the word "fit" as the type of fitness you get from the gym, whereas many others in the discussion use in the sense of how your hand fits in a glove

is my hand in some way better than that of my wife because it fits my glove better than it does hers ?

william, I see you repentance was short lived since your attitude has come right back out. Marnix I understand your viewpoint, and I didn't think you were snarking either, but if I see anymore snarking or more of this off-topic back and forth this thread is done.

Originally Posted by marnixR

is my hand in some way better than that of my wife because it fits my glove better than it does hers ?

Your hand is definitely better at fitting YOUR glove. When I say a species has better fitness or is more fit, I am making an apples-to-apples comparison. You can infer this if you pay attention to the context.

Originally Posted by paralith

william, I see you repentance was short lived since your attitude has come right back out. Marnix I understand your viewpoint, and I didn't think you were snarking either, but if I see anymore snarking or more of this off-topic back and forth this thread is done.

I apologized for my intended sarcasm. Any further snarkiness was not intended, so no apology this time. Even my intentional sarcasm was in self-defense against an ad hom. I never start fights and I don't look for trouble, but like Cyrano, I can outwit and out-flank anyone who is. Plus, I have enough class to be the bigger man and apologize. It's a thing called maturity. Anyway, I am bored watching illiterates rape the English language and then try to make a pissing contest out of it. Bye.

This thread is locked. In the future, just do this: no snarking, no sarcasm, no off topic rants on apologies and who deserves what and being talked down to, etc etc.

Stick to the science. That goes to anyone who's listening.

Originally Posted by williampinn

Your education is apparently missing an important element: fitness is a measure between organisms for two reasons: one could compare two organisms to see which is more fit for a specific environment. Also, organisms often compete with each other, so the fitness of an organism is, among other things, measured against other organisms in that context.

Another thing you might want to add to your education is a better understanding of what an "environment" is. It is not some nebulous floating abstraction. The broadest definition of "evironment" I have seen thus far includes everything an organism might encounter or interact with--that includes other organisms. It could even include cosmic rays...

:-D

You are correct. In this context other organisms are part of the environment, as you say. But, more to my point, the fitness of one organism isn't necessarily relative to that of another in that one must be superior to another, more advanced, etc. This can, of course, happen. It just isn't necessary to define fitness.

This is why we still have gibbons and baboons as well as apes like gorillas and chimps. Homo sapiens aren't "superior" species if tossed naked in the middle of a Savannah. Baboons are. But the superiority is relative to the environment. Put a baboon and a human in a city, and the human stands a better chance of producing offspring that reproduce. Put them both on a savannah, and the reverse occurs.

Thus, fitness is measured by the organisms success in an environment, which includes intra- and inter-species competition. It's very likely, for instance, that early primates in North America and Europe were out-competed by frugivorous bats, whose remains become dominant in the fossil record of the Eocene.