[quote name='Khaiy' timestamp='1296857586' post='4769743']
I assume you're responding to my post responding to mikeman. My point in that post was that cancer is not a problem of non-cancerous cells in the vicinity of cancerous ones being not competetive enough, as increased competition from other cells would be worse than cancer, not better, because once cells fight amongst each other for resources the destruction of the host organism is guaranteed.

The sharing DNA part is a pretty big consideration to consider things "apart" from. But here's my reasoning:

1. Resources don't have anything to do with the reproductive advantage of a cancerous cell, nor do they compete any better for the resources that are there. You can make the argument (as you are) that the abundance of resources in a human body coupled with the lack of interest of the top-down control structure in managing cancerous cells creates a very special niche which any cell can exploit by reproducing a ton, but.

2. Unlike organisms in a given environment, cells have very specific functions.

2a. All functions of all cells are expressly for the continuation of the overall organism, with the payoff for the cells being the continued introduction of resources. As soon as cancer develops, it guarantees that this process will end. A cell line could continue forever if the organism continued to thrive, and even though cancer isn't the only possible end to thriving, the organism doesn't move past it. It's only in the last few decades that many people have lived long enough to die of cancer, but if you live long enough you will develop it, and if nothing else kills you, cancer will.

3. Genetic traits are not limited to a single organism. If you look at the lineage of cells through generations of organisms, non-cancerous cells are vastly more numerous than cancerous ones. Genetic similarity of parent to child declines by half with each generation, but one genetic difference that is never passed from one generation to the next is an inferior copy of (or lack of) the p53 and RAS oncogenes. Cancerous cells are not more successful at persisting through time and through successive generations than non-cancerous ones.

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1. Yes they do.
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I could have been clearer here. The cancerous cells do indeed need resources to reproduce. But they do not have any better access to resources, are not better at absorbing or using them, than any other cells. The reason that they reproduce more is not based on resources-- the level of resources that they have access to is pretty consistent over time, and cetianly the same as non-cancerous cells.

2. So do organisms in an environment.
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False. Organisms in an environment fill a niche, which is controlled by probabilities and a normal distribution of variants on existing organisms. An organism takes its place in a dynamic equilibrium, but they do not exist nor have have they evolved to serve a single (or set) of function(s). As conditions in an environment change, you can see a change in relative frequencies of traits in a species in response. Cells in your body are the same and perform the same functions in the same way regardless of other factors.

2.a. No they are not. A liver cell does not think, "Oh damn this dude is drinking a lot so I better work extra hard so he can feel good and every cell in the body can live longer," it just does it's job. For all it knows it could be outside the body as long as it's still getting everything it needs to survive. It just so happens that what it does is beneficial to the whole system and the whole organism can live longer.
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You're arguing my point, particularly with your statement that cells have "jobs" and that they will continue to do those jobs "as long as [they] are still getting everything [they] need to survive". It does not "just so happen" that cellular functions benefit the overall organism. Organs are refinements of precursor structures that existed in ancestors of a current organism. Their functions have been refined because they benefit the entire organism, allowing it to reproduce more or better. A liver that's better at being a liver doesn't do anything for the liver itself, because it's only at the organismal level that function brings extra resources or other measures of fitness. No, a liver does not "think", because thinking is irrelevant. A liver that is less effective reduces fitness of the organism that contains it, and is less likely to be passed on.

3. They do in the sense of a body being the environment. If we over-reproduced and killed our planet by using up or blowing up all the resources we would all die just like cancer cells die when the body dies.

You are still looking at cells as cells. To understand the analogy look at a cell as an organism and the body as the environment.
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Cells are cells. No matter how nice or convenient your analogy might be for your point, cells are like cells more than they are like anything else, because they are cells. An analogy that requires they shed their cell-like characteristics to be replaced by some other characteristics is going to break down at some point, and we've certainly reached that here. I understand your analogy, but it doesn't work at the level of precision you're trying to apply. Cells cannot reproduce independently of the overall body, and cannot even live independently. A squirrell can move from one ecosystem to another if it feels like it. Your pancreas cannot.

You seem like you're a big proponent of Lovelock. If you really like the idea of Gaiaology then go ahead and frame things that way. But cells are part of a finite open system, and contain the entire genome of that system, and are streamlined (more or less) by statistical considerations such that a type of cell behaves in one way, essentially static. The earth is a massive closed system, with incredible dynamic forces on genetic diversity regardless of current conditions. There are so many differences between the earth and a human body that repeating "They're the same, just think about them as if they were the same" isn't going to cut it.

Plus, life on the earth has (and will continue to) recover from a lot-- even if you think that the earth "lives", it certainly doesn't do so in any way similar to the organisms on it. Life continues on the planet after dramatic events like mass extinctions, and niches that are left vacant for any reason will eventually be filled by something, even if it's just a novel kind of bacterium.

If, as you seem fond of repeating, humans over-used resources to the point that the planet could no longer sustain human life, that wouldn't be the end of life on Earth. Our corpses would leave ample material for other organisms, be they scavenging animals or humble bacteria. Even if humans ate all of the food that we can eat, the feces we produced would nourish record numbers of microorganism species, whether or not the humans continued on. Will that happen with the cells in your body? Of course not. Once the organism dies, everything that made it up will die, despite the presence of the same abundance of material resources.

[quote name='Khaiy' timestamp='1296857586' post='4769743']
If you want to look at a single organism at a time, you can look at cancerous cells as superior in the sense that they reproduce faster. But they are not different from other cells in any other "competitive" capacity. And the strategy that they follow is not possible in any environment other than the one that they inhabit, which is almost entirely absent of selection pressures. So any analogy that you make to other environments isn't going to go very far, because no other environment is like a multicellular organism.

Faster reproduction is a HUGE competitive advantage. It's absolutely astronomical in how big a competitive advantage it is.
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Faster reproduction is indeed a successful strategy in many situations (although not a cut-and-dried "advantage"). However, cells that make up an organism do not compete with each other as different organisms do. Reproductive and genetic factors do not apply to cells in an organism in the same ways that they do amongst organisms, because they do not reproduce in the same way nor do they face tests of fitness in the same way.

and I'm not so sure you have argued quite well enough to nullify the Terrestrial organisms:Earth::Cells:People analogy. Every organism serves it's purpose in the environment of the earth.
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See above for clarification, I don't want to re-type why Gaiaology and a dynamic equilibrium of limitless types of organisms responding to shifting conditions at any given time is different from organism-level fitness enforcing specific behaviors on limited varieties of cells in symbiotic-style communities. Your position oversimplifies the concepts evolution and population biology while mis-applying them. If your position reflected the reality of natural selection or population biology, then I might agree with your conclusion that cancerous cells are more fit because they reproduce more. But your position does not reflect the realities of those things.

1. Yes they do.

I could have been clearer here. The cancerous cells do indeed need resources to reproduce. But they do not have any better access to resources, are not better at absorbing or using them, than any other cells. The reason that they reproduce more is not based on resources-- the level of resources that they have access to is pretty consistent over time, and cetianly the same as non-cancerous cells.[/quote]
If you look at cancerous cells and healthy cells. The cancerous cells consume more resources than healthy cells because there are more of them. If there were no resources, they would not continue reproducing because they would not have the resources with which to make a new cell.

2.a. No they are not. A liver cell does not think, "Oh damn this dude is drinking a lot so I better work extra hard so he can feel good and every cell in the body can live longer," it just does it's job. For all it knows it could be outside the body as long as it's still getting everything it needs to survive. It just so happens that what it does is beneficial to the whole system and the whole organism can live longer.
[/quote]

You're arguing my point, particularly with your statement that cells have "jobs" and that they will continue to do those jobs "as long as [they] are still getting everything [they] need to survive". It does not "just so happen" that cellular functions benefit the overall organism. Organs are refinements of precursor structures that existed in ancestors of a current organism. Their functions have been refined because they benefit the entire organism, allowing it to reproduce more or better. A liver that's better at being a liver doesn't do anything for the liver itself, because it's only at the organismal level that function brings extra resources or other measures of fitness. No, a liver does not "think", because thinking is irrelevant. A liver that is less effective reduces fitness of the organism that contains it, and is less likely to be passed on.[/quote]
organisms fill a role in the environment too. Plants make O2, without which most other life would die. Spiders eat flys, without which we'd have an overabundance of flies who would consume the food the rest of the body is dependent on.

We have controls that more specifically dictate which roles our cells take on, but the role of a cell in comparison to a human is very similar. The cell depends on every piece doing its function as well as each piece depending on the cell to do its function. If either stops, both die.

3. They do in the sense of a body being the environment. If we over-reproduced and killed our planet by using up or blowing up all the resources we would all die just like cancer cells die when the body dies.

You are still looking at cells as cells. To understand the analogy look at a cell as an organism and the body as the environment.
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Cells are cells. No matter how nice or convenient your analogy might be for your point, cells are like cells more than they are like anything else[/quote]
Oh I get it. Your argument is that analogies and metaphors are stupid.

Disregard previous points as I should have just ignored you in the first place.

[quote name='Khaiy' timestamp='1297180266' post='4771381']

1. Yes they do.

I could have been clearer here. The cancerous cells do indeed need resources to reproduce. But they do not have any better access to resources, are not better at absorbing or using them, than any other cells. The reason that they reproduce more is not based on resources-- the level of resources that they have access to is pretty consistent over time, and cetianly the same as non-cancerous cells.[/quote]

If you look at cancerous cells and healthy cells. The cancerous cells consume more resources than healthy cells because there are more of them. If there were no resources, they would not continue reproducing because they would not have the resources with which to make a new cell.[/quote][/quote]

But per cell absorption rates are identical. When the first cancer cell becomes a cancer cell, it reproduces despite taking in exactly the same amount and types of resources as a non-cancerous cell. Its reproductive ability isn't because it's better at getting or using energy, but because of an entirely seperate trait that removes limits on when it reproduces, and another trait that stops the aberrant cell from being destroyed.

But my position isn't that you can't compare the reproductive rates of cells and determine that one is better at reproducing than the other. As I posted above, there are other factors in a multicellular organism which make a simple comparison of resource allocation by groups of cells a less useful comparison to make than it is between different species in an ecosystem.

2.a. No they are not. A liver cell does not think, "Oh damn this dude is drinking a lot so I better work extra hard so he can feel good and every cell in the body can live longer," it just does it's job. For all it knows it could be outside the body as long as it's still getting everything it needs to survive. It just so happens that what it does is beneficial to the whole system and the whole organism can live longer.
[/quote]

You're arguing my point, particularly with your statement that cells have "jobs" and that they will continue to do those jobs "as long as [they] are still getting everything [they] need to survive". It does not "just so happen" that cellular functions benefit the overall organism. Organs are refinements of precursor structures that existed in ancestors of a current organism. Their functions have been refined because they benefit the entire organism, allowing it to reproduce more or better. A liver that's better at being a liver doesn't do anything for the liver itself, because it's only at the organismal level that function brings extra resources or other measures of fitness. No, a liver does not "think", because thinking is irrelevant. A liver that is less effective reduces fitness of the organism that contains it, and is less likely to be passed on.[/quote]

organisms fill a role in the environment too.

Plants make O2, without which most other life would die. Spiders eat flys, without which we'd have an overabundance of flies who would consume the food the rest of the body is dependent on.

We have controls that more specifically dictate which roles our cells take on, but the role of a cell in comparison to a human is very similar. The cell depends on every piece doing its function as well as each piece depending on the cell to do its function. If either stops, both die.[/quote]

Keyword above being "most". The earth in no way requires oxygen to feature life, and if all oxygen producers died life would continue (although obviously not the oxygen-dependant life). Your body does not have this luxury. If there is a failure in some important group of cells in your body, nothing will fill the gap. You will die. If an ecological niche is being underutilized, a normal distribution of organism traits and behaviors will end up producing groups that fill that niche. If the environment changes, the same thing takes place with organisms adapting to fit the new environment. There is no control on this, it's a statistical phenomenon. But life on Earth will not end in a situation where an important species dies or leaves. In a comparable situation, life in your body will end.

Yes, spiders eat flies, and without them we would have a lot of flies for something else to eat, or that would starve because there are not enough resources to nourish them. Either way, there would still be flies. WIthout spiders, lots of flies for a while and then less flies again back into balance. Spiders vanishing does not lead to all flies perishing, although it can throw the ecosystem out of balance to an extent that could potentially produce that result. This is not the case in your body.

3. They do in the sense of a body being the environment. If we over-reproduced and killed our planet by using up or blowing up all the resources we would all die just like cancer cells die when the body dies.

You are still looking at cells as cells. To understand the analogy look at a cell as an organism and the body as the environment.
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Cells are cells. No matter how nice or convenient your analogy might be for your point, cells are like cells more than they are like anything else[/quote]

Oh I get it. Your argument is that analogies and metaphors are stupid.

Disregard previous points as I should have just ignored you in the first place.
[/quote]

No need to be a jerk, 2lazy. Analogies are fine and good, but if they are your only piece of evidence, you have a problem with your argumentation. If you start from the assumption that the things that make cells different from organisms are irrelevent, then fine, your analogy will hold to support your point if you are correct. What I'm saying is that the differences you're simply ignoring are not insignificant, but rather render the analogy not suitable for supporting your point. Rather than re-stating your analogy, you could elaborate on why the dissimilarities I'm trying to describe are not as significant as I think, or provide other evidence supporting your idea.

And why bother to post explicitly that you should just be ignoring me? You clearly already are, picking a few responses I give, responding to them by repeating your position but not supporting it, and then ignoring the other points I made that are contrary to your position.

No need to be a jerk, 2lazy. Analogies are fine and good, but if they are your only piece of evidence, you have a problem with your argumentation.

back to the individual thing i was replying to:

"If you think of it that way, the problem is in the immune system of the organism. But an organism is not an ecosystem in the sense that other environments are, where individuals compete for resources to gain reproductive advantage. An organism is a large and complex set of symbiotic relationships, and if a given cell goes rogue it would be up to processes directed at the organismal level to deal with it, not any direct cell-to-cell interaction. "

And then you gave these examples trying to support it:

1. Resources don't have anything to do with the reproductive advantage of a cancerous cell, nor do they compete any better for the resources that are there. You can make the argument (as you are) that the abundance of resources in a human body coupled with the lack of interest of the top-down control structure in managing cancerous cells creates a very special niche which any cell can exploit by reproducing a ton, but...

2. Unlike organisms in a given environment, cells have very specific functions.

2a. All functions of all cells are expressly for the continuation of the overall organism, with the payoff for the cells being the continued introduction of resources. As soon as cancer develops, it guarantees that this process will end. A cell line could continue forever if the organism continued to thrive, and even though cancer isn't the only possible end to thriving, the organism doesn't move past it. It's only in the last few decades that many people have lived long enough to die of cancer, but if you live long enough you will develop it, and if nothing else kills you, cancer will.

3. Genetic traits are not limited to a single organism. If you look at the lineage of cells through generations of organisms, non-cancerous cells are vastly more numerous than cancerous ones. Genetic similarity of parent to child declines by half with each generation, but one genetic difference that is never passed from one generation to the next is an inferior copy of (or lack of) the p53 and RAS oncogenes. Cancerous cells are not more successful at persisting through time and through successive generations than non-cancerous ones.[/quote]

1. Again they totally do. The cancer uses more resources including space as a resource that eventually makes some other cells incapable of serving their function. This happens in nature with organisms too. The Zebra mussel being a great example.

2. So do a lot of organisms. In an ecosystem almost every organism serves very specific functions. Sometimes more than one organism serves similar functions, which also happens in the body, but they all serve functions to the ecosystem.

your second response to 2.a.

False. Organisms in an environment fill a niche, which is controlled by probabilities and a normal distribution of variants on existing organisms. An organism takes its place in a dynamic equilibrium, but they do not exist nor have have they evolved to serve a single (or set) of function(s). As conditions in an environment change, you can see a change in relative frequencies of traits in a species in response. Cells in your body are the same and perform the same functions in the same way regardless of other factors.[/quote]

Cells in your body do perform differently and die dependent on outside factors and changes in the environment.

3. This is not relevant to the analogy.

edit: the largest difference is that the human body has DNA as a blueprint to set up a balanced and mutually beneficial ecosystem for its cells, but even that doesn't nullify the analogy.

They are still some larger whole constructed of smaller pieces each filling a specific role in the perpetuation of the whole by perpetuating its own line through some form of multiplication/reproduction.

[quote name='Khaiy' timestamp='1297187054' post='4771424']
No need to be a jerk, 2lazy. Analogies are fine and good, but if they are your only piece of evidence, you have a problem with your argumentation.

back to the individual thing i was replying to:

"If you think of it that way, the problem is in the immune system of the organism. But an organism is not an ecosystem in the sense that other environments are, where individuals compete for resources to gain reproductive advantage. An organism is a large and complex set of symbiotic relationships, and if a given cell goes rogue it would be up to processes directed at the organismal level to deal with it, not any direct cell-to-cell interaction. "

And then you gave these examples trying to support it:

1. Resources don't have anything to do with the reproductive advantage of a cancerous cell, nor do they compete any better for the resources that are there. You can make the argument (as you are) that the abundance of resources in a human body coupled with the lack of interest of the top-down control structure in managing cancerous cells creates a very special niche which any cell can exploit by reproducing a ton, but...

2. Unlike organisms in a given environment, cells have very specific functions.

2a. All functions of all cells are expressly for the continuation of the overall organism, with the payoff for the cells being the continued introduction of resources. As soon as cancer develops, it guarantees that this process will end. A cell line could continue forever if the organism continued to thrive, and even though cancer isn't the only possible end to thriving, the organism doesn't move past it. It's only in the last few decades that many people have lived long enough to die of cancer, but if you live long enough you will develop it, and if nothing else kills you, cancer will.

3. Genetic traits are not limited to a single organism. If you look at the lineage of cells through generations of organisms, non-cancerous cells are vastly more numerous than cancerous ones. Genetic similarity of parent to child declines by half with each generation, but one genetic difference that is never passed from one generation to the next is an inferior copy of (or lack of) the p53 and RAS oncogenes. Cancerous cells are not more successful at persisting through time and through successive generations than non-cancerous ones.[/quote][/quote]

1. Again they totally do. The cancer uses more resources including space as a resource that eventually makes some other cells incapable of serving their function. This happens in nature with organisms too. The Zebra mussel being a great example.[/quote]

As I posted, you can make this argument. But there are other factors which are very different between a multicellular organism and a multi-organism ecosystem, which are discussed below.

2. So do a lot of organisms. In an ecosystem almost every organism serves very specific functions. Sometimes more than one organism serves similar functions, which also happens in the body, but they all serve functions to the ecosystem.[/quote]

First, organisms don't serve specific functions. They exploit opportunities. This may seem like a trivial difference, but it's not. It makes no difference to an ecosystem what goes on inside of it. As long as some balance is reached, it doesn't really matter what that balance is. If a type of organism goes extinct, it might alter the balance, even dramatically so, but it's unlikely to destroy all life in that area. Certain organisms might be useful given a current composition of organisms in an environment, but the composition can and does change; in fact, it's generally not static to begin with.

The body of an organism isn't the same. It is a closed system as far as composition. Your cells are present because they serve a specific function, like transmitting current to contract muscles or regulating internal temperature. They operate solely for the benefit of the other cells in the organism, to promote success of the organism If you take those out, the whole organism will die. If you remove a species from an ecosystem, something may be lost, but all that will happen is that the species composition will change. An organism exerts direct control over functions of cells, sending a chemical signal to prompt reproduction, for example. An ecosystem does no such thing.

So I might amend my statement to say that cellular functions are necessary to a body, but organismal functions are not necessary to an environment. A body directly controls its cells, but an ecosystem does not. These are significant differences between an organism and an ecosystem.

your second response to 2.a.

False. Organisms in an environment fill a niche, which is controlled by probabilities and a normal distribution of variants on existing organisms. An organism takes its place in a dynamic equilibrium, but they do not exist nor have have they evolved to serve a single (or set) of function(s). As conditions in an environment change, you can see a change in relative frequencies of traits in a species in response. Cells in your body are the same and perform the same functions in the same way regardless of other factors.[/quote]

Cells in your body do perform differently and die dependent on outside factors and changes in the environment.[/quote]

There is not a distribution of function between cells of a given type. One liver cell works the same as the next, unless one is damaged. If conditions change, say the internal temperature of a body increases beyond the optimal range for liver cell operation, they all suffer the same effects. No change in cell composition takes place to adjust to the new condition because an organism so heavily discourages variation from cell to cell of the same type. Traits of those cells don't change. An organism strives to maintain as consistent an environment as possible because it lacks this variation, and operates explicit controls to affect the activity of its constituent cells. Ecosystems do not participate in system-wide regulation, for perpetuation of the system or any other purpose.

3. This is not relevant to the analogy.[/quote]

A body has a guaranteed end, while an ecosystem does not. An ecosystem is successful when its composition can change, and the balance within change as well. A body is successful when its composition is steady, and it proactively resists change. My point in #3 the closed system, finite timespan, and active inhibition of variation between constituent cells in an organism is a marked departure from an ecosystem. And because genetic differences, unlimited timespan, and open nature of ecosystems are what drive the dynamic equilibria within them that the comparison is not a very precise one. In altering the organism example I tried to sharpen the analogy to be more precise to terrestrial species:Earth one.

edit: the largest difference is that the human body has DNA as a blueprint to set up a balanced and mutually beneficial ecosystem for its cells, but even that doesn't nullify the analogy.

They are still some larger whole constructed of smaller pieces each filling a specific role in the perpetuation of the whole by perpetuating its own line through some form of multiplication/reproduction.
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I think that there are other differences which are similarly large, or at least similarly important, which I have tried to describe above. These differences, along with the common DNA difference you cite, are great enough and significant enough that I dispute the use of concepts applicable on one scale to the other.

cut for length

Your differences are trivial to the analogy and missing the point though.

Despite the fact that a lot of what you say about ecosystems generalizes about ecosystems on a global scale, ecosystems can respond just as poorly as a human system if an organism/organ stopped functioning or was removed.

It just so happens that after millions of years our ecosystem is at a state where it has hundreds of species working towards similar roles. If you want another good example, people are flipping balls because of bees dying totally changing our ecosystem. That's with millions of species on the planet vs the couple hundred distinct cell types in the human body.

A more accurate example to an organ failing would be the entirety of a phylum going extinct in a short period of time, which would result in the death of a whole crapload of things.

edit: also, "[color=#1C2837][size=2]A body has a guaranteed end, while an ecosystem does not," is not necessarily true.

[quote name='Khaiy' timestamp='1297204440' post='4771569']
cut for length

Your differences are trivial to the analogy and missing the point though.

Despite the fact that a lot of what you say about ecosystems generalizes about ecosystems on a global scale, ecosystems can respond just as poorly as a human system if an organism/organ stopped functioning or was removed.[/quote]

An ecosystem can respond as poorly as a humany body, as in the case of a dead zone. But if you remove a species from an ecosystem, it almost certainly will not kill everything in it forever. The response to a loss of organ function not only can be the death of every single component within that organism, but that will be the case.

If you want to look at the entire planet as a single ecosystem, that's a diffiuclt leap to make, particularly comparing it to the function of a single organism. Is your position that the analogy is meant to apply on a global scale only?

It just so happens that after millions of years our ecosystem is at a state where it has hundreds of species working towards similar roles. If you want another good example, people are flipping balls because of bees dying totally changing our ecosystem. That's with millions of species on the planet vs the couple hundred distinct cell types in the human body.

A more accurate example to an organ failing would be the entirety of a phylum going extinct in a short period of time, which would result in the death of a whole crapload of things.[/quote]

Emphasis above added by me. Changing an ecosystem is very different from the complete destruction of life in that ecosystem.

As for a phylum's sudden extinction, it most certainly could affect a whole crapload of things. But it does not result in the extinction of everything, particularly at the global scale where you have ecosystems that are not connected to each other at all. And why even limit it to suddenness? If a person's kidneys fail over four decades, and nothing else kills him, kidney failure will absolutely will. This is not the case with the disappearence of a phylum, either globally or with all representatives of a phylum in a local area.

Mass extinctions happen periodically. The earth has not become barren and lifeless as a result, even temporarily.

edit: also, "[color="#1c2837"]A body has a guaranteed end, while an ecosystem does not," is not necessarily true.
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In what sense? As bodies currently operate, they do not last forever. They eventually cease to live, regardless of other factors. Do you mean that ecosystems are guaranteed to end?

I guess that my overarching point is that organisms in an ecosystem, whether you define it globally or locally, do not depend on that ecosystem in the same way that cells depend on their overall organism. Ecosystems do not manage their constituents like organisms do. While there are absolutely similarities between an organism and an ecosystem, those similarities are not so numerous or significant as to declare that reproductive prowess is driven by the same mechanisms or possesses the same significance in an organism compared to an ecosystem.

I guess that my overarching point is that organisms in an ecosystem, whether you define it globally or locally, do not depend on that ecosystem in the same way that cells depend on their overall organism. Ecosystems do not manage their constituents like organisms do. While there are absolutely similarities between an organism and an ecosystem, those similarities are not so numerous or significant as to declare that reproductive prowess is driven by the same mechanisms or possesses the same significance in an organism compared to an ecosystem.

Then we'll have to agree to disagree.

The body is not a macro-ecosystem like our planet, but a lot of what happens in nature between organisms happens inside our body. If you are going to let the difference between filling a niche and doing a job destroy the metaphor fine. As far as I am concerned you read way too far into a simple analogy.