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Why are our supposed ancestors extinct?


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No, we're not more evolved, because there's no such thing as "more evolved." And there is no "trunk" vs. "branches," it's just a split. And modern monkeys are about as different from our common ancestor as we are. However, there's no reason they "should" be. There's no reason different species can't change at different rates. Horseshoe crabs have changed very little in the last 450 million years, presumably because very few incremental changes have been especially useful to them, and the population has been large enough to even out most random drift.

 

Perhaps "more evolved" in the sense of having accumulated more changes since the fork than the other side of the fork. Certainly not "more advanced". I would expect that when a species forks, with one fork remaining in the prior environment and the other fork spreading into a new/different environment, one would expect the latter fork to "evolve more" in the sense that its different environment would lead to more opportunities for successful mutations.

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I would expect that when a species forks, with one fork remaining in the prior environment and the other fork spreading into a new/different environment, one would expect the latter fork to "evolve more" in the sense that its different environment would lead to more opportunities for successful mutations.

This may be true but it does not equal an increase in genetic information, though (if that is what is implied). Adaptation to a new environment can also result in the loss of now unnecessary genes. A prime example are certain parasitic organisms (especially bacteria) that generally have a smaller genome than their free-living cousins.

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This may be true but it does not equal an increase in genetic information, though (if that is what is implied). Adaptation to a new environment can also result in the loss of now unnecessary genes. A prime example are certain parasitic organisms (especially bacteria) that generally have a smaller genome than their free-living cousins.

 

I'm not implying an increase in genetic information, only that one might observe a greater number of differences. For example, consider a population of fish moving into a lightless cave environment. Mutations that affected eye development (up to and including deletion of eyes altogether) are no longer selected against, and thus those differences from the related fish outside can accummulate. Perhaps the cave water is also colder, and thus mutations that adapt the fish to colder waters are also now beneficial. And perhaps the bugs that the fish eat are different inside the caves, or require a slightly different feeding behavior: again, there is an opportunity for improvement (in fitness) if beneficial mutations occur.

 

In general terms, if the population is in a new environment (or the environment has recently changed) such that the population is not already highly adapted to the environment, then it is more likely that mutations will be beneficial as compared to the population that is already highly adapted. For the population that is highly adapted, few changes would improve adaptation further, so nearly all changes will be neutral or detrimental.

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I see. Well, I just wanted to make the point that adaptation can equally mean the loss of traits rather than addition of new ones. In many threads (or in real life) often associate differences with additional abilities, novel mutations, etc. and neglect the fact that the reverse can also occur. But from your other posts I should have known that quite clearly this was not the case here. My bad.

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I see. Well, I just wanted to make the point that adaptation can equally mean the loss of traits rather than addition of new ones. In many threads (or in real life) often associate differences with additional abilities, novel mutations, etc. and neglect the fact that the reverse can also occur. But from your other posts I should have known that quite clearly this was not the case here. My bad.

 

Still a good point, and no offense taken. :)

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yes i know, but what i'm saying is that, when a

notify family is the only one which started life.

 

there was no other surname on earth for my aunt to marry from.

 

you follow me?

It was an analogy, not a model. Your argument is actually a Strawman (http://en.wikipedia.org/wiki/Straw_man).

 

Yes, the analogy is not perfect (if it was it would be a model). Yes, in the real world there would not have been another "surname" so to speak, but if you look at what I said as an analogy, then the other "Surname" is just the group of individuals that are starting to separate from the individual with "your surname". In that respect, my analogy holds.

 

As my answer was framed for someone who was looking for understanding of how it could occur, rather than trying to push "Evolution can not occur and I will twist any analogy to prove the model can't work", then I obviously completely misunderstood your motives for positing. This was why my answer was not a refutation of a position.

 

I was not arguing a point, I was explaining.

 

So as a counter argument to your point (evolution means that one species can't separate into two or more species):

 

1) Groups of animals of a species do not have an identical genetic code. There exist differences even within a population of animals.

 

2) If this population is spread out over a large area, then the environment will be different across the range of this species.

 

3) Because there exist differences within the environments that this species ranges, it means that there will be different evolutionary pressures on the different parts of this species.

 

4) Because of this, the population of animals will start to become more and more differentiated in their genetic code.

 

5) Eventually, because each group within the species is becoming more specialised, then cross breeding between the groups will produce less specialised individuals and these will not be as successful as the specialised ones.

 

6) This then creates another evolutionary pressure, one that prevents interbreeding between these two groups. This, by the way is called speciation.

 

7) As these two groups (species) can no longer interbreed, and they live in different environments, there is now nothing that requires them to follow the same evolutionary path. Essentially they are free to adapt to their new environment better and even expand into new territories that the other species could not easily adapt to.

 

So, as you can see form this, a spread out population can, because of the differences in the environment across their range cause the species to split into two distinct groups, with one follow one evolutionary history and the other following a different one.

 

In the case of Humans and Apes, some time in the past, the population of the common ancestor was spread out over a large enough range that different groups encountered different environmental and evolutionary pressures. This resulted in specialisation adaptation in the groups and interbreeding between groups would result in a less specialised offspring that could not compete as well as the more specialised individuals.

 

These less competitive offspring became extinct, and there was evolutionary pressure (producing offspring is a costly endeavour, especially in primates as the offspring tends to ahve a longer time of reliance on the parents than most other animals) to avoid interbreeding between the groups.

 

One group became the apes we see today and because the evolutionary pressures we experienced was different from those groups, we developed in a different way (became Humans).

 

In my analogy, the "Surname" was the environmental pressures that caused the other group to experience different evolutionary pressures. In that respect, there are millions of "Surnames" (environments) and new ones are being created all the time.

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It was an analogy, not a model. Your argument is actually a Strawman (http://en.wikipedia.org/wiki/Straw_man).

 

Yes, the analogy is not perfect (if it was it would be a model). Yes, in the real world there would not have been another "surname" so to speak, but if you look at what I said as an analogy, then the other "Surname" is just the group of individuals that are starting to separate from the individual with "your surname". In that respect, my analogy holds.

 

As my answer was framed for someone who was looking for understanding of how it could occur, rather than trying to push "Evolution can not occur and I will twist any analogy to prove the model can't work", then I obviously completely misunderstood your motives for positing. This was why my answer was not a refutation of a position.

 

I was not arguing a point, I was explaining.

hey there's no need to get angry, look at what they did to my trunk and branch example, they went about telling me how they're not a trunk and branch but rather two branches, when my point was that they should grow to about the same length, i took it as a misunderstanding, but even if it's not, even if it is a straw man, what else can i do but re-explain what i meant?

 

also, i really don't see a difference between an arguing tone and a learning one, if you expected me to just nod my head to whatever you tell me and take it for granted without looking for answers your answers didn't answer or even created, then it seems i might not suit you as a student, otherwise i appreciate your posts..

 

and btw, you should be arguing too, with your "explaining" attitude it's like you're above learning yourself, it's like you're in a "sending" mode with your "receiving" ports closed, say what you have, but follow up if it shows to be bested by other participants in the argument (i'm not referring to myself of course:D)

 

So as a counter argument to your point (evolution means that one species can't separate into two or more species):

 

 

 

as for "my" argument, that's not it, mine was of the branches, why would one keep evolving and the other stop? why would one develop systems and other stay one-celled? sysiphus said different evolution rates, that's something new for me which seems to solve my "argument", although i need to look more into it..

but i can completely imagine speciation, the general idea at least, but there's some bits which were hard to swallow here:

 

1) Groups of animals of a species do not have an identical genetic code. There exist differences even within a population of animals.

:embarass:

doesn't this make your argument circular?

 

2) If this population is spread out over a large area, then the environment will be different across the range of this species.

 

3) Because there exist differences within the environments that this species ranges, it means that there will be different evolutionary pressures on the different parts of this species.

 

4) Because of this, the population of animals will start to become more and more differentiated in their genetic code.

5) Eventually, because each group within the species is becoming more specialised, then cross breeding between the groups will produce less specialised individuals and these will not be as successful as the specialised ones.

uh, i disagree, i think the off spring of the interbreeding process would be more apt to survive, BOTH environments, isn't that what we do between horses and donkeys and different types of corn?(i forgot the name).

why would such occurrence be regarded differently when done naturally?


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hey i've been thinking about this for some time:

i think the off spring of the interbreeding process would be more apt to survive, BOTH environments, isn't that what we do between horses and donkeys and different types of corn?(i forgot the name).

why would such occurrence be regarded differently when done naturally?

and when you mentioned breeding and surnames:

In my analogy, the "Surname" was the environmental pressures that caused the other group to experience different evolutionary pressures. In that respect, there are millions of "Surnames" (environments) and new ones are being created all the time.

 

i thought; won't humans, billions and billions of years from now, look a lot much similar? a son(one person), is a combination of his parents(two people).. he won't have double the capacity to have exactly both their traits, so some would be lost, so more breeding, more traits lost..

 

meaning that breeding diminishes differences, not create new ones..it starts with many but end up with less, i mean some of our grandchildren would marry others of our grandchildren, carrying shared traits and producing even more shared and common ones, till what? all of us carry the same faces?:confused:

 

or is breeding like mixing colors*?:confused:

*but won't the destination be one albeit multiple possible routs?


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What does that even mean?

more complex, unless you think you're as complex as a monkey:eek::P

 

Don't take the "tree" analogy too literally. Evolution makes no distinction between the "trunk" and the branches. Instead of a tree, think of a bunch of forking paths, neither fork being the "main" path. Each path continues to evolve, at a rate determined by its environment.

i know there's no distinction, but why would different environments deploy different rates of evolution upon the species? there's room for evolution in any environment as any other, no?

We may have evolved further from apes than apes have evolved away from each other. However, in the context of evolution no species is considered "advanced", as evolution does not imply a direction.

well i meant we have advanced from our common ancastor more than monkey have..

 

but in "advanced", can't that be "more apt to survive"?

 

 

 

I want to know what non-humans have been discussing evolution :confused:

:D that was a reply to this

not some drive towards a human notion of "more evolved" (which, interestingly, looks an awful lot like a human!).

 

Perhaps "more evolved" in the sense of having accumulated more changes since the fork than the other side of the fork. Certainly not "more advanced". I would expect that when a species forks, with one fork remaining in the prior environment and the other fork spreading into a new/different environment, one would expect the latter fork to "evolve more" in the sense that its different environment would lead to more opportunities for successful mutations.

lol, you got the first part right, but doesn't the fork which stayed in their prior environment having a smaller evolution rate than the ones which went to a new environment imply that the first ones which stayed are slowing down because they've neared their "destination"?

 

so i guess here the dilemma manifests:

 

A-creatures alive today are of different levels of complexity(hydra, the something crabs, animals, humans)

 

B-evolution rate is the same,(which is impossible and doesn't make sense, implying either species didn't start off at the same point or some have stopped at some point..bringing us to:..)

 

C-evolution happens at different rates.

and this seems a fitting answer, but on what basis? change of environment? how does that affect the rate?

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more complex, unless you think you're as complex as a monkey:eek::P

 

 

Define "more complex", because as I see it, the monkeys are more complex! They have all the parts we do AND:thicker fur, a usable tail(how awesome is that?), and an extra chromosome! Sounds more complex to me.

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A few things:

 

1) Complexity is not as easy to define as it might seem. Plants tend to be more complex than animals, for example. And an amoeba has 200 times the genetic information as a human.

2) Per #1, humans are not the most complex organisms, by most standards.

3) Complexity, however defined, is not always an advantage. See #2!

4) Per #3, "more evolution" does not mean more complexity. Microbes reproduce millions of times faster than humans, and so have had far more generations in which to evolve. There are still microbes because, evolutionarily speaking, a microbe is a highly advantageous thing to be.

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i know there's no distinction, but why would different environments deploy different rates of evolution upon the species? there's room for evolution in any environment as any other, no?

 

well i meant we have advanced from our common ancastor more than monkey have..

 

If you are already well-suited to the environment, it is not likely that any mutation will further improve your fitness. However, if your environment has recently changed substantially, or you have moved into a very different environment, you have much more room for improvement. It is still unlikely that any given mutation will improve your fitness, but it is more likely (and therefore more frequent) that one will.

 

but in "advanced", can't that be "more apt to survive"?

 

No, not really. At least, not on an individual scale. For example, mayflies are pretty successful, despite an adult lifespan of about a day. In evolution, we are only looking for that which maximizes reproduction and the survival of children to reproductive age.

 

The ability of humans to make discussion fora does not necessarily make us more "complex" or "advanced", in the context of evolution, than apes. Although chimps are probably not well-suited to finding a mate through match.com, I suspect most of us would have extreme difficulties raising children in the jungle if dumped there naked, and environment in which chimps excel.

 

lol, you got the first part right, but doesn't the fork which stayed in their prior environment having a smaller evolution rate than the ones which went to a new environment imply that the first ones which stayed are slowing down because they've neared their "destination"?

 

Nope. What destination? They may be nearing "optimal fitness" for their current environment, but this is not a destination. The environment is subject to change, particularly when you consider that the environment includes the behavior of other critters, and what is optimal today may be radically suboptimal tomorrow.

 

so i guess here the dilemma manifests:

 

A-creatures alive today are of different levels of complexity (hydra, the something crabs, animals, humans)

 

B-evolution rate is the same,(which is impossible and doesn't make sense, implying either species didn't start off at the same point or some have stopped at some point..bringing us to:..)

 

C-evolution happens at different rates.

and this seems a fitting answer, but on what basis? change of environment? how does that affect the rate?

 

There is a dilemma only if you gloss over the details.

 

First, consider that different organisms will have different rates of mutation, depending on the accuracy of their DNA polymerases and the mutagenic effects of their natural environments.

 

Second, the emergence of a phenotypic change will in part depend on how well adapted the organism already is with respect to its current environment. As noted above, this fitness is a moving target, and the farther you are from being well-adapted, the more often a mutation will confer a benefit, leading to a change in phenotype.

 

Third, consider that the emergence of new phenotypes and their spread throughout a population will also depend on your lifespan (or time to reproductive maturity), and how many offspring you produce.

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why would one keep evolving and the other stop? why would one develop systems and other stay one-celled?

If you read my posts again you can see why (i did answer that in the first post).

 

The reason is that both "branches" don't stop evolving. However, one branch might not experience a large change in their environment and so not have a large pressure to develop very different adaptations than the common ancestor.

 

In simple terms, it appears to stop evolving and you get what are commonly referred to as "living Fossils".

 

Not all species end up with living fossils because when all the groups experience different environmental changes then all the groups need to adapt to these new environments and the original features of the common ancestor can be lost.

 

 

So for the "one cell" problem. Single celled organisms are highly successful, the far out number multicellular life forms in biomass (weight for weight). However, in the environment of single celled creatures, there is some pressures to go multicellular (to avoid predation by other single celled organisms for one). However, this is not the only solution, so not all single celled organisms will evolve this trait.

 

doesn't this make your argument circular?

No. The first sentence is the evidence, the second sentence is the conclusion from that evidence.

 

The first sentence: "Groups of animals of a species do not have an identical genetic code." means that different Animals DNA has been observed to be different.

 

The second sentence: "There exist differences even within a population of animals." is the result based on the evidence presented in the first sentence and the knowledge that DNA controls the development of an organism.

 

In any argument you first present you "premises" (that the DNA of organisms are different) and then reach a conclusion based on those premises. That is all I did.

 

agree, i think the off spring of the interbreeding process would be more apt to survive, BOTH environments, isn't that what we do between horses and donkeys and different types of corn?(i forgot the name).

Yes, in many cases this is true, however the offspring of the Hybrids is often sterile and so can not produce offspring of their own. However, in some cases, especially if the species have not yet developed too much specialisations, the resultant offspring can be more vigorous than either parent, but this only really occurs when specialisation has not yet occurred and if you look at what I posted I said that specialisation had to have occurred.

 

 

However, you also said this:

i thought; won't humans, billions and billions of years from now, look a lot much similar? a son(one person), is a combination of his parents(two people).. he won't have double the capacity to have exactly both their traits, so some would be lost, so more breeding, more traits lost..

So in one place you are saying that the traits will be conserved, and the other you are saying they are lost. :confused:

 

Genetic traits are not like mixing water an milk. You don't just get a more dilute solution. This was one of Darwin's problems, at the time it was thought that the genetic traits were like a fluid and that these fluids mixed with half from the mother and half from the father it would dilute the fluid. So he could not easily see how traits could evolve.

 

There was a guy called Gregor Mendel. He discovered that traits were not like a fluid, but were discrete packets (genes). Since these packets could be conserved against dilution, it means that the traits can be retained through generations.

 

The problem is that certain "packets" rely on the existence of other packets to be correctly produced in organisms and also that there exist two copies of connected "strings" (DNA molecules) of these "packets". Some packets only need one copy to be expressed in an organism and other require two copies (it also gets more complex as sometimes one copy allows the gene to be expressed, but if two copies exist then the gene might not be expressed or even result in a disease - Sickle Cell Anaemia is one such case).

 

So, each organism has 2 strings of packets, each packet can work with or against other packets or work on its own. This creates a lot of complexity and a lot of variation on what occurs with offspring and the traits they express. Of course, the ability to express traits within the frame work has also evolved so that when important traits are needed the DNA of the organisms will be arranged so that they are less likely to have bad matchings.

 

It is also why tow populations can easily develop the inability to successfully interbreed. If one group (or both) have changes to their DNA that require an other packet to exist (or not to exist), but the other group does not have it, then this can prevent interbreeding.

 

Because these traits are conserved as "packets" that don't get diluted, then a species does not necessarily become homogeneous (they won't necessarily look similar). However, as certain traits rely on combinations of "packets" this means that within a species there will be a lot of similarities because the set of packets are needed (BTW: these "sets of packets" can also be seen as packets in their own rights too as they can be conserved and can rely on the existence of other "sets of packets"). But, if the "sets of packets" are broken up (mutations, the other packets were on a different strand of DNA, etc) then this can prevent a successful breeding.

 

hey there's no need to get angry, look at what they did to my trunk and branch example,

Sorry if I seemed angry, but the question you were asking has been answered repeatedly in this thread and so I was a little annoyed that you were not paying attention to the effort people are going to, to answer your questions.

 

In my previous post (about the Aunty), I was trying to help you visualise the answer that had been given to you (by AzurePhoenix in post #38). You said that you were having trouble understanding it.

 

I was therefore not trying to answer the initial question, just answer the question of your ability to understand the AzurePhoenix's answer.

 

But then you turned my analogy, intended to help you understand the answer, as a refutation of AzurePhoenix's answer.

 

yes i know, but what i'm saying is that, when a branch goes off the trunk, the trunk doesn't have to disappear,nor does the branch has to be the spitting image of the trunk, what i'm saying is they should both have the almost same amount of length (evolution) from since they parted, the human branch is way much longer (more evolved) than the monkey trunk.

also again, relatively speaking.

 

See, you keep pushing this question, but the answer is that that particular question is not a valid one.

 

You are using the analogy of the trunk/branch as the model (this is what I was saying in my last post). You can not do this as it results in strawman arguments.

 

To sum up the entire set of answers:

 

1) No species is more "advanced" than others because the ancestors of an organism is not the criteria by which fitness is measured. It is the immediate environment that is of any consequence. ANd besides, organisms can become less "complex" through evolution as much as becoming more complex (viruses are so simple they can not even reproduce without help from another organism, but they could not have evolved from scratch, they were once an organism that could reproduce on its own, they just lost that trait because they no longer needed it).

 

2) The Branch/Trunk dichotomy does not exist. It is an analogy and if you push any analogy too far it breaks down. The reality is that species are changing all the time. This might not result in new forms, but internally they can change (responses to new pathogens, etc). When two groups from the same species are separated for a long time, then the way they develop can result in an inability to successfully breed, and they can be exposed to different environmental pressures or even just develop different adaptation to even the same environmental pressures.

 

This means that although they share a common ancestor, they are both not the same as that common ancestor (even if one superficially resembles it). This is why they didn't like your insistence on using the "trunk" part of the analogy as the two groups are always changing and when separated the "trunk" actually splits into two "branches" (to push the analogy, but as it is only an analogy it is not the model of what occurs).

 

3) Organisms that existed in the initial environment (and how can you even say what this is as environments are changing all the time) don't necessarily slow down their rate of evolution.

 

Actually "rate of evolution" is not really a god way of putting it. Rate of evolution would be exactly the same as saying "time between generations". As bacteria have a generation time of a few hours, it could be said then that bacteria are evolving faster than humans (which have a generation time of approximately 25 years).

 

"Rate of Mutation" is probably what you are trying to say, but even then, this would not really apply either. Mutation rate is pretty constant for any species and across species, but there is variation. But Mutation rate doesn't govern how quickly species adapts on its own.

 

There is also "Rate of Speciation" but this is also not really what you are after wither as it says nothing about how "Advanced" or "Complex" an organisms is.

 

"Advanced" is only meaningful in what context it is put in, but as there are so many ways one can put the term "Advanced" into examining evolution and organisms, just using the term becomes absolutely meaningless unless you are very specific about what context you are using it in.

 

What you are doing is looking back along an evolutionary history of an organisms, then applying a preconceived assumption that we are complex and that we came from a non complex ancestor. Therefore if our ancestors were simple, and there are organisms alive that are similar to it, then these must be "Simple" too.

 

This is a logical fallacy called "equivocation" (not between words, but between forms of animals). Any organism alive today has had the same length of time of evolutionary history as we have. Therefore, by the only metric available for that, they are equally as advanced as us. Sure, they might have a form that is superficially like our ancestors, but they only look that way because they have become so well adapted that there is nothing more they can do to be any "better".

 

How is that for advanced: They don't need to change because they are the best at what they are doing. Where as humans have changed quite a lot recently (speaking of course in terms of evolutionary time), so this must mean we are not all that well adapted for the environments we were in. One could say therefore is we are less adapted to the environment than another species, then that other species was more "advanced" than us.

 

So single celled organisms are "Better" than us because they have become so well adapted to their environment that they have not had to change significantly for billions of years. We can be said to be more advanced than single celled organisms because we have a complex system of celled that work togather.

 

Can you now understand, it depends on what Metric by which you measure "advancement". If the metric is how well adapted an organism is, then single celled organisms are far more advanced than multi celled organisms. If you are using the metric of coordination, then multi cellular organisms are more advanced.

 

No one organisms can therefore be said to be "better' over all than any other.

 

We are more advance than monkeys in terms of intellectual capacity, but monkeys are more advanced at us at climbing through trees.

 

If our environment for us changed so that climbing through tress was more important than intelligence, then we would be considered extremely poorly adapted and monkeys would be considered very well adapted.

 

But if the environment wa changed so that climbing through trees was not a good thing (say we cut them all down), then monkeys would be considered ver poorly adapted.

 

In the past, when the common ancestor of the monkeys and us was alive, the population was spread over a large enough area that it covered different environments. In one part of the environment, climbing through trees was a really good adaptation and their environment didn't change enough for that trait to be considered a bad adaptation and so was conserved through the generations and species to modern monkeys.

 

However, in another part of the range, the population was in an environment that was not good for the adaptation of climbing through trees (say on the savannah where there weren't many trees). Instead other problems existed and the group evolved to meet these issues, and one trait was intelligence.

 

Over time the common ancestor either was absorbed into one or another of these groups and so ceased to exist (although if one of the groups didn't need to change their form much for their adaptations, they could still superficially resemble them) or even evolved into a completely different group.

 

Neither of the new groups are not more advanced than the common ancestor, only that they are better adapted than the common ancestor is the the NEW environments they find themselves in.

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"Advanced" is only meaningful in what context it is put in, but as there are so many ways one can put the term "Advanced" into examining evolution and organisms, just using the term becomes absolutely meaningless unless you are very specific about what context you are using it in.

in their ability to live, to maintain their life, to stay alive.

 

i.e. the amount of sweat evolution put into them, as survival is evolution's handiwork.

 

Can you now understand, it depends on what Metric by which you measure "advancement". If the metric is how well adapted an organism is, then single celled organisms are far more advanced than multi celled organisms. If you are using the metric of coordination, then multi cellular organisms are more advanced.

IMHO, this is a fallacy, these two metrics are the same.

 

Q:

why has coordination been introduced, if not to be well adapted?

No one organisms can therefore be said to be "better' over all than any other.

 

We are more advance than monkeys in terms of intellectual capacity, but monkeys are more advanced at us at climbing through trees.

intellectual capacity is the finest form of evolution, of "adaptation", and the holder of such trait can be considered to be the most advanced and ccomplex.

 

because intelligence is able to replace any other traits missed out, that is why humans are dominating the earth, not monkeys, and it is monkeys who are in zoos, not humans, and if a meteor was going to strike the earth, humans can go into space or under water like fish and dolphins, not monkeys.

 

humans, with their intelligence, are the most able to adapt.

 

they are the most complex and advanced.

 

a black belt karate master is nothing in front of an old lady with an AK-47.

that is an analogy, for the AK-47 can be useless in other situations where karate is more useful.

intelligence is not, it is a master key, evolution's finest.

If our environment for us changed so that climbing through tress was more important than intelligence, then we would be considered extremely poorly adapted and monkeys would be considered very well adapted.

 

But if the environment wa changed so that climbing through trees was not a good thing (say we cut them all down), then monkeys would be considered ver poorly adapted.

 

In the past, when the common ancestor of the monkeys and us was alive, the population was spread over a large enough area that it covered different environments. In one part of the environment, climbing through trees was a really good adaptation and their environment didn't change enough for that trait to be considered a bad adaptation and so was conserved through the generations and species to modern monkeys.

 

However, in another part of the range, the population was in an environment that was not good for the adaptation of climbing through trees (say on the savannah where there weren't many trees). Instead other problems existed and the group evolved to meet these issues, and one trait was intelligence.

as i said, intelligence i\fits all enviornments, even those not intended for life(like space).

 

but i'm interested in hearing of the environment that made intelligence a must, instead of climbing trees.

(not to mention that for those who climbing trees is a necessity for, they only need the first 6 to 7 years of their life to develop such ability, the human brain and body is capable of feats close or similar to those of many animals. climbing trees like monkeys, running fast like four legged animals, staying underneath water for so long nearly like some underwater mammles, relatively spaeking of course.)

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Our intelligence, however, is merely the extreme form. A trait must be useful in some way at ALL levels in order to evolve. Evolution will not maintain a trait that's currently damaging just in case it becomes useful later.

 

And there is a huge cost to intelligence - it requires a LOT of calories to maintain. Human brainpower can accomplish a lot, but it cannot let us live on less than ~2000 calories a day. In an environment with severe nutrient depletion, salamanders will live happily while we all starve to death.

 

How beneficial is merely half our current intellect? A tenth? Is it beneficial enough to justify the energetic costs?

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Good point - I have asked that question too (or thought about it)...

 

What is the definition of domesticated?

 

I always thought it would be the production of testosterone hence less aggressive and leading into eventual changes in mind, body and spirit, right? I mean sounds good to me...

 

But someone then brought up to me, what about the female species? Are they so entwined with the levels of testosterone?

 

I don’t know?

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Our intelligence, however, is merely the extreme form. A trait must be useful in some way at ALL levels in order to evolve. Evolution will not maintain a trait that's currently damaging just in case it becomes useful later.

 

And there is a huge cost to intelligence - it requires a LOT of calories to maintain. Human brainpower can accomplish a lot, but it cannot let us live on less than ~2000 calories a day. In an environment with severe nutrient depletion, salamanders will live happily while we all starve to death.

 

How beneficial is merely half our current intellect? A tenth? Is it beneficial enough to justify the energetic costs?

 

but the tenth of our intellect is sufficient for us to get over fed, food is literally wasted in our world, if you mention Africa, well get into politics, but go to a restaurant or cafeteria and peek inside the "waste" bins, sit around after a wedding is finished to see where all the food goes to..my point is, even though most of us use only about tenth of our brain power, that is more than sufficient to get us enough food for us to throw in garbage bins.

 

if all four legged animals along with plants died out or burnt one day, humans can fish, but would salamanders last long enough to develop teeth to become carnivores or complex stomachs to digest seaweed?

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The whole "we only use a tenth of our brain" is a total myth. A human with 1/10th of our intellect would be about as smart as a dog.

 

You missed the point - intelligence comes in a series of intermediate levels, each of which must be useful enough in the organism's environment to justify the expense. Will a smarter beetle have more offspring? A smarter dog?

 

We're naturally biased to claim intelligence as a universal good, but the fact remains that for most species, it's not even useful.

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My two cents on the subject is as follows:

 

Environment stands alone separate from an organisms evolutionary development just like a house would grow or the neighborhood would exist indifferent to it’s citizens or occupants. And it’s just random luck of the draw who gets the long lasting survivable traits from DNA that are best suited for the “house or neighborhood”.

 

Therefore it’s just a propensity that evolution is best suited for it’s environment. When truth be told, evolution can easily evolve into species not suited for “that” environment. Right?

 

Let’s say we humans made a conscious effort to only breed people who have a birth defect of sorts - we just evolved the human race into the environment not being suited for it to survive in. Right?

 

So in closing what I’m trying to say is: yes environment and evolution do have a relationship (influence on each other) but still stand alone indifferent of each other.

 

But also keep in mind that the randomness in a birth isn’t so random that one offspring can have wings ready to fly during his life to the next. I’ve heard that there are a handful of basic DNA traits at first that end up being used in “new” ways (to create randomness). Meaning a DNA trait for moving, DNA trait for breathing, A DNA trait for reproduction. So at some level DNA is composed of, really, just a handful of basic Points that life must have to be considered life (mammal and or reptile of this here nature).

 

I find that rather interesting: that means there is a rather small threshold that were dealing with when talking about the propensity to be the right combo for that environment.

 

What does that mean? Well, mistakes are easily made and Corrected (in the sense that we are talking about millions of years that is).

 

I also think that’s what “spawned” that new game that came out a year ago about creating creatures that you yourself create and try to live on some planet (you know is it called Spawn) you know the one I’m talking about, it was all the rave? Meaning this discovery of there just being a handful of traits that are used in new ways to create randomness...

 

I just bet...

Edited by Catharsis
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My two cents on the subject is as follows:

 

Environment stands alone separate from an organisms evolutionary development just like a house would grow or the neighborhood would exist indifferent to it’s citizens or occupants. And it’s just random luck of the draw who gets the long lasting survivable traits from DNA that are best suited for the “house or neighborhood”.

 

Therefore it’s just a propensity that evolution is best suited for it’s environment. When truth be told, evolution can easily evolve into species not suited for “that” environment. Right?

Nope. The environment is the template doing the selecting. As organisms spawn phenotypes ill suited for their environment, they are "selected out".

 

Let’s say we humans made a conscious effort to only breed people who have a birth defect of sorts - we just evolved the human race into the environment not being suited for it to survive in. Right?
That would not be evolution (natural selection), it would be artificial selection - a sort of generating an environment for the intended outcome.

 

So in closing what I’m trying to say is: yes environment and evolution do have a relationship (influence on each other) but still stand alone indifferent of each other.
Environment is part and parcel to life, and therefore to evolution.
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I was told that a giraffes neck got long only because (at random) an offspring was born with a longer neck hence making it easier to reach more food therefore (in the long run) striving in the environment more productively, being more attractive to the females, hence, sharing his offspring with that propensity to have a long neck.

 

The need to have a longer neck to reach higher for leaves is not influenced by the environment. It’s just there for us organisms to survive in.

 

Living in the sun (from what I understand) does not physically effect the DNA to make the skin black (like people from Africa). Rather over the millions of years people who at random exhibited the darker pigment were more popular, more successful, more happier, so that in the long run reproduced more. No?

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I was told that a giraffes neck got long only because (at random) an offspring was born with a longer neck hence making it easier to reach more food therefore (in the long run) striving in the environment more productively, being more attractive to the females, hence, sharing his offspring with that propensity to have a long neck.

 

The need to have a longer neck to reach higher for leaves is not influenced by the environment. It’s just there for us organisms to survive in.

 

Living in the sun (from what I understand) does not physically effect the DNA to make the skin black (like people from Africa). Rather over the millions of years people who at random exhibited the darker pigment were more popular, more successful, more happier, so that in the long run reproduced more. No?

No.

 

Making it pure sexual selection would require ignoring all the species that also adapt to environment but reproduce by mitosis or other asexual/non-sexual reproduction.

 

The proto-equine ancestors of the giraffes moved into an area where trees were more common than the grasses and bushes they originally fed on. Those proto-equines who could not reach the leaves could not get enough food from the harder grasses of the area, and so either did not survive to mate, or were too weak to successfully mate. Whether or not the females of this species were allowing only the stronger males to mate with them or not, there would have still been a selection pressure for taller proto-equines, and proto-equines with longer necks.

 

Melanin (a skin pigmentation) is functional as part of the cellular mechanism that produces vitamin D. If you look at a chart of melanin predominance over the world, you will find a pretty clear connection between overall exposure to direct sunlight and the presence of melanin in the skin of long-term populations. Again, whether or not skin color was considered "attractive" or not, there is still selection pressure from the environment.

 

Sexual selection itself is just another factor in the environment in which a set of phenotypes is operating.

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I think we’re in a cycle of semantics.

 

When you say pressure from the environment, I’m saying “it’s there for us organisms to survive in”.

 

I’m just trying to point out that straining you neck isn’t going to effect your DNA.

 

I know on some level, such as fish for example, will be more sensitive to it’s immediate chemical environment and will evolve accordingly.

 

But for mammals I don’t think they work like that - like they say dinosaurs grew so big because of the amount of excess oxygen in the air. I don’t think because of that extra o2 it chemically altered the DNA.

 

Is what I’m trying to point out.

 

But there has to be a gray area since we did evolve from fish and I’m sure we all can agree that fish were and are susceptible to their chemical environment...

 

So I guess were back to where we started again - this raises an interesting issue, no?

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I think we’re in a cycle of semantics.

 

When you say pressure from the environment, I’m saying “it’s there for us organisms to survive in”.

 

I’m just trying to point out that straining you neck isn’t going to effect your DNA.

And no one said it would.

 

I know on some level, such as fish for example, will be more sensitive to it’s immediate chemical environment and will evolve accordingly.

 

But for mammals I don’t think they work like that - like they say dinosaurs grew so big because of the amount of excess oxygen in the air. I don’t think because of that extra o2 it chemically altered the DNA.

 

Is what I’m trying to point out.

 

But there has to be a gray area since we did evolve from fish and I’m sure we all can agree that fish were and are susceptible to their chemical environment...

 

So I guess were back to where we started again - this raises an interesting issue, no?

Not really. From where I stand, you appear not to know what evolution is.

 

Here's a nice little primer:

 

http://www.youtube.com/watch?v=vss1VKN2rf8

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Yea, but regardless of what you think I know or don’t know I’m still entitled to make a statement.

 

Yes or no, right?

 

As far as everything else well, I guess it all speaks for itself - such skills in encouragement and inspiration... This forum will be teaming with enthusiastic participants...

 

Like I’m going to spend time in a debate over semantics; forums someday in the future will start to censure it’s members, just wait and see.

 

Oh I just didn’t make it personal - I’ve got lots of friends and am highly regarded on my science forum come join us we have lot’s of members participating in all sorts of interesting discussions, it’s the wave of the future.

 

See ya...

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