Denial of evolution IV

[Trippy]

bad example since an extra thumb is cleraly a mutant on an existing blueprint, wheras the girrafes nerve is not a mutant but is the main blueprint.
Oh, and again you or horrifically trivaializing the task you have set the mechanisms, ie, that nerve was "for the ride", ie, it "coevolved " along with the neck. So you beleive that the nerve got the right mutations to keep up with the rest of the neck "on time"?
this is what i call invoking a miracle

This is bogus, and all you need to do to realize this is think about your own body - specifically, think about your spinal column.

The mistake you've made is in assuming that the length of the spinal column and the length of the nerve are independent.

Are you as tall as you were when you were 10 years old?

No, probably not.

What's my point? Occasionally in Statistics, we get these things called 'hidden variables' - it's where you get a correlation between two unconnected things - like chocolate consumption and road death tolls, but the correlation only occurs because of some other third variable - in this case population growth.

In the case of the spinal colum, the only thing implied is that the size of the Vertebrae and the length of the nerve are controled by the same factor - in this case, as I understand it, the length of both are controlled by the same genes, and the growth of both is controled by the expression of the same proteins and enzymes, but there are (obviously) differences between the cells that become the bone, and the cells that become the nerve.

So because the growth of both are linked to the same factors, you can not change one without changing the other, because both are controled by the same third thing.

While this might seem like proof of an intelligent designer, by incorporating a 'fail safe' also consider that it is the 'simplest' way of arranging things. And while you might wonder why evolution would favour this over an alternative approach, stop and consider the implications of any alternative.

There are two options available to us - dependant devlopment, or independant development of the vertebrae and nerves. I am suggesting that the information we have available shows that the development of both is dependant on some third factor (the Hox Genes), with the net result being the illusion of co-evolution, and this being the simplest way of doing things.
The alternative is they are controled by independantly.
Consider the implications of that.
How long is a Giraffe with a spinal cord that's too short for its neck going to survive. The answer is, it probably isn't. It's probably going to die at an early age, due to the spinal cord being severed, or pulling the brain down into the spinal colum.
How long is a Giraffe with a spinal cord that's too long for its neck going to survive for? Again, it probably isn't going to survive to sexual maturity, and it's probably going to die of some complication resulting from having your spinal cord exposed.

Similar arguments, incidentally, can be made for the heart size, and blood pressure 'issues' as well.

Giraffe bloodpressure (presumably) follows a normal distribution about some mean value (same for heart size).

As neck length increases over time, those Giraffes that might ordinarly have been hypertensive, are going to find themselves being more successful with greater frequency than those with 'mean' blood pressure, and those giraffes with long necks, that would ordinarily have been hypotensive are probably going to be the least succesfull, and are probably going to find themselves prey pretty quickly.

So we end up with a regime where

Long Neck, Low blood pressure < Average Neck, Average Blood pressure < Long neck, Average blood pressure < Long neck, high blood pressure.

The net effect being that evolutionary pressures, combined with physiological requirements are going to select for those Girrafes with long necks and high blood pressure.

And please, you'll note that I only made two initial assumptions:
1. That Giraffe blood pressure exists accross a range of values.
2. That Giraffe neck length has increased.
And from those two assumptions, we have effectively explained the co-evolution of girraffe blood pressure, and Girraffe neck length.
Girraffes with neck lengths above the population mean, and blood pressure below the population mean probably weren't even able to stand up, and so probably became prey quickly.
Giraffes with neck lengths and blood pressures around the population means, were as successful as every other giraffe.
Giraffes with neck lengths around the population mean, but blood pressures above it, were no more or less successfull than the rest of the population.
Giraffes with neck lengths above the population mean, but blood pressures around the population mean were slightly more successful, because they could reach more food, but may have had the occasional bought of giddyness.
Giraffes with neck lengths and blood pressures above the population mean were the most successful, because they reach more food, and did not have the bouts of light headedness to deal with - this may even have given them an advantage over those from the previous groups, because they would be able to keep their necks erect more.

No Magic, no mystery, just a trait that was already in the population giving a slight advantage.

 

[Zenithar66]

I'm not incredulous, I do understand it. The giraffe received tremendous benefits from a long neck, and a nerve that used to be short had to become longer because there is no evolutionary mechanism that would radically rethink the routing.

You are living in a dreamworld man, if you truly believe that the nerve HAD to keep up then you need to go back to the drawing board on evolution, and here i am being told i know nothing...wow
Simply stating it HAD to also simply masks the fact that you are invoking a miracle that cannot be demonstrated.

The nerve does have a function, but it's tremendous length does not. There can be no benefit from a longer nerve, since it's function is to transmit sensory information and obviously a longer one wouldn't be as fast.

And indeed maybe there needs to be a reason for this lag in the impulse. Then again this all assumes it is wired wrongly which is simply that, an assumption,

There are too many examples of this to dismiss as a misunderstanding of it's true function. For example, a whale's vestigial hind leg bones may have a purpose, but they are quite obviously a remnant of an animal that used to use them to walk.

simply stating its "obviously a remnent" of an animal that used to walk proves nothing. doesnt it have a use in birth?(i have no problem if whales somehow evolving from land mammals im simply not conviced yet, nor do I think for a moment that the proposed mechanisms are up to the task).
and simply stating that whales came from land mammals says nothing abotu the mechanisms, it simply pre supposes them irrationally.


my point stands, simply not knowing the function does not mean you can draw such conclusions and its poorly desinged, that is quite flawed logic.

It had to. Any giraffe who's nerves didn't keep up with it's neck would die. They might even be part of the same gene. Any giraffe who's neck didn't evolve would also die.

again wtih the "it had to"..wow, if this is the logic used to support coevolution then Im worried. Someone else(i think it was a moderator!) used the very fact that girrafes are here as evidence! I hope no one else on this forum think it "had to"..did you consider how much other things would "have to " co evolve also? again, its invokign a miracle and a rather unbelievable one at that..




It works, but it's not optimal. A designer can start from scratch. So say there is a designer that could not change the design is inherently contradictory.


No dude, you don't get to postulate a designer for life and say it isn't the god of religion. You are trying to remove the religion from Intelligent Design, which is the reason for the term replacing "creationism" in the first place.[/QUOTE]

 

[spidergoat]

You are living in a dreamworld man, if you truly believe that the nerve HAD to keep up then you need to go back to the drawing board on evolution, and here i am being told i know nothing...wow
Simply stating it HAD to also simply masks the fact that you are invoking a miracle that cannot be demonstrated.

I'm not invoking a miracle, I'm invoking evolution by natural selection. Perhaps my phrasing is problematic. What happened was that a variety of giraffes existed. The ones with longer necks survived or bred more and became more common, and thus all subsequent variations had longer necks until the species achieved some balance between the height of trees and the cost of having a long neck. Obviously, if at any point the giraffe was born with a nerve shorter than it's neck, it would also tend to die. But I think that didn't happen because the regulation of nerve length and neck are probably part of the same mechanism.

And indeed maybe there needs to be a reason for this lag in the impulse. Then again this all assumes it is wired wrongly which is simply that, an assumption,

Quite a good assumption actually, based on science.

simply stating its "obviously a remnent" of an animal that used to walk proves nothing. doesnt it have a use in birth?(i have no problem if whales somehow evolving from land mammals im simply not conviced yet, nor do I think for a moment that the proposed mechanisms are up to the task).
and simply stating that whales came from land mammals says nothing abotu the mechanisms, it simply pre supposes them irrationally.

That's what is called an argument from incredulity. You are simply stating that you cannot believe evolution from natural selection is capable of leading to the diversity of life, without having an argument against it.

my point stands, simply not knowing the function does not mean you can draw such conclusions and its poorly desinged, that is quite flawed logic.

The function is clear. We are talking about an unnecessary loop that has to go all around a location that it isn't even connected with! The only logical explanation is that once the neck was short and it didn't matter. Now the neck is long and it's problematic, but not so much that it kills the animal.

again wtih the "it had to"..wow, if this is the logic used to support coevolution then Im worried. Someone else(i think it was a moderator!) used the very fact that girrafes are here as evidence! I hope no one else on this forum think it "had to"..did you consider how much other things would "have to " co evolve also? again, its invokign a miracle and a rather unbelievable one at that..

There is no miracle invoked here whatsoever. Things "have to" evolve only because if and when they don't, the creature or plant does not live. Or doesn't live as well.

 

[Hercules Rockefeller]

Mod note:

im sorry but what the hell is this? I am actually in shock .... care to answer this one oh holy moderator?

Well, I was about to. I was in the process of writing a lengthy explanation with substantiating references to your posts. But then I saw that you’ve brought up the giraffe’s neck rolleyes and I immediately stopped and deleted my writing as I am now convinced my initial assessment was accurate.

The evolution of the giraffe’s neck is a classic so-called “evolutionary problem” that is proffered by creationists. Of course, it is possible to ask valid scientific questions regarding the evolution of giraffes, and I would be all for that. But you went ahead and offered this drivel:

...can you prove (as is claimed by a recent paper i read on the evolution of teh girrafes neck) that both the neck AND the higher blood pressure AND the heart co evolved by the mechanisms you invoke? or can you simply belive based on shoddy evidence of point mutations in bacteria...

Shoddy evidence? You clearly know nothing about metazoan or protozoan biology and evolution. To explain away conclusions regarding the evolution of giraffe as being based on “shoddy evidence of point mutations in bacteria” reveals a gross lack of understanding and knowledge of the subject matter you are embarrassingly attempting to repudiate. You do not understand how the scientific method works nor do you understand how a scientific theory is developed. This is amply demonstrated by your continual insistence that people provide ‘proof’ for this and that. You need to complete your high school biology classes first before you can start questioning qualified scientists and their peer-reviewed published work.

It is now quite clear to me that you’re taking your cues from creationist sources. And this thread is where that sort of wilfully ignorant nonsense gets quarantined.

This is exactly what happened on that website askabiologist.com becuase i was "denying" evolution(actually I got banned).

Hmmm, can’t say I’m all that surprised. Perhaps I should mention that the situation for creationists here rarely ends well either. Bannings are a typical end point. This is because part-and-parcel of creationism is intellectual dishonesty. You cannot have the former without practicing the latter. And we really don’t like intellectual dishonesty. It is anathema to science.

 

[Zenithar66]

I'm not invoking a miracle, I'm invoking evolution by natural selection. Perhaps my phrasing is problematic. What happened was that a variety of giraffes existed. The ones with longer necks survived or bred more and became more common, and thus all subsequent variations had longer necks until the species achieved some balance between the height of trees and the cost of having a long neck. Obviously, if at any point the giraffe was born with a nerve shorter than it's neck, it would also tend to die. But I think that didn't happen because the regulation of nerve length and neck are probably part of the same mechanism.

you mean thats what you assume happened. I personally dont know what happened, what i can say is, the girrafe clearly evolved.
"But I think that didn't happen because the regulation of nerve length and neck are probably part of the same mechanism"

and what about veins, muscle, heart etc, all that is clearly regulated by differing genes? so you are invoking a miracle IMO to say they coevolved. cant u even see the astronomical odds of that actualy happening. I think thta somethings can be, while statiscally possible, soo improbable that they will never actually happen. Again i cant prove it didnt happen, but as of yet i am not willing to commit to such a large leap.

Quite a good assumption actually, based on science.

Indeed it is based on science, but it is still an assumption and it dilly dallyes around the fact that the nerve would have to had coevolved with the neck and everthing else,

That's what is called an argument from incredulity. You are simply stating that you cannot believe evolution from natural selection is capable of leading to the diversity of life, without having an argument against it.

Actually i didnt say it cannot(as far as i recall?) only that i dont see enough evidence to leap to such conclusions as it created ALL the diversity of life..evidence FOR a theory is not prooving it factual(the mechanissm, not the fact that evolution occurs)

The function is clear. We are talking about an unnecessary loop that has to go all around a location that it isn't even connected with! The only logical explanation is that once the neck was short and it didn't matter. Now the neck is long and it's problematic, but not so much that it kills the animal.

again you assume it is unnecesary, I will not do that as i know in my expreince of nature that many times it may appear something is useless or out of place but then it turns out there was a use for it.
theres no real need to assume its not like that for a reason..
I mean, you clearly believe the heart coevovled with the neck right.

There is no miracle invoked here whatsoever. Things "have to" evolve only because if and when they don't, the creature or plant does not live. Or doesn't live as well.

and of course why then didnt the girrafe die? rather then experince a miracoulous event such as coevolution? indeed, even if it turns out that everthign about the mechanisms are indeed true and my fears are layed to rest, them we certainly are the product of an even greater miracle then if the theists god had pulled us straight from dirt!
life is miraculous whichever "side" your on, unless you've lost that sense of wonder from daily doses of tv and chemical in your water of course.

 

[Zenithar66]

Well, I was about to. I was in the process of writing a lengthy explanation with substantiating references to your posts. But then I saw that you’ve brought up the giraffe’s neck rolleyes and I immediately stopped and deleted my writing as I am now convinced my initial assessment was accurate.

you stopped typing up simply becuase i brought up an argument that you didnt like the sound of? intersting logic and again you assume i am a creationist which is getting quite boring. how about instead of making sill assumptions actaully giving me your view of the supposed coevolution of girrafes neck, intersetingly ive never heard a creationist talk about this, they simply look at the amazing reite mandible and blood system and say, god did it, wheres i say, i am not yet convinced by any means that the proposed mechanisms did, so how bout it, whats your view of its evolution,

The evolution of the giraffe’s neck is a classic so-called “evolutionary problem” that is proffered by creationists. Of course, it is possible to ask valid scientific questions regarding the evolution of giraffes, and I would be all for that. But you went ahead and offered this drivel:


Shoddy evidence? You clearly know nothing about metazoan or protozoan biology and evolution. To explain away conclusions regarding the evolution of giraffe as being based on “shoddy evidence of point mutations in bacteria” reveals a gross lack of understanding and knowledge of the subject matter you are embarrassingly attempting to repudiate.

Ok, i admit, im no expert on metazoan or protozoan biology and evolution,(care to reccomend any papers?) and yet I am not saying i am, but simply addressing a certian animal. Ineed i do beleive , with my limited knowledge that the evidence that such components co evolved is shoddy and based on MUCH extrapolation to the poitn of invoking a miraculus event. many people indeed do refer me to point mutations and deletions in bacteria when i bring up an animals evoltuion, which is odd. I dont know whats with this "embarrassingly " stuff, if i made a mistake then hey, thats life, part of the reason i came here was to be rebutted on my opinions, but i did excpect a tad more maturity tbh,

You do not understand how the scientific method works nor do you understand how a scientific theory is developed. This is amply demonstrated by your continual insistence that people provide ‘proof’ for this and that. You need to complete your high school biology classes first before you can start questioning qualified scientists and their peer-reviewed published work.

I have not continually asked for proof at all, i may have asked a few times but i have also been asked for proof, that just how it goes and your simply cherry picking instead of addresing anything I've said with your views. Indeed one does not have to complete any biology classes to queston anything, one needs only to educate one self with appropriate sources. Do you have some kind of authority complex?
Indeed i do know how the scientific method works, what does this have to do with my questions of the girrafe?
Unless you havent done the reserach you'll realise that these guys are only human and many incedences of fraud do and have occured, like anythign esle, just read the information and take from it your OWN conclusions..synthesise and decide.

It is now quite clear to me that you’re taking your cues from creationist sources. And this thread is where that sort of wilfully ignorant nonsense gets quarantined.

What exactly am i being willfully ignorant about, i have been fed pure religion on the part of the girrafes evolution so far.
Oh, and i am not taking my cues from creationist sources so please stop wtih this ridiculous accusation its making you look like you simply dont want to answer anything. I was reading a paper on scholar about the girrafe and accacia leaves when i thougth, hmm, the girrafes neck is amazing structure, wonder what the conventianal explanation is? then found myself utterly uconvinced by it. The only drivel here is your childish insistence that you have somehow "rooted out" another creatonist.

again, what is your own views on the girrafe?




Hmmm, can’t say I’m all that surprised. Perhaps I should mention that the situation for creationists here rarely ends well either. Bannings are a typical end point. This is because part-and-parcel of creationism is intellectual dishonesty. You cannot have the former without practicing the latter. And we really don’t like intellectual dishonesty. It is anathema to science.

 

[Walter L. Wagner]

we certainly are the product of an even greater miracle then if the theists god had pulled us straight from dirt!
life is miraculous whichever "side" your on, unless you've lost that sense of wonder from daily doses of tv and chemical in your water of course.

I believe if you keep that perspective, you will see that that is what motivates biologists to research the evolution of life. As you admit, evolution occurs, and scientists simply look to fill in the gaps of knowledge we currently have, using our knowledge of evolutionary theory.

I note that most examples most people post for evolution are about animals. I prefer plants, as it is more involved in many ways, and gives a deeper understanding.

You should read about the earliest land-plants, which descendants are the mosses and liverworts currently extant. They are haploid in form for most of their life, but produce a diploid 'fruiting body' that then undergoes meiosis and release haploid spores. 'Higher' land plants have the diploid phase as vascularized tissue, but still retain the haploid phase, as a separate organism, as part of their life-cycle. There is a clear transition in form through to the most recently emerged forms, the flowering plants, which have the most greatly reduced haploid phase of all. This evolution in form is factual and can be seen under the microscope. The biochemical mechanisms are still being elucidated. But we do not posit a Genie made change upon change over time, but rather natural selection. But it is still amazing/miraculous that the laws of physics/chemistry/biology/geology/astronomy all work towards evolution of humans who can appreciate beauty and ponder their origins.

 

[Zenithar66]

I believe if you keep that perspective, you will see that that is what motivates biologists to research the evolution of life. As you admit, evolution occurs, and scientists simply look to fill in the gaps of knowledge we currently using our knowledge of evolutionary theory.

i think though that its about more then "filling in the gaps", i think we should reevaluate the mechanissm invoked when we look at adaptions.

I note that most examples most people post for evolution are about animals. I prefer plants, as it is more involved in many ways, and gives a deeper understanding.

I know what you mean, i am utterly fascinated by plants and am curretnly reading introductory plant biology as we speak, i read introduction to botany recently, mind blowing book!
growth, circaden rythms, specialised roots,symbiosis are some things that simply fascinate me. not to mention the stunning process of abscission which is just..wow!
I think that the most amazign adaptions in nature are to be found in plants,!

dam, i cant remember waht it was called but i recetnly found a desert plant that literally screws itself into the ground! another that has literally windows on its modified tubular leaves to allow light into the below ground chloroplast bearing leavees.

Plants are one of the main reasons im questioning the theories mechanisms beucause it seesm that the only explanations are not actual evaluations but rather, well, simply applying the mechanisms on it or using words such as coevolution or pressures to explain for instance the midn twistingly amazing orchids!! hammer orchid is just unreal.
Also the carrion lilies to hit on both the smell of rotting mean, to look like it, and to produce hairs to look like a dead featus, i honestly cant yet simply ascribe such bliind mechanisms to these genius plants, not yet anyhow.

You should read about the earliest land-plants, which descendants are the mosses and liverworts currently extant. They are haploid in form for most of their life, but produce a diploid 'fruiting body' that then undergoes meiosis and release haploid spores. 'Higher' land plants have the diploid phase as vascularized tissue, but still retain the haploid phase, as a separate organism, as part of their life-cycle. There is a clear transition in form through to the most recently emerged forms, the flowering plants, which have the most greatly reduced haploid phase of all. This evolution in form is factual and can be seen under the microscope. The biochemical mechanisms are still being elucidated. But we do not posit a Genie made change upon change over time, but rather natural selection. But it is still amazing/miraculous that the laws of physics/chemistry/biology/geology/astronomy all work towards evolution of humans who can appreciate beauty and ponder their origins.

Indeed i have much reading to do. From what i have read the whole episode of plants coming onto land seems to me like pure specualtion.
Im sure when i delve deeper into the evolution of plants it wont be so simple as the explanation you've give.
but again, i am no expert but certainly hope to be since i am totally enamoured by the plants of the world, the are the sorce of almost everthing we use!

 

[iceaura]

I think intelligent design is indeed a theory apart form religion, that is not to say most religous people arent using it to push creationist agends, i merely mean that design is quite apart from religion and whether or not we can detect it in nature is apart from any particular god.

As long as you dismiss evidence of lack of intelligence in design, trying to claim that all apparent design problems are somehow mysteriously purposeful in ways beyond our understanding, you are not employing a theory: you are evangelizing belief in an entity beyond reason or contradiction - a deity.

Scientific theory can be falsified, contradicted by evidence and reason. That's probably (cf Karl Hopper) its basic characteristic.

 

[spidergoat]

you mean thats what you assume happened. I personally dont know what happened, what i can say is, the girrafe clearly evolved.
"But I think that didn't happen because the regulation of nerve length and neck are probably part of the same mechanism"

and what about veins, muscle, heart etc, all that is clearly regulated by differing genes? so you are invoking a miracle IMO to say they coevolved. cant u even see the astronomical odds of that actualy happening. I think thta somethings can be, while statiscally possible, soo improbable that they will never actually happen. Again i cant prove it didnt happen, but as of yet i am not willing to commit to such a large leap.



Indeed it is based on science, but it is still an assumption and it dilly dallyes around the fact that the nerve would have to had coevolved with the neck and everthing else,....

You are laboring under a misconception. Evolution does not work like this. It's not that when a species changes, every individual part of the species has to mutate separately. That's absurd. We simply had giraffes with shorter necks, and giraffes with slightly longer necks, just like you can see people that are shorter or taller. DNA does not contain a blueprint for every individual organ, it's precise size, irrespective of the other parts. Some parameters are guided by overall growing guidelines while the creature is still an embryo.

Please do some further research on the topic before you pretend to know what you are talking about.

 

[origin]

again wtih the "it had to"..wow, if this is the logic used to support coevolution then Im worried. Someone else(i think it was a moderator!) used the very fact that girrafes are here as evidence! I hope no one else on this forum think it "had to"..did you consider how much other things would "have to " co evolve also? again, its invokign a miracle and a rather unbelievable one at that..

You keep discussing 'coevolution' [coevolution is a real term but NOT as you are defining it] as if this is a real term. Your use of the term 'coevolution' is essentially a made up definition that adds a false complexity to the situation to make it seem implausible. Trippy had a very good post about giraffe evolution and why there is no 'coevolution' just good old fasion regular evolution.

Here is a very simplistic explanation. There is a population of proto-giraffes. Like all populations there is a range of heights and sizes. During drought conditions food becomes scarce and the animals with the longer necks could reach the leaves higher in the trees and they survived to pass on their genes.
There is no 'coevolution' needed. The heart and nerves did not evolve indepedently. The larger animals simply had larger hearts and longer nerves due to there size, kind of obvious. Large animals with long necks and small hearts equal lion food. The large animals with long necks and strong hearts equal breeding animals - simple.

Evolution works on populations that are already here this is why giraffes have the same number of neck vertibrae that other mammals do. If a designer was in charge it would make much more sense to toss in a few more vertibrae. Nature does not have that luxury.

 

[Zenithar66]

The mistake you've made is in assuming that the length of the spinal column and the length of the nerve are independent.

first off can you provide me with evidence that any mutation taht makes the spinal column longer also make the nerve because that certainly would be intersting!

In the case of the spinal colum, the only thing implied is that the size of the Vertebrae and the length of the nerve are controled by the same factor - in this case, as I understand it, the length of both are controlled by the same genes, and the growth of both is controled by the expression of the same proteins and enzymes, but there are (obviously) differences between the cells that become the bone, and the cells that become the nerve.

So because the growth of both are linked to the same factors, you can not change one without changing the other, because both are controled by the same third thing.

indeed, even if this was true, is the heart also controlled by the same factor? and the skin around its legs? what about the specialised structures in the jugular to slow blood flow, and is skin tissue, muslce and veins all part of the same control factor? i highly doubt it sinnce in the papers i read on the girrafe it is not mentioned.

While this might seem like proof of an intelligent designer, by incorporating a 'fail safe' also consider that it is the 'simplest' way of arranging things. And while you might wonder why evolution would favour this over an alternative approach, stop and consider the implications of any alternative.

Well i think there are alot more things in nature that scream intelligence then this but i get your point.

There are two options available to us - dependant devlopment, or independant development of the vertebrae and nerves. I am suggesting that the information we have available shows that the development of both is dependant on some third factor (the Hox Genes), with the net result being the illusion of co-evolution, and this being the simplest way of doing things.

you are suggesting? is it true or not? and again, heart, muscle, tissue, veins, nerve, bone, skin strapped aournd legs? I doubt all of this is controlled by a single hox gene?





[/quote]How long is a Giraffe with a spinal cord that's too short for its neck going to survive. The answer is, it probably isn't. It's probably going to die at an early age, due to the spinal cord being severed, or pulling the brain down into the spinal colum.

and indeed we should expect it too die rather then expect such a miraculous coevolution of parts..This of course speaks nothing about the specialised reite mandilbe in its head, was that in its ancestosr? i dont know but im sure many mammals have such a structure. Did this coevolve wtih the growing arteries?

Similar arguments, incidentally, can be made for the heart size, and blood pressure 'issues' as well.

Giraffe bloodpressure (presumably) follows a normal distribution about some mean value (same for heart size).

As neck length increases over time, those Giraffes that might ordinarly have been hypertensive, are going to find themselves being more successful with greater frequency than those with 'mean' blood pressure, and those giraffes with long necks, that would ordinarily have been hypotensive are probably going to be the least succesfull, and are probably going to find themselves prey pretty quickly.[/quote]

there is a big difference between beign a bit hypersenstiive to have the blood pressure a girrafe has now. Lets just say though that there was the odd hypersensitive girrafe? would that blood pressure have been enough for the grwoing neck? or would that also have to "keep up"..
surely we cant suggest that as the heart grew, that tight leg strapping also coevolved to those veins from becoming smush!

So we end up with a regime where

Long Neck, Low blood pressure < Average Neck, Average Blood pressure < Long neck, Average blood pressure < Long neck, high blood pressure.

The net effect being that evolutionary pressures, combined with physiological requirements are going to select for those Girrafes with long necks and high blood pressure.

there is a big differenec in "selecting" for long necks and high blood pressure, we still have to get to the point girrafes are at now, and simply selecting does not set sometign on the road to higher complexity, it just selects it, we are still invoking here a miraculous coevolution of parts and i personally wont do such a thing yet. I mean, wow, that is a real miracle.

And please, you'll note that I only made two initial assumptions:
1. That Giraffe blood pressure exists accross a range of values.
2. That Giraffe neck length has increased.
And from those two assumptions, we have effectively explained the co-evolution of girraffe blood pressure, and Girraffe neck length.
Girraffes with neck lengths above the population mean, and blood pressure below the population mean probably weren't even able to stand up, and so probably became prey quickly.
Giraffes with neck lengths and blood pressures around the population means, were as successful as every other giraffe.
Giraffes with neck lengths around the population mean, but blood pressures above it, were no more or less successfull than the rest of the population.
Giraffes with neck lengths above the population mean, but blood pressures around the population mean were slightly more successful, because they could reach more food, but may have had the occasional bought of giddyness.
Giraffes with neck lengths and blood pressures above the population mean were the most successful, because they reach more food, and did not have the bouts of light headedness to deal with - this may even have given them an advantage over those from the previous groups, because they would be able to keep their necks erect more.

speculation based on what you alredy think occured does not actually explain anything, it simply gives your opinion. and you of course left out the strapped skin, veins, tissues, tendons, muscles and even things like the lymphatic system would have to coevolve, and this is only the tip of the iceberg. My next post wont be for a while but it will be about the faith of coevolution(Im not saying it didnt happen just that there is far too much faith, far too little evidence, far too much extrapolation, far too little cirtical thinking, and this isnt even getting into creatures that separatly coevolevd to suit each other, or predator prey relationthips. I think you'll be intersted in what i have to say)

No Magic, no mystery, just a trait that was already in the population giving a slight advantage.

it all depends on how you define magic and mystery. Since its not a fact and you only tried to explain away very few details from the full picture then indeed it is still a mystery. But, if it turns out it did happen exactly as you say, and the same for the sexes etc then there is no other word for it then miraculous, and that is in some sense magical..

You need to get out of thinking that simply having an prior advantage(higher then avarge blood pressure, slihgly longer neck) will lead you to higher(coevolving) complexities..

 

[Zenithar66]

As long as you dismiss evidence of lack of intelligence in design, trying to claim that all apparent design problems are somehow mysteriously purposeful in ways beyond our understanding, you are not employing a theory: you are evangelizing belief in an entity beyond reason or contradiction - a deity.

Scientific theory can be falsified, contradicted by evidence and reason. That's probably (cf Karl Hopper) its basic characteristic.

again i have invoke not diety nor do i harbour a belief in one. Does that mean i cant suspect design?

 

[Zenithar66]

You are laboring under a misconception. Evolution does not work like this. It's not that when a species changes, every individual part of the species has to mutate separately. That's absurd. We simply had giraffes with shorter necks, and giraffes with slightly longer necks, just like you can see people that are shorter or taller. DNA does not contain a blueprint for every individual organ, it's precise size, irrespective of the other parts. Some parameters are guided by overall growing guidelines while the creature is still an embryo.

Please do some further research on the topic before you pretend to know what you are talking about.

what exactly are you talking about? indeed there ARE many instances where features that are separated did have to(by evolutionary thoery) coevolve, are you saying co evolution doesnt happen?

"That's absurd. We simply had giraffes with shorter necks, and giraffes with slightly longer necks, just like you can see people that are shorter or taller."

wow, so that explains it, we had girrafes with shorter and longer necks, ahh now i get it? wait...then what? they didnt end up as what they are now? oh wait, the did, and oh, that required a coevolution of parts!!

 

[Zenithar66]

You keep discussing 'coevolution' [coevolution is a real term but NOT as you are defining it] as if this is a real term. Your use of the term 'coevolution' is essentially a made up definition that adds a false complexity to the situation to make it seem implausible. Trippy had a very good post about giraffe evolution and why there is no 'coevolution' just good old fasion regular evolution.

my term refers to the coevolution of parts in either single species or in both sexes or in a symbiotic or predator prey relationship.

Here is a very simplistic explanation. There is a population of proto-giraffes. Like all populations there is a range of heights and sizes. During drought conditions food becomes scarce and the animals with the longer necks could reach the leaves higher in the trees and they survived to pass on their genes.
There is no 'coevolution' needed. The heart and nerves did not evolve indepedently. The larger animals simply had larger hearts and longer nerves due to there size, kind of obvious. Large animals with long necks and small hearts equal lion food. The large animals with long necks and strong hearts equal breeding animals - simple.

your right it is simplistic, but its also adds nothing to the conversation.
You are essentially saying that those girrafes etc wtih longer necks or bigger heart are selected...uh how does this explain what a girrafe is like now? unless you assume that early girrafes already had all of this stuff in place?

selected a bigger heart or neck simply makes that the prevailign theme in a species population, it doesnt explain how it got to 26 pounds!! or how the legs would have exploded with no strapping, or that indeed everthing in the neck had to actually grow, not just be selected, to get to where we are now! any scientist will tell you that the girrafe has changed ALOT from when "selection" t acted on them in the dawn of the species....they have evolved, and coevolution seems the only solution as to how the species have not died out, that is of course if you buy such a miraculous event...

simple question...does coevolution of parts occur in nature in the present or the past?

Evolution works on populations that are already here this is why giraffes have the same number of neck vertibrae that other mammals do. If a designer was in charge it would make much more sense to toss in a few more vertibrae. Nature does not have that luxury.

again this simply explains the selection process, not how the changes occured that get selected..
and what is this desinger stuff? if this and if that? if indeed there is a designer or designers or whatever we cant assume to know anything about him/her/them or there motives so theres no need to try to keep saying oh look a desinger wouldnt do it this way since that is incredulity and assumption...

I simply admit,as of yet, i see no explanation becuase coevolution is too much of a stretch of credibilty..

 

[spidergoat]

You are misusing the term co-evolution. It's not that every organ evolves independently. I think I already pointed that out. Basically, environmental forces determined that larger and larger giraffes were necessary for survival, so that's what we have now. It's an accumulation of natural selection events that favored long-necked giraffes. I guess you don't know that some genes affect large scale changes? How is it that some people are born giants? Why don't only their bones grow long and everything else stays the same? Why does everything else grow big too?

You seem to be suggesting that for a giant to be born, every individual organ has to miraculously undergo an entirely separate and unlikely mutation!

selected a bigger heart or neck simply makes that the prevailign theme in a species population, it doesnt explain how it got to 26 pounds!

Yes it does! That's exactly what it explains!

 

[Zenithar66]

You are misusing the term co-evolution. It's not that every organ evolves independently. I think I already pointed that out. Basically, environmental forces determined that larger and larger giraffes were necessary for survival, so that's what we have now.

when i refert to coevolution i mean parts of a body, or of speices taht smply had to "keep up" in terms of evolution or else there would be no animal today, how you cant see this is beyond me!

It's an accumulation of natural selection events that favored long-necked giraffes. I guess you don't know that some genes affect large scale changes? How is it that some people are born giants? Why don't only their bones grow long and everything else stays the same? Why does everything else grow big too?

so SOME genes affectl large scale changes? does this apply to the girrafes skin, veins, lymph system, bones, nerves, heart, and arteries?
are you suggseting that nothing in the girrafe had to co evolve?

You seem to be suggesting that for a giant to be born, every individual organ has to miraculously undergo an entirely separate and unlikely mutation!

nope that would simply be a mistake in the already made recipe.





Yes it does! That's exactly what it explains![/QUOTE]

nope, that dosent explain anything except that selection occured on PREVIOUSLY EXISTING FEATURES, but where do you think new changse come from to be selected? mutations! a word you didnt use much..
as the neck grew longer via(not just sexual/natural ) selction but mutations, everthing else had to keep up, simple as that, and if you infer this indeed did occur then it is a coevolution of parts and also a pure miracle that i have as of yet got no faith in...

 

[billvon]

Ive seen many intelligent compromises from an engeneering standpoint.

Yes, and there have been many stupid compromises. "Compromise" itself is not intelligent or dumb.

its subjective....yet you clearly think you can pick out bad design?

No, and that's the whole point. The only "bad design" in an evolutionary sense is one that kills the organism before it reproduces.

your supposed mistake in the eye is also ignoring the fact that the eye is one the most coplex, mind blowing, co ordinated and miraculous things in the known universe.

It's pretty cool, yes. It could be higher resolution, more sensitive to light, more resilient to aging, more resistant to separated retinas etc etc. But the key is that it's good ENOUGH.

Is it mind blowing? To you, perhaps. To others, not so much. That's a subjective judgment.

again, it is an argument for incredulity saying that the reitina is backwards, therefore bad design.

I said it was good _enough_.

Why be so quick to presuem there is no reason for such design?
From what i no about nature i would much more reasonably think there is a reason until proved otherwise..

Oh I absolutely think there's a reason! It happened to evolve that way and it worked well enough.

you cannot get blood up that neck without a 2 foot heart!

Right. So the first long neck, due to that first mutation, is only 6 inches longer. The proto-giraffes with marginal hearts do sorta OK, the ones with weak hearts die, the ones with stronger hearts do quite well. Do that for ten thousand years and all the giraffes now have slightly stronger hearts.

you cannot surive unless your leg skin is strapped as tight as hell to stop blood vessels popping

Right. So that proto-giraffe with the six inch longer neck has some examples with slightly tighter skin, some with slightly looser, some average. Again, the loose skin proto-giraffes die out, and in ten thousand years, they have slightly stronger leg skin.

Etc etc.

there simply HAD to be a coevolution of a great number of parts of the girrafe, do you deny this?

Yes. But here's the key - they did not have to happen all at once. Evolution moves in fits and starts, a bit at a time.

a pain in the neck? so if you heart didnt keep up with your neck what then? a pain in the chest?

Yes. And the weak-hearted proto-giraffes would die.

a pain in the neck is alot different then getting a mutation to make your neck bone longer without the muscles, veins, nerves, lymph system etc followign suit, alot different indeed.

As I am sure you are aware, people born with unusually long legs do not have inch-long gaps where the muscles, veins, nerves, lymph systems etc did not grow long enough. The genes that code for development do not code for "make a nerve nineteen inches long" - they code for "grow from this chemical gradient to that chemical gradient until you see another gradient."

That's why even humans can be born with unusually long necks. For us there's generally no advantage so it's not selected for.

Co evolution, or rather the many structures claimed to have done so, is one of the best evidences against teh mechanisms in my opinion since you are basically invoking a miracle!

It only looks like a miracle when you look at the end result of 100 million years of evolution. When you look at it over the course of a few hundred years it is very mundane indeed. (Although it is very cool that we can actually see it happening today.)

 

[billvon]

so SOME genes affectl large scale changes?

Yes. Google "HOX genes." Those are like master switches that code for where arms, legs, eyes etc go. You can make just a few changes to them, for example, and replace a fruit fly's antennae with legs.

What's cool about that is you don't have to tell the organism "make more exoskeleton, make the muscles a millimeter longer, make the curve of the leg just so." The HOX gene just turns on leg expression at that point, and leg development starts in a new place.

does this apply to the girrafes skin, veins, lymph system, bones, nerves, heart, and arteries?

You don't need to change any other genes to make those things work. As I mentioned before, some humans have longer legs. Usually their skin, veins, lymph systems, nerves, arteries etc have no problem growing along the longer limb.

nope, that dosent explain anything except that selection occured on PREVIOUSLY EXISTING FEATURES, but where do you think new changse come from to be selected? mutations! a word you didnt use much.. as the neck grew longer via(not just sexual/natural ) selction but mutations, everthing else had to keep up, simple as that, and if you infer this indeed did occur then it is a coevolution of parts and also a pure miracle that i have as of yet got no faith in...

Yes, everything else did have to keep up. And the "miracle" that allowed that to happen is that all the organisms that could NOT keep up died. Which seems pretty cruel for a miracle, but it's how evolution works.

 

[Zenithar66]

[/quote]Yes, and there have been many stupid compromises. "Compromise" itself is not intelligent or dumb.

unless of course the compromise is intelligent or dumb!

It's pretty cool, yes. It could be higher resolution, more sensitive to light, more resilient to aging, more resistant to separated retinas etc etc. But the key is that it's good ENOUGH./

oh yes and why dont we have uv vision too! its perfect for what we are, your actaully seem to be making it soudn bad? which is beyond comprehinsion to me, we may as well ask for 4 arms...the eye is staggering thing and we have in no way fully understood it.

Is it mind blowing? To you, perhaps. To others, not so much. That's a subjective judgment.

I'd say it is mind numbing infact its one of the most delicate yet complex and coordinated things in the universe so you'd have to be pretty dead inside , as in zombie dead, not to apprecaite that. It should be even more amazing to those convinced of the mechanissm by which it "came about".

I said it was good _enough_.

Its not just good enough, its much more then that. It is much better then waht is needed to merely survive.. any way i suppose its subjective.

Oh I absolutely think there's a reason! It happened to evolve that way and it worked well enough.

yes i know you think you know but well..

Right. So the first long neck, due to that first mutation, is only 6 inches longer. The proto-giraffes with marginal hearts do sorta OK, the ones with weak hearts die, the ones with stronger hearts do quite well. Do that for ten thousand years and all the giraffes now have slightly stronger hearts.

nope you dont just keep "doing that for 10000 years" that is simply selection! you need new material to work with in order to get where we are now(intersting side note, i just thought of this, are there any fossils for the girrafes neck getting longer? Maybe would could glean some info form them?)...you need mutatins in order to not only select, but make changes and evolve.

Right. So that proto-giraffe with the six inch longer neck has some examples with slightly tighter skin, some with slightly looser, some average. Again, the loose skin proto-giraffes die out, and in ten thousand years, they have slightly stronger leg skin.

again you are literally making up a story here to fit with what you belive, i wont do that. and again "those with tighter skin" had to, over evoltuion, not just be selected again and again, but get progressibly tigher skin AS THE BLOOD PRESSURE ROSE as the heart grew! which is a miracle.


Etc etc.

Yes. But here's the key - they did not have to happen all at once. Evolution moves in fits and starts, a bit at a time.

of course not all at once, but many many still had to "keep up" and that, again, is miraculous. even the trachea would grow substantaily along with the neck!

Yes. And the weak-hearted proto-giraffes would die.

while magical coevolution continued on its merry way eh?

As I am sure you are aware, people born with unusually long legs do not have inch-long gaps where the muscles, veins, nerves, lymph systems etc did not grow long enough. The genes that code for development do not code for "make a nerve nineteen inches long" - they code for "grow from this chemical gradient to that chemical gradient until you see another gradient."

soooo...

That's why even humans can be born with unusually long necks. For us there's generally no advantage so it's not selected for.

oh that explains the coevoution of parts needed for teh girrafe, now it clear to me.

It only looks like a miracle when you look at the end result of 100 million years of evolution. When you look at it over the course of a few hundred years it is very mundane indeed. (Although it is very cool that we can actually see it happening today.)

you mean you THINK it happened this way..how can you seriously belive that any part of any organisms(dont even start me on sexes since they are totally independent mutationally) would ever keep up over long periods. you are invokign a constant series of miraculous events!