Scientific theory and people's ignorance of it's definition.

[Synthetix]

"A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world. The theory of biological evolution is more than "just a theory." It is as factual an explanation of the universe as the atomic theory of matter or the germ theory of disease. Our understanding of gravity is still a work in progress. But the phenomenon of gravity, like evolution, is an accepted fact."

-American Association for the Advancement of Science.



Many people, creationists in particular, seem vary unaware of what a theory actually is. When someone says, "evolution is just a theory, though", they seem to be implying that it's a good guess at best. As said above, a theory is an explanation that is backed with a mountain of facts/evidence. When did the definition of a theory, or more specifically a scientific theory, become lost and/or misunderstood?

 

[SpaceYeti]

Equivocation. It's that easy. Creationists aren't interested in truth or facts, so they'll use whatever trick they can think of to make a convincing (if not accurate or honest) argument.

 

[EyeSeeCold]

It has a degenerated popular usage, but that's typical of pop-culture; the general person doesn't care enough to research trivial information such as the history of terminology.

The meaning of "(scientific) theory" hasn't changed in the scientific community where it matters the most, though, anyway.



Specifically though, I'd guess the advent of the internet with "conspiracy theories".

 

[Synthetix]

Are you saying the spread of conspiracy theories via the interwebz has a role to play in the ignorance of scientific theory within the general population? Could you explain this for me.


What many don't realize is that a theory must be tested and the results of the test must be synonymous with the theory. If one test out of even a million tests is contrary to the theory, then the theory is wrong. This would be different than the phenomenon that the theory describes, however. The phenomenon of evolution, gravity, etc are facts.

 

[Chad]

Hypothesis

A hypothesis is an educated guess, based on observation. Usually, a hypothesis can be supported or refuted through experimentation or more observation. A hypothesis can be dis-proven, but not proven to be true.



Theory

A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing. A theory is valid as long as there is no evidence to dispute it. Therefore, theories can be dis-proven. Basically, if evidence accumulates to support a hypothesis, then the hypothesis can become accepted as a good explanation of a phenomenon. One definition of a theory is to say it's an accepted hypothesis.



Law

A law generalizes a body of observations. At the time it is made, no exceptions have been found to a law. Scientific laws explain things, but they do not describe them. One way to tell a law and a theory apart is to ask if the description gives you a means to explain 'why'.



I don't agree with Creationism either but most scientific theories get dis-proven in time. This is just the nature of science. I agree with many of the observable facts of evolution its the theoretical leaps that seem unprovable to me. Thus as a whole it is the best current theory but it is not inflatable.

 

[Absurdity]

I don't agree with Creationism either but most scientific theories get dis-proven in time. This is just the nature of science. I agree with many of the observable facts of evolution its the theoretical leaps that seem unprovable to me. Thus as a whole it is the best current theory but it is not inflatable.

My understanding is that evolution is an observable phenomenon in the fossil record.

The only thing up for debate is the means by which it occurs, i.e. Natural Selection.

 

[Chad]

My understanding is that evolution is an observable phenomenon in the fossil record.

The only thing up for debate is the means by which it occurs, i.e. Natural Selection.

From what I know the fossil record isn't perfect (unless the found all the missing links and no one bothered to tell me). It shows relatively speaking some life existed before the known existence of other life. I can consider that this is likely the case.

Natural Selection has been proven to cause diversity among species and this is by far the most tested part of the theory. I actually have no problem with the theory of natural selection. Its it does explain the natural phenomenon of who a species location and environment could cause so much diversity.

However, it doesn't create the necessary link to cross species.

Even if viral and bacterial evolution which would arguably be must faster then malti-celled evolution has never happened. We have never seen a virus be anything other then a living or dead virus. They change and they adapt but they are always viruses. Maybe they have accomplished this recently I don't know.

Also the big question for evolution is how does carbon and other non organic chemicals suddenly form organic molecules. Seriously, we can even do this artificially yet. The only hypothesis ever presented was later to be discovered as a fraud. (Fraud is actually very present among evolutionary mostly because there are so many facts to the theory that we don't even know how to test them yet).

I am not here to say that evolution didn't happen. Maybe it did. I am sure Creationism didn't happen at least not in the way they present it today.

 

[Synthetix]

From what I know the fossil record isn't perfect (unless the found all the missing links and no one bothered to tell me). It shows relatively speaking some life existed before the known existence of other life. I can consider that this is likely the case.

Natural Selection has been proven to cause diversity among species and this is by far the most tested part of the theory. I actually have no problem with the theory of natural selection. Its it does explain the natural phenomenon of who a species location and environment could cause so much diversity.

However, it doesn't create the necessary link to cross species.

Even if viral and bacterial evolution which would arguably be must faster then malti-celled evolution has never happened. We have never seen a virus be anything other then a living or dead virus. They change and they adapt but they are always viruses. Maybe they have accomplished this recently I don't know.

Also the big question for evolution is how does carbon and other non organic chemicals suddenly form organic molecules. Seriously, we can even do this artificially yet. The only hypothesis ever presented was later to be discovered as a fraud. (Fraud is actually very present among evolutionary mostly because there are so many facts to the theory that we don't even know how to test them yet).

Which hypothesis was that?

I am not here to say that evolution didn't happen. Maybe it did. I am sure Creationism didn't happen at least not in the way they present it today.

Evolution does happen, how it happens may still be debatable but it does happen. I can't yet say the same for creationism. I've heard though, that evolution must take place before there can be intelligent design, not the other way around. This isn't a proven fact, but it seems more logical than evolution happening after intelligent design.

 

[Brontosaurie]

it is very important to note that science does not differ from guessing in principle. the text you quote tries but fails to make an essential distinction between science and non-science. it really only succeeds in blaming the reader for not "getting it" when there's nothing to get. poorly worded and obsolete.

 

[Chad]

Which hypothesis was that?




Evolution does happen, how it happens may still be debatable but it does happen. I can't yet say the same for creationism. I've heard though, that evolution must take place before there can be intelligent design, not the other way around. This isn't a proven fact, but it seems more logical than evolution happening after intelligent design.

Possibly I am not here to defend either theory on to play devils advocate. I like many of the ideas behind Evolution. Some of them seem less plausible but as a whole like I said its the best we have right now.

 

[Synthetix]

it is very important to note that science does not differ from guessing in principle. the text you quote tries but fails to make an essential distinction between science and non-science. it really only succeeds in blaming the reader for not "getting it" when there's nothing to get. poorly worded and obsolete.

There is an immense difference between science and guessing. Theories have been tested ad nauseum. In science, theories are formed from these facts to help us better understand factual phenomena. If you believe it to be poorly worded and obsolete, then what would your definition be?

 

[scorpiomover]

"A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world. The theory of biological evolution is more than "just a theory." It is as factual an explanation of the universe as the atomic theory of matter or the germ theory of disease. Our understanding of gravity is still a work in progress. But the phenomenon of gravity, like evolution, is an accepted fact."

-American Association for the Advancement of Science.

Many people, creationists in particular, seem vary unaware of what a theory actually is. When someone says, "evolution is just a theory, though", they seem to be implying that it's a good guess at best. As said above, a theory is an explanation that is backed with a mountain of facts/evidence. When did the definition of a theory, or more specifically a scientific theory, become lost and/or misunderstood?

A possible explanation is:

When public education about science and politics was introduced, and when everyone got TV.

Before then, no-one was taught any science in school, unless you were part of the elite, or you were one of the very, very few, who would be given a scholarship for a better life. Everyone else went to work by 16 at the latest, and it was common for them to work 12 hours a day. There wasn't time to question or learn that much about science. Even if you had the time, you didn't have access to the material for self-study. It didn't matter if a theory was just a postulation, or an accepted fact. Only other scientists and members of the elite could question it. Most of the elite didn't want to mess with the system that helped them so much. Scientists didn't want to risk their positions by saying the wrong thing, to end up in a working-class job down the mines. So most scientists also didn't want to publicise anything that might rock the boat. The rest didn't have the knowledge to even begin to question it. On top, in those times, everyone was encouraged to accept people in authority as experts who knew far more than you did. It didn't matter if they were doctors, lawyers, religious leaders, scientists, policemen, or politicians. Everyone was respected in their field of authority.

Now, almost everyone in a Western country, has been educated by public education and TV. They've been encouraged to question almost all forms of authority, including politicians, policemen, religious leaders, lawyers, doctors, and scientists. Moreover, they've been educated so much about science, that they have the ability to form questions and challenges about scientific theories. Moreover, people only work 8 hours a day now, and only 5 days a week, and on top, they don't have to slog their guts out. People aren't knackered by the end of the day anymore. They have the time and energy to question as well. All that gives people the ability to question if scientific theories are correct.

There are consequences to everything. Some are what you hoped for. Some are unexpectedly in your favour. Some are unexpectedly against you.

I expect that scientists probably thought that if everyone was educated about science, then they'd all back scientists to the hilt. It was hoplessly over-optimistic, because the only reason that people didn't argue in the past, was because they couldn't, coupled with a huge amount of propganda designed to back government, that also made people back scientists out of ignorance. They'd never really been in the situation where large numbers of laypeople had the ability to challenge them, and the belief that it wasn't wrong to challenge them. So they weren't used to having to answer millions of people's questions and problems with their theories.

They imagined a utopia in their favour, and forgot to consider what might happen if things didn't turn out like they hoped. So they weren't prepared for the consquences, and they still haven't learned to adapt yet. Instead, they've tried to close ranks, and retreat into appeals to them as authorities. But that doesn't work any more either, because the desire to listen to authorities, is not science-dependent. When people stopped accepting what bankers and politicians said, they rejected the notion of appeal to authority, and with it, rejected the automatic authority of scientists as well.

This is what happens when things change. Some things adapt, some adapt slower, and those that are slow to adapt, receive evolutionary pressures. It's evolution happening in the present day.

 

[Duxwing]

From what I know the fossil record isn't perfect (unless the found all the missing links and no one bothered to tell me). It shows relatively speaking some life existed before the known existence of other life. I can consider that this is likely the case.

Natural Selection has been proven to cause diversity among species and this is by far the most tested part of the theory. I actually have no problem with the theory of natural selection. Its it does explain the natural phenomenon of who a species location and environment could cause so much diversity.

However, it doesn't create the necessary link to cross species.

That's not something that evolutionary theory predicts. It simply predicts that, all conditions remaining the same, that each successive generation of a given population of organisms will be slightly better adapted to the conditions of that population's environment because those organisms that didn't adapt died before reproducing, thereby 'culling' maladaptive traits.

Even if viral and bacterial evolution which would arguably be must faster then malti-celled evolution has never happened. We have never seen a virus be anything other then a living or dead virus. They change and they adapt but they are always viruses. Maybe they have accomplished this recently I don't know.

And that's exactly what evolutionary theory predicts. You're just confused about how populations of organisms adapt to their environments: they do so very slowly over thousands of generations, each one slightly different from the last. No organism one evolves. It's not something that one can 'do'. It's an effect observed when comparing generations of organisms,.

You can see evolution in this made-up table of bird beak lengths, wherein birds with longer beaks are better able to reach food in the trunks of trees:

Generation, Average Beak Length (mm)
1, 2
2, 2.01
3, 2.02
4, 2.03
5, 2.04
...
100, 3.0

Every bird's beak length is fixed, but those birds with longer beaks can eat more food and are therefore more likely to survive and pass their genes-- and therefore their traits-- on to the next generation, and the opposite is true for birds with shorter ones. And if you'd examine the fossil record of this population, then you wouldn't see a bird with a beak suddenly extending. Rather, you'd see that birds higher up in the rock containing the fossils (higher fossils being more recent) had longer beaks.

That's evolution by natural selection.

Also the big question for evolution is how does carbon and other non organic chemicals suddenly form organic molecules. Seriously, we can even do this artificially yet.

Lightning in the clouds, comet impacts, random collisions: A billion years is plenty of time for the craziest stuff to happen.

The only hypothesis ever presented was later to be discovered as a fraud. (Fraud is actually very present among evolutionary mostly because there are so many facts to the theory that we don't even know how to test them yet).

What the heck? Fraud how? Where?

-Duxwing

 

[Chad]

That's not something that evolutionary theory predicts. It simply predicts that, all conditions remaining the same, that each successive generation of a given population of organisms will be slightly better adapted to the conditions of that population's environment because those organisms that didn't adapt died before reproducing, thereby 'culling' maladaptive traits.



And that's exactly what evolutionary theory predicts. You're just confused about how populations of organisms adapt to their environments: they do so very slowly over thousands of generations, each one slightly different from the last. No organism one evolves. It's not something that one can 'do'. It's an effect observed when comparing generations of organisms,.

You can see evolution in this made-up table of bird beak lengths, wherein birds with longer beaks are better able to reach food in the trunks of trees:

Generation, Average Beak Length (mm)
1, 2
2, 2.01
3, 2.02
4, 2.03
5, 2.04
...
100, 3.0

Every bird's beak length is fixed, but those birds with longer beaks can eat more food and are therefore more likely to survive and pass their genes-- and therefore their traits-- on to the next generation, and the opposite is true for birds with shorter ones. And if you'd examine the fossil record of this population, then you wouldn't see a bird with a beak suddenly extending. Rather, you'd see that birds higher up in the rock containing the fossils (higher fossils being more recent) had longer beaks.

That's evolution by natural selection.



Lightning in the clouds, comet impacts, random collisions: A billion years is plenty of time for the craziest stuff to happen.



What the heck? Fraud how? Where?

-Duxwing

I understand how the theory works my understanding of it is not lacking. I explained natural seleciton in my post anyway. However, natural section has never been proven to change a one species into another one even over many many generations. This has been tried with single celled organisms that can have several thousand generations in one day. At the end of the day the are still the same species just with a few new traits. At the end of a year (millions of generations) they still haven't changed enough to not be recognizable as the same species. Some of these types of test have been going on for years and years still without any validated results. I personally seen a test were they had over 1 billion generations where the some traits changed back and forth but no nothing signification enough to classify said organism as a new speices form the original organisms in the test.

This is why I think its funny when geologist. Says that the earth is only 4 billions years old but. When if we were evolutionary involved form some other creatures would be about 200,000,000 generations form the beginning of the earth.

Yes, some of the smaller single single celled life forms reproduced much quicker. However, the time it would be needed to change one multi-celled species into another one. Not to mention all of them. Would be must longer then we believe the earth to be.

I actually am not misunderstanding principles and I agree that they work on a inter species level. I just have no reason to believe that macro external species natural selection ever works. There is not proof on theoretical hypothesis.

Hypothesis are educated guess based off known facts. We know that natural selection happens all the time. We know that we are here. So you put two and two together and you assume that we are here based off of natural selection.

Like someone else said we also know that somethings existed before others. This is the evidence in the fossils. Evolution tries to explain this.

And there may be truth to it. However, there is something else at play here. Either the earth is much much older then we thought before Evolution happens faster at sum stages of the earth history for reasons we don't actually know.

Thus it is the best known theory and it has been proven wrong just like the age of the earth being 4 billion years old is just a theory and hasn't been proven wrong.

One explanation is that one of the theories is wrong as they seem to contradict or third unknown principle at play that we have yet to discover.

However since both theories are not dis-proven they both still exist.

I am not hear to dis-prove Evolution. I am hear to present questions that evolution can not explain as of right now. May it can some day or maybe it will be replaced with a better theory who knows.

 

[Brontosaurie]

There is an immense difference between science and guessing. Theories have been tested ad nauseum. In science, theories are formed from these facts to help us better understand factual phenomena. If you believe it to be poorly worded and obsolete, then what would your definition be?

yes, theory has been scrutinized and verified. but there is no valid discrete demarcation between science and non-science. the very point is to understand that science is, positively, essentially, a flexible estimation and the best available guess, rather than vacuum-seal it and conserve it in a protective foam of dogma. the difference between science and religion - the rejection of arbitrary demarcation, suspension of judgment.

(falsificationism basically)

 

[Duxwing]

I understand how the theory works my understanding of it is not lacking. I explained natural seleciton in my post anyway. However, natural section has never been proven to change a one species into another one even over many many generations. This has been tried with single celled organisms that can have several thousand generations in one day. At the end of the day the are still the same species just with a few new traits. At the end of a year (millions of generations) they still haven't changed enough to not be recognizable as the same species. Some of these types of test have been going on for years and years still without any validated results. I personally seen a test were they had over 1 billion generations where the some traits changed back and forth but no nothing signification enough to classify said organism as a new speices form the original organisms in the test.

That sounds about right. Single-celled organisms can reproduce quite easily, even if radically different.

This is why I think its funny when geologist. Says that the earth is only 4 billions years old but. When if we were evolutionary involved form some other creatures would be about 200,000,000 generations form the beginning of the earth.

Yes, some of the smaller single single celled life forms reproduced much quicker. However, the time it would be needed to change one multi-celled species into another one. Not to mention all of them. Would be must longer then we believe the earth to be.

I actually am not misunderstanding principles and I agree that they work on a inter species level. I just have no reason to believe that macro external species natural selection ever works. There is not proof on theoretical hypothesis.

Hypothesis are educated guess based off known facts. We know that natural selection happens all the time. We know that we are here. So you put two and two together and you assume that we are here based off of natural selection.

Like someone else said we also know that somethings existed before others. This is the evidence in the fossils. Evolution tries to explain this.

And there may be truth to it. However, there is something else at play here. Either the earth is much much older then we thought before Evolution happens faster at sum stages of the earth history for reasons we don't actually know.

Thus it is the best known theory and it has been proven wrong just like the age of the earth being 4 billion years old is just a theory and hasn't been proven wrong.

One explanation is that one of the theories is wrong as they seem to contradict or third unknown principle at play that we have yet to discover.

However since both theories are not dis-proven they both still exist.

I am not hear to dis-prove Evolution. I am hear to present questions that evolution can not explain as of right now. May it can some day or maybe it will be replaced with a better theory who knows.

Multicellular evolution can be observed in the fossil record. Consider giraffes, whose long necks evolved to reach leaves. They were once much shorter (and we can verify this in the fossil record) but now they're longer. Evolution at work.

-Duxwing

 

[WookieeB]

Multicellular evolution can be observed in the fossil record. Consider giraffes, whose long necks evolved to reach leaves. They were once much shorter (and we can verify this in the fossil record) but now they're longer. Evolution at work.

-Duxwing

Umm, nope. The "long necks to reach the leaves' is a supposition with no evidence at all. A just-so story. Besides, there are SO many problems with this supposition vs reality.

Giraffe cows are on average a full meter shorter than bulls.
Offspring are significantly much shorter.
Ignores migration possibilities
Ignores other grass eating animals existing.
Ignores a host of other developmental changes that would have to accompany neck length extension.
There are no giraffe fossils showing gradual change in neck length
Supposed short-necked giraffe ancestors (not giraffes) existed simultaneously with 'long neck' giraffes

I'm with Chad on this one

 

[Duxwing]

Umm, nope. The "long necks to reach the leaves' is a supposition with no evidence at all. A just-so story. Besides, there are SO many problems with this supposition vs reality.

Taller giraffes ate better.

Giraffe cows are on average a full meter shorter than bulls.

So? Tree length still affects neck length because cows that are too short perish. Not all trees are of the same height, either.

Offspring are significantly much shorter.

Ever hear of lactation?

Ignores migration possibilities

Where to? Where from?

Ignores other grass eating animals existing.

Ever hear of evolutionary niches?

Ignores a host of other developmental changes that would have to accompany neck length extension.

Which are present in modern day giraffes and arose by natural selection.

There are no giraffe fossils showing gradual change in neck length

To the contrary:http://en.m.wikipedia.org/wiki/Giraffe#section_2

Moreover, why must the fossils exhibiting progressively longer necks be of the giraffe species?

Supposed short-necked giraffe ancestors (not giraffes) existed simultaneously with 'long neck' giraffes

Again, I point to the theory of evolutionary niches, which allows both to exist because one eats grasses and the other eats leaves.

-Duxwing

 

[Chad]

If this is your source for the information you suggested you are miss reading it. "The giraffe is one of only two living species of the family Giraffidae, the other being the okapi. The family was once much more extensive, with over 10 fossil genera described. Giraffids first arose 8 million years ago (mya) in south-central Europe during the Miocene epoch. The superfamily Giraffoidea, together with the family Antilocapridae (whose only extant species is the pronghorn), evolved from the extinct family Palaeomerycidae.[9] The earliest known giraffid was the deer-like Climacoceras. While the progressive elongation of the neck and limbs can be found throughout the giraffid lineage, it became more pronounced in genera such as Giraffokeryx, Palaeotragus (possible ancestor of the okapi), Samotherium, and Bohlinia.[9]Bohlinia entered China and northern India in response to climate change. From here, the genus Giraffa evolved and, around 7 mya, entered Africa. Further climate changes caused the extinction of the Asian giraffes, while the African ones survived and radiated into several new species. G. camelopardalis arose around 1 mya in eastern Africa during the Pleistocene.[9] Some biologists suggest that the modern giraffe descended from G. jumae;[10] others find G. gracilis a more likely candidate.[9] The main driver for the evolution of the giraffes is believed to have been the change from extensive forests to more open habitats, which began 8 mya.[9] Some researchers have hypothesized this new habitat with a different diet, including Acacia, may have exposed giraffe ancestors to toxins that caused higher mutation rates and a higher rate of evolution.[11] The giraffe was one of the many species first described by Carl Linnaeus in 1758. He gave it the binomial name Cervus camelopardalis. Morten Thrane Brünnich classified the genus Giraffa in 1772.[12] In the early 19th century, Jean-Baptiste Lamarck believed the giraffe's long neck was an "acquired characteristic", developed as generations of ancestral giraffes strived to reach the leaves of tall trees.[13] This theory was eventually rejected, and scientists now believe the giraffe's neck arose through Darwinian natural selection—that ancestral giraffes with long necks thereby had a competitive advantage that better enabled them to reproduce and pass on their genes." These are all sub species of closely related to Giraffes. They are not Giraffes with different length limbs over history like you presented in your post. There is natural selection involved here but it related to location not time.

 

[Reluctantly]

What many don't realize is that a theory must be tested and the results of the test must be synonymous with the theory. If one test out of even a million tests is contrary to the theory, then the theory is wrong. This would be different than the phenomenon that the theory describes, however. The phenomenon of evolution, gravity, etc are facts.

Evolution does happen, how it happens may still be debatable but it does happen. I can't yet say the same for creationism. I've heard though, that evolution must take place before there can be intelligent design, not the other way around. This isn't a proven fact, but it seems more logical than evolution happening after intelligent design.

There is an immense difference between science and guessing. Theories have been tested ad nauseum. In science, theories are formed from these facts to help us better understand factual phenomena. If you believe it to be poorly worded and obsolete, then what would your definition be?

In the spirit of Nil, someone I've greatly appreciated for sharing his wisdom...

EVENT
A giraffe crosses a river <-> This explains how the event occurs
A giraffe crossed the river to get fruit from a nearby tree because it was hungry <-> This explains why the event occurs

How the event occurs can be used to justify why; however, why the event occurs involves interpretation. That may not be "why" from the giraffe's mind, but if it always happens, one might decide it is "true" nonetheless. And when something is interpreted, the facts are then used in service of the interpretation and not against it. Then whether a fact proves or disproves the interpretation is up to the individual... The Big Bang theory, Evolution, etc. all fall into this trap... the very "how" used to support them can be used to support creationism or any other idea of "why".

Science isn't perfect...

@Synthetix

 

[WookieeB]

Taller giraffes ate better.

Evidence for this? None. Just a story concocted to fit a presupposed belief.

I find it interesting that not even all scientists that do believe in evolution of the giraffe agree that your reason was the 'advantage' for long necks. There are suggestions that it was maybe due to it making harder for predators to attack giraffes, to sexual selection.

So? Tree length still affects neck length because cows that are too short perish. Not all trees are of the same height, either.

But according to your reasoning the cows eat less better.

Or if not all trees are of the same height, then whatever supposed advantage of longer necks is proportionally less.

So, then there were trees of varying heights to serve both cows and bulls, but there was some limit on other food sources of other heights, including ground level? No evidence for that either, so I wonder where is the advantage of longer necks?

Ever hear of lactation?

Really? You are suggesting that child giraffe's lactate until they are tall enough to reach the trees? Haha! Regardless the amusement of the idea, there is no evidence for your supposition.

Where to? Where from?

If neck length gives a food advantage, that would conversely imply that shorter necks give a food disadvantage. For one, there is no evidence to suggest that a giraffe survived better than any shorter animals. But even if that were the case, if food was better or more plentiful up high, animals with a limit of food lower would more likely migrate somewhere to where food is more abundant, or die out if there isnt food elsewhere. There is no way to gain any 'advantage" until the neck is already longer. No reason to select a longer neck, unless you are suggesting natural selection knew ahead of time its need.

Ever hear of evolutionary niches?

Irrelevant. This is a thinly veiled attempt to assign some form of teleology to NS. Plus it presupposes that the giraffe already evolved for the reasons you give above, all of which there is NO evidence for.

Which are present in modern day giraffes and arose by natural selection.

Here you are are begging the question.

How fortuitous for the giraffe to evolve completely independent biological systems all to prop up an advantage to longer necks. Of course this had to happen before there was any advantage, otherwise what is the point?

To the contrary:http://en.m.wikipedia.org/wiki/Giraffe#section_2

Moreover, why must the fossils exhibiting progressively longer necks be of the giraffe species?

It's so easy to just link a wikipedia article. Problem is, the link doesn't provide any evidence to support your assertion. IT states:

While the progressive elongation of the neck and limbs can be found throughout the giraffid lineage, it became more pronounced in genera such as Giraffokeryx, Palaeotragus (possible ancestor of the okapi), Samotherium, and Bohlinia

Problem is, excepting Bohlinia, none of those fossils demonstrate any elongation of the neck. Bohlinia, already has a long neck, and is not really any transition species.

see HERE in section 3 for a discussion of the fossils

Again, I point to the theory of evolutionary niches, which allows both to exist because one eats grasses and the other eats leaves.

Again, irrelevant. Plus, I think you are missing the point. If the giraffe is living amongst it's supposed ancestors, then they are really not the giraffe ancestors. Plus, there is no 'advantage' to having a longer neck with regards to feeding.

 

[SpaceYeti]

Really? You are suggesting that child giraffe's lactate until they are tall enough to reach the trees? Haha! Regardless the amusement of the idea, there is no evidence for your supposition.

Please tell me there was some sort of mistake in typing made on your part, and you're not this stupid. Nobody's this stupid. You can't be this stupid.

 

[WookieeB]

Please tell me there was some sort of mistake in typing made on your part, and you're not this stupid. Nobody's this stupid. You can't be this stupid.

Ya, I misstated it. I meant the moms lactating to feed the young giraffes. I didn't proof read that one very well.

But with that cleared up, I still think any mention of lactation is silly.

 

[SpaceYeti]

Ya, I misstated it. I meant the moms lactating to feed the young giraffes. I didn't proof read that one very well.

But with that cleared up, I still think any mention of lactation is silly.

Why?

 

[WookieeB]

Why?

The assertion was that giraffe long necks evolved to reach leaves, which implies an advantage applied to the height of a giraffe for feeding. A short giraffe, like a baby, would be at a disadvantage comparatively to taller giraffes.

Unless I am missing his point, the mention of lactation I assume was meant to imply that a baby giraffe would feed from mothers milk until they grow to reach a sufficient height. Besides there being no evidence for this, I find the thought of an animal needing to nurse until it is tall enough to be silly.

The view that giraffes developed its long neck and legs for an advantage of feeding in trees is portrayed as self-evident in many textbooks and evolutionary stories. It's portrayed as fact and retold over and over again. But it is only a speculative story, and as an explanation is only good if you ignore the behavioral, biological and ecological details. Fortunately, reality doesn't ignore those.

 

[Montresor]

Yeah the giraffe thing is sort of a basic beginner's demonstration of the potential for natural selection of adaptive traits. Something that most people should be able to wrap their heads around - something that is not exactly wrong, but not right either.

I think it's funny that you guys argued about it. It's like a children's story. You make up a lie (false truth) that children can understand so you can start them down the correct path.

Please don't tell the giraffe evolution story to anybody except a child...

 

[SpaceYeti]

The assertion was that giraffe long necks evolved to reach leaves, which implies an advantage applied to the height of a giraffe for feeding. A short giraffe, like a baby, would be at a disadvantage comparatively to taller giraffes.

Unless I am missing his point, the mention of lactation I assume was meant to imply that a baby giraffe would feed from mothers milk until they grow to reach a sufficient height. Besides there being no evidence for this, I find the thought of an animal needing to nurse until it is tall enough to be silly.

The view that giraffes developed its long neck and legs for an advantage of feeding in trees is portrayed as self-evident in many textbooks and evolutionary stories. It's portrayed as fact and retold over and over again. But it is only a speculative story, and as an explanation is only good if you ignore the behavioral, biological and ecological details. Fortunately, reality doesn't ignore those.

There are actually several advantages to a giraffe's height. Eating the leaves and buds of tall trees is only one. I'd say even more important is their ability to scan the savannah's horizon for predators. Giraffes also eat bushes, fruits, and other stuff other herbivores eat. They're simply the lucky ones who, in a pinch, can also get the higher up leaves.

They also use their necks while fighting. Their necks are pretty damn strong, after all. Anyway, while getting higher foods is an advantage, it's almost certainly not the sole advantage for which their long necks were selected for.

 

[Brontosaurie]

vague qualifiers, most likely referring to some fuzzy innate sense of entitlement:

"A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world. The theory of biological evolution is more than "just a theory." It is as factual an explanation of the universe as the atomic theory of matter or the germ theory of disease. Our understanding of gravity is still a work in progress. But the phenomenon of gravity, like evolution, is an accepted fact."

-American Association for the Advancement of Science.

scientist dogma. esotericism. ugly, ugly, ugly, ugly, ugly.

 

[Cherry Cola]

Brontosaurie with da truth

 

[WookieeB]

There are actually several advantages to a giraffe's height. Eating the leaves and buds of tall trees is only one. I'd say even more important is their ability to scan the savannah's horizon for predators. Giraffes also eat bushes, fruits, and other stuff other herbivores eat. They're simply the lucky ones who, in a pinch, can also get the higher up leaves.

They also use their necks while fighting. Their necks are pretty damn strong, after all. Anyway, while getting higher foods is an advantage, it's almost certainly not the sole advantage for which their long necks were selected for.

The problem with this is that it is still just a speculative guess. It is trying to fit an end-result observed status (giraffes have long necks) to some story that can comport with natural selection finding some advantage to it, because well, people figure it had to have happened that way. But there is no evidence to back up those speculations.

Behaviorally it doesn't match up to the theory that eating the leaves from the tops of trees is an advantage. In fact, observations of giraffe's seem to indicate otherwise. They show giraffes tend to eat from the tops of tress more so only during the rainy season when food is plentiful everywhere. During the dry season, they tend to eat more at belly height or lower in a feeding area that overlaps with other animals. They also somewhat migrate to other better-feeding areas in the during the dry season, and there typically eat from plants at lower heights. So in general they do not behave according to a theory that their height (long necks and legs) gives them a feeding advantage to eat from trees higher up.

Height for scanning the horizon is just a guess. Besides, one could just as easily speculate that height would be a disadvantage to a giraffe, making it stick out more, more easily spotted by predators above the brush. Observational data again seems to suggest that the giraffe height isn't an advantage against predators. Lions are well known to attack and kill giraffes, and those attacks are about 50% more often against male giraffes (which are taller) than vs female giraffes.

Long necks for fighting (which is done only by male giraffes) could suggest an aspect of sexual selection. But then you would have to add some teleological aspect to the selection process, since a long neck would in a physical engineering aspect have to reach a length of one to two meters before it could be used in club like fashion. In essence, you need the length there first before it could be selected for as a fighting function.

Biologically, it is more than just longer necks and legs. There are a host of issues relating to blood pressure, musculature, nervous system, reproduction, and more that would have to develop SIMULTANEOUSLY to make the added height viable in the animal at all. That is asking for a lot from NS, and frankly again adds a teleological aspect to it. A host of independent, individual (at least with their core functions) parts have to come together and integrate to support a new physical system.

Perhaps a bit much minutia there, but my point again is that it is easy to come up with a story for why NS must have made something. But unless that can cover the aspects of observed (evidence) in behavioral, biological, physiological and other areas, all it is is a story.

 

[SpaceYeti]

Dude, being able to eat food other animals can't get to is an advantage even if you don't take advantage of it all the time. However, their primary food source is, in fact, acacia leaves, and they prefer the higher leaves which other animals cannot reach, so you're just plain wrong about this point.

Being able to see predators when they're farther away is an advantage even if it also means they sometimes see you sooner, because you can react to them faster. Further, adult giraffes are large and able to defend themselves, making them a poor choice for predators who could go eat something smaller. Yes, they do become prey to lions anyhow, but so what? Being low on the list of choices means them having the advantage of initiative means the lion they saw will more likely eat something besides them, because they reacted fast enough to get out of the lion's AO.

All your other "issues" are... just strange. Obviously if those things didn't keep up with the extended neck and legs, the individual wouldn't be selected for. Duh.

 

[Montresor]

What went wrong: stepping outside of the framework of the thread to nitpick about how a general phenomenon manifests in one species.

I remember something about natural selection being reactive, as in it is always one or two steps behind the current environmental pressures. That's what keeps it going. That's where the energy and momentum come from. Natural selection is always playing "catch-up".