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Evidence of Evolution Options
kisholoy mukherjee
Posted: Saturday, September 25, 2010 7:31:45 AM
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There have been some threads on this topic, but let this one be entirely or primarily dedicated to whether this theory is true or false or more aptly, what evidence is there in favor of it and against it.
This is a good place to start.
http://evolution.berkeley.edu/evolibrary/search/topicbrowse2.php?topic_id=46
HWNN1961
Posted: Saturday, September 25, 2010 11:37:18 AM
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As one who is rather convinced that the preponderance of evidence shows that the theory is on the right track, I'll sit back and read thoughts from others on the topic.
Cat
Posted: Saturday, September 25, 2010 11:49:36 AM

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km, I would ask you to clarify what you're wanting to discuss. I highlighted in red where "new species" is used. I think it also important to be clear on what, exactly is meant by "species" in your thread. Otherwise tangents will destroy this discussion, in my opinion.

Also, you supplied a link that I went to and found too much information. How about if you start with your opinion and/or synopsis to get us started on what you want to discuss exactly. I think evolution is too broad.

Cat

From TFD:

evolution (v-lshn)

1. The process by which species of organisms arise from earlier life forms and undergo change over time through natural selection. The modern understanding of the origins of species is based on the theories of Charles Darwin combined with a modern knowledge of genetics based on the work of Gregor Mendel. Darwin observed there is a certain amount of variation of traits or characteristics among the different individuals belonging to a population. Some of these traits confer fitness they allow the individual organism that possesses them to survive in their environment better than other individuals who do not possess them and to leave more offspring. The offspring then inherit the beneficial traits, and over time the adaptive trait spreads through the population. In twentieth century, the development of the the science of genetics helped explain the origin of the variation of the traits between individual organisms and the way in which they are passed from generation to generation. This basic model of evolution has since been further refined, and the role of genetic drift and sexual selection in the evolution of populations has been recognized. See also natural selection sexual selection See Notes at adaptation Darwin Charles Robert

2. A process of development and change from one state to another, as of the universe in its development through time.

A Closer Look Darwin's theory of evolution by natural selection assumed that tiny adaptations occur in organisms constantly over millions of years. Gradually, a new species develops that is distinct from its ancestors. In the 1970s, however, biologists Niles Eldridge and Stephen Jay Gould proposed that evolution by natural selection may not have been such a smooth and consistent process. Based on fossils from around the world that showed the abrupt appearance of new species, Eldridge and Gould suggested that evolution is better described through punctuated equilibrium. That is, for long periods of time species remain virtually unchanged, not even gradually adapting. They are in equilibrium, in balance with the environment. But when confronted with environmental challenges, sudden climate change, for example, organisms adapt quite quickly, perhaps in only a few thousand years. These active periods are punctuations, after which a new equilibrium exists and species remain stable until the next punctuation.

species [ˈspiːʃiːz (Latin) ˈspiːʃɪˌiːz]
n pl -cies
1. (Life Sciences & Allied Applications / Biology) Biology
a. any of the taxonomic groups into which a genus is divided, the members of which are capable of interbreeding: often containing subspecies, varieties, or races. A species is designated in italics by the genus name followed by the specific name, for example Felis domesticus (the domestic cat) Abbreviation sp
b. the animals of such a group
c. any group of related animals or plants not necessarily of this taxonomic rank
2. (Life Sciences & Allied Applications / Botany) (modifier) denoting a plant that is a natural member of a species rather than a hybrid or cultivar a species clematis
3. (Philosophy / Logic) Logic a group of objects or individuals, all sharing at least one common attribute, that forms a subdivision of a genus
4. a kind, sort, or variety a species of treachery
5. (Christianity / Ecclesiastical Terms) Chiefly RC Church the outward form of the bread and wine in the Eucharist
6. Obsolete an outward appearance or form
7. Obsolete specie

abcxyz
Posted: Saturday, September 25, 2010 11:55:00 AM
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I'm a supporter of the theory of evolution. Among a lot of other signs, human foetus in its early stages bears stunning similarity with its evolution-related species. Existence of vestigial organs, fossils of the now extinct apes which were supposed to be our ancestors substantiate the claim of evolutionists. Further, evolutionists have been able to successfully guess the existence of certain species whose fossils were found later. I don't think anyone can say for sure that the theory of evolution is a perfectly sound one, it may have its flaws, but it is a far better one than Adam and Eve fornicating after eating an apple and currently the best one we have.
MarySM
Posted: Saturday, September 25, 2010 11:56:13 AM
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How any rational, educated, adult human can deny evolution amazes me. However we currently have a candidate for the office of Senator from Delaware who insists that evolution is a myth. I guess those that agree will vote for Christine O’Donnell. I actually spoke with an adult who insisted that dinosaurs never existed and it was all a “plot” to convince people the bible is wrong. This conversation ended abruptly and badly!
peterhewett
Posted: Saturday, September 25, 2010 12:24:33 PM
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Marysm wondered:

How any rational, educated, adult human can deny evolution amazes me

peter says:

I am such and individual Marysm, or so all my friends would say, but I do not believe in evolution, and I wonder how one can, but am prepared to let them have their view and respect them, while I hold to mine. It is good to show respect for anothers view don't you think?


Adaptation is not evolution, and at some point, after I see how this discussion goes, I will post on that. Let's see some folk commit themselves with 'proof' first and not speculation.


I will not google for my posts... I have studied the subject both sides and will use at these references stored in my documents folder and some dvd's I have loaded.
kisholoy mukherjee
Posted: Saturday, September 25, 2010 12:29:20 PM
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Cat wrote:
km, I would ask you to clarify what you're wanting to discuss.


I am wanting to discuss the evidences in support of or against the theory of evolution (as in biology).

Cat wrote:

I highlighted in red where "new species" is used. I think it also important to be clear on what, exactly is meant by "species" in your thread. Otherwise tangents will destroy this discussion, in my opinion.


There was no mention of the word 'species' in my thread. Evolution in general, is what I meant.


Cat
Posted: Saturday, September 25, 2010 12:49:17 PM

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I repeat:

km, I would ask you to clarify what you're wanting to discuss. I highlighted in red where "new species" is used. This is part of the definition TFD has for evolution. So if you want to discuss evolution I believe a definition is necessary because "adaptation" and "evolution" are often used interchangeably. New species from adaptation is, I think, what you are after. Is that your definition of evolution for your post?.

I think it also important to be clear on what, exactly is meant by "species" in your thread. Otherwise tangents will destroy this discussion, in my opinion. I suggest this because, again, variations in birds do not imply new species. I am not a biologist so I need these pedantic definitions to understand the argument.

Also, you supplied a link that I went to and found too much information. How about if you start with your opinion and/or synopsis to get us started on what you want to discuss exactly. I think evolution is too broad. Please. Pray

Cat
peterhewett
Posted: Saturday, September 25, 2010 12:51:51 PM
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I think it is posted in the wrong section... Philosophy and Religion would have been more fitting.
kisholoy mukherjee
Posted: Saturday, September 25, 2010 1:12:06 PM
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abcxyz wrote:
I'm a supporter of the theory of evolution. Among a lot of other signs, human foetus in its early stages bears stunning similarity with its evolution-related species. Existence of vestigial organs, fossils of the now extinct apes which were supposed to be our ancestors substantiate the claim of evolutionists. Further, evolutionists have been able to successfully guess the existence of certain species whose fossils were found later. I don't think anyone can say for sure that the theory of evolution is a perfectly sound one, it may have its flaws, but it is a far better one than Adam and Eve fornicating after eating an apple and currently the best one we have.


And there can be experiments too which show evolution in a population:

"John Endler of the University of California has conducted experiments with the guppies of Trinidad that clearly show selection at work. The scenario: Female guppies prefer colorful males for mating purposes. Predatory fish also "prefer" colorful males, but for a less complimentary purpose — a source of food that is easy to spot. Some portions of the streams where guppies live have fewer predators than others and in these locations the males are more colorful (top frame). Not surprisingly, males in locations where there are more predators tend to be less colorful (bottom frame).

When Dr. Endler transferred predatory fish to the regions with brightly colored male guppies, selection acted rapidly to produce a population of duller males. This demonstrates that persistent variation within a population provides the raw material for rapid evolution when environmental conditions change.
"

http://evolution.berkeley.edu/evolibrary/article/0_0_0/lines_15
peterhewett
Posted: Saturday, September 25, 2010 1:18:48 PM
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Abcxyz. The Bible makes no mention of an apple.

Organs that seem not to be used do not prove evolution... it needs to prove the forming of new ones.

They used to tell us the thymus gland was a vestigal organ until it was discovered to play an important part in stemming infection. Vestigal organs so called are organs for which the function has yet to be discovered. the Thymus gland was one example of this.

So called 'vestigal' organs do not in the least prove evolution.



KM This point is rather null and void.

When Dr. Endler transferred predatory fish to the regions with brightly colored male guppies, selection acted rapidly to produce a population of duller males. This demonstrates that persistent variation within a population provides the raw material for rapid evolution when environmental conditions change."

Peter says: Variation does not prove evolution, it merely shows that there is a capacity for adaptation which is not evolution... they were still fish. That is not an example of evolution no more than tapping the gene sequence in roses to produce different colours is... they are still roses.

Duller males were already there and survived in numbers because of it, they did not change into a different creatures or grow or lose limbs and the process could be reversed since the capacity to colour up is still in the genes. You example is a poor one and does not prove evolution and is not an example of it.

The capacity for variation does not prove evolution in the least. I will come back to this at a later point.


Evolution must prove the forming of new organs not resort to adaptation which is to grasp at straws.
abcxyz
Posted: Saturday, September 25, 2010 1:18:51 PM
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KM, yes, that's a good example of how evolution works.
abcxyz
Posted: Saturday, September 25, 2010 1:35:49 PM
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peterhewett wrote:
Abcxyz. The Bible makes no mention of an apple. Organs that seem not to be used do not prove evolution ..it needs to prove the forming of new ones.


I did not say vestigial organs 'prove' evolution, I said they are signs of evolution. The organs due to lack of use became as they are now. All this is in accordance with the theory of evolution.

Evolution is a long process and takes millions and millions of years, it is not like today mosquitoes are bugging me and tomorrow I'll sprout a tail. So it is hard to prove evolution, but there are plenty of signs of it.
abcxyz
Posted: Saturday, September 25, 2010 1:38:53 PM
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PH, it would be interesting to hear your alternative of evolution.
peterhewett
Posted: Saturday, September 25, 2010 1:43:22 PM
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b][You said Abcxyz[/b]

The organs due to lack of use became as they are now. All this is in accordance with the theory of evolution.


peter says: No...you are wrong. You made no reference to my point about the thymus gland did you Abcxyz. And what about the tonsils that used to be called a vestigal organ but now is viewed as important to ward off infection?


Just because we do not know the use of an organ it does not mean that it has no use does it. You are assuming that they have gone out of use... assumptions will not do... they do not prove evolution and the idea that time will solve all its problems is a fallacy.
peterhewett
Posted: Saturday, September 25, 2010 1:45:52 PM
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Abc said:

PH, it would be interesting to hear your alternative of evolution.

peter says:

This is not the thread for such I think but at some point perhaps.
MarySM
Posted: Saturday, September 25, 2010 1:56:45 PM
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I apologize peterhewett. Although I don't understand why or how, I concede some intelligent individuals may believe evolution is a "myth."
abcxyz
Posted: Saturday, September 25, 2010 1:57:55 PM
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peterhewett wrote:
[b]You said Abcxyz[/b]

The organs due to lack of use became as they are now. All this is in accordance with the theory of evolution.


peter says: No...you are wrong. You made no reference to my point about the thymus gland did you Abcxyz. And what about the tonsils that used to be called a vestigal organ but now is viewed as important to ward off infection?


There are still the appendix, the cartilage of the ear, the coccyx etc. Everyone knows someone who had their appendix removed. But I know that still does not prove that these have absolutely no use at all, but one organ which was initially thought to be vestigial turning out to be useful doesn't disprove the existence of vestigial organs.
AnthA1G
Posted: Saturday, September 25, 2010 2:36:22 PM

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Ok Peter we got it, you don't think any of the evidence proves evolution. In your opinion it's not evolution, it is rather adaptation. But, can you please just stop "confronting" any evidence presented in this thread? You don't have to be a biologist or scientist to attack the theory of evolution. But for god's sake, you got to at least understand scientific theory.Pray

This is not an attack, BTW. I just want you to use science and logic as your tools, not mere beliefs.

Thanks for starting the thread, KM.
abcxyz
Posted: Saturday, September 25, 2010 3:07:40 PM
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Peter says: Variation does not prove evolution, it merely shows that there is a capacity for adaptation which is not evolution... they were still fish. That is not an example of evolution no more than tapping the gene sequence in roses to produce different colours is... they are still roses.

The experiment shows that the fish are capable of changing their colour through adaptation. On that site there is an example of sparrows changing their size. So it can be experimentally shown that animals and fish are capable of adaptation. Now, if you compare the anatomy of the primates and the homo sapiens you'll see that the basic organ and bone structure is the same. So it wouldn't be completely illogical to think that if fish can adapt themselves so quickly, 6 million years of adaptation can turn an anthropoid into a human or a chimpanzee, depending on their habitat. We even have the fossils of many of their intermediate stages.

If we go further back, there were proto-primates which had very similar structure as the primates. These proto-primates were again similar to some ancient mammals from whom the human is structurally more different than the primates. It is therefore a logical assumption(not yet proven) that structurally similar animals share a common ancestor. Now until and unless in the unlikely case a better theory replaces it this is the best one we have.

The acceptability of a theory is correlated with how well it can explain the phenomena concerned and how many predictions it can make with high degree of accuracy. With evolution we have been able to successfully guess the existence of certain species and explained a lot of biological phenomena. As far as my knowledge goes, no alternative theory has this success.
bturpin
Posted: Saturday, September 25, 2010 3:20:09 PM
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MarySM wrote:
I actually spoke with an adult who insisted that dinosaurs never existed and it was all a “plot” to convince people the bible is wrong. This conversation ended abruptly and badly!


I have heard about these people mary but have never met one myself. I once saw something on the History or Discovery channel about a man who takes people into the Grand Canyon and "scientifically" show people the canyon is only a couple thousand years old and how certain formations were placed there specifically using horribly inaccurate data about rock compositions and formations. I think it's safe to say that these types of people are a danger to the educated world.
kisholoy mukherjee
Posted: Saturday, September 25, 2010 3:38:02 PM
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Thanks Anth, for the encouragement. I hope this thread will have an educational debate on evolution.
abc...great points. I will post some more later.
Christine
Posted: Saturday, September 25, 2010 10:38:38 PM
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I thought all dogs came from wolves.
HWNN1961
Posted: Saturday, September 25, 2010 10:42:41 PM
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Evolution, creation.

It's all one.

It's all the same.

Evolution does not preclude God.

It EXPLAINS him.

Why is this so friggin' difficult to grasp?
excaelis
Posted: Sunday, September 26, 2010 12:11:29 AM

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I'm a little confused as to where adaptation differs from evolution.
AnthA1G
Posted: Sunday, September 26, 2010 12:41:25 AM

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excaelis wrote:
I'm a little confused as to where adaptation differs from evolution.


Some people think organisms can adapt to certain extent without actually evolving into another species. All in all, they don't think we were once another specie (like some primate or something)...Think Think Think
excaelis
Posted: Sunday, September 26, 2010 1:00:34 AM

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Thanks Anth. I think that helps.
peterhewett
Posted: Sunday, September 26, 2010 1:44:34 AM
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Abc... you said: one organ which was initially thought to be vestigial turning out to be useful doesn't disprove the existence of vestigial organs.

I reply. But it is more than one organ the tonsils were also considered a vestigial organ until they were discoverd to form an inpotant role in staving off infection. There are others too and there is division over the appendix. See as follows:


Well, you know medical science sometimes changes and now scientists indicate in the recent online version of the Journal of Evolutionary Biology that the appendix, often thought to have no real medical value, does have its benefits after all. I don’t have my appendix anymore after its removal by a surgery (appendectomy) in 1981, due to acute appendicitis. It is estimated that millions of people don’t have their appendix after surgical removal.

Dr. William Parker, an immunologist at Duke University Medical Center in Durham, N.C., and his colleagues suggest that the vermiform appendix serves to repopulate the gut with good bacteria after a bad case of diarrhea, by being a store chest of good bacteria.


Quote: It was found that the coccyx situated at the lower end of the vertebral column supports the bones around the pelvis and is the convergence point of some small muscles and for this reason, it would not be possible to sit comfortably without a coccyx.unquote.



Besides which the apparent non-use of an organ does not prove in the least evolution, or/and the forming of new organs does it? It is pure speculation, not scientific proof.

The fact that one can survive with out an organ does not in anyway support, or even lend support to the theory of evolution. We can survive with out legs and arms... all of them... and exist as a torso can we not? Evolution is charged with the proving of new forms of life ...development of new organs etc, not clutching at straws by making false claims that certain organs are vestigial. Indeed it has to prove life started from non-life... now that is a great leap.

NB. An ape has an appendix whereas creatures below it do not.
peterhewett
Posted: Sunday, September 26, 2010 1:58:03 AM
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excaelis wrote:

I'm a little confused as to where adaptation differs from evolution.


Peter replies.

I will post on this at a later time.
peterhewett
Posted: Sunday, September 26, 2010 2:17:25 AM
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Anth said this:

Ok Peter we got it, you don't think any of the evidence proves evolution. In your opinion it's not evolution, it is rather adaptation. But, can you please just stop "confronting" any evidence presented in this thread? You don't have to be a biologist or scientist to attack the theory of evolution. But for god's sake, you got to at least understand scientific theory.

I reply:

I will most certainly confront all I wish to confront without seeking the permission of a young boy such as yourself, who shows gross disrespect and seeks to censor viewpoints.

You are once more lowering the tone Anth and should behave yourself.

I know far more about the subject than you, and understand perfectly the theory, so do not be so insolent... stop spoiling the discussion by trolling.

If you have anything to contribute then contribute it and do not personalise the discussion please. WE? Dont assume you speak for every one else that is arrogance. Show respect.


I am entering into the spirit of the OP as follows:

'There have been some threads on this topic, but let this one be entirely or primarily dedicated to whether this theory is true or false or more aptly, what evidence is there in favor of it and against it.'

You should do the same and stop showing disrespect to your elders or to anyone on this forum.


kisholoy mukherjee
Posted: Sunday, September 26, 2010 9:16:33 AM
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Peter said:
"Indeed it has to prove life started from non-life... now that is a great leap."

I wonder how much that fits the definition of evolution that is used by the scientists.

I am quoting from a standard textbook on evolution, by Mark Ridley:

" Evolution means change, change in form and behavior of organisms between generations. The forms of organisms, at all levels from DNA sequences to macroscopic morphology and social behavior, can be modified from those of their ancestors during evolution. ....
Most of the processes in this book concern change between generations within a population of a species and it is this kind of change we shall call evolution. When the members of a population breed and produce the next generation, we can imagine a lineage of populations, made up of a series of populations through time. Each population is ancestral to the descendant population in the next generation: a lineage is an "ancestor-descendant" series of populations. Evolution is then change between generations within a population lineage. Darwin defined evolution as "descent with modification" and the word "descent" refers to the way evolutionary modification takes place in a series of populations that are descended from one another. Recently, Harrison (2001) defined evolution as "change over time via descent with modification".
"

No where does it mention that evolution deals with the "proof that life started from non-life". Evolution seeks to explain ""change over time via descent with modification"" but not how life started. Other, still contested theories about how life started seek to find how life originated.

There are the primordial soup theory, the pizza theory, the sandwich theory etc.

However, that is off-topic. So it is better we stick to evolution meaning change of life forms over time only.

Now coming to the need of evolution to prove forming of new species: That question is certainly valid.
Here is what Mark Ridley says in his online tutorial:

" The evidence for evolution - Can the formation of a new species be observed?

Two concepts of species

We can now consider evidence for the evolution of new species. Most of the evidence so far has been for small-scale change within a species: house sparrows from all over North America are still classified as house sparrows, the same species as was introduced in the 1850s.

The amounts of artificially selected change in pigeons and other domestic animals borders on the species level, but to decide whether the species barrier has been crossed we need a concept of what a biological species is.

What does it mean to say a new species has evolved?

The question lacks a simple answer that would satisfy all biologists. We can take two of the most important species concepts and see for each what the evidence for the evolution of a new species is.

• One important species concept is reproductive, and defines a species as a set of organisms that interbreed among themselves but do not breed with members of other species. Humans (Homo sapiens ) are a separate reproductive species from the common chimpanzee (Pan troglodytes ) like the one pictured opposite: any human can interbreed with any other human (of appropriate sex), but not with a chimp.

• The second important concept uses phenotypic appearance: it defines a species as a set of organisms that are sufficiently similar to one another and sufficiently different from members of other species. Again, humans and common chimpanzees belong to different species, and they are clearly distinct in phenotypic appearance.

Because some biologists reject one or other concept, we should look at the evidence for the evolution of new species according to both concepts.

Can artificial selection be used to create new species?

What degree of difference, in taxonomic terms, has been produced by artificial selection in domestic animals? There are two answers, depending on what criteria a species is defined:

• Artificial selection has not produced much evidence for new reproductive species: most domestic dogs are interfertile and belong to the same species in a reproductive sense.

• The answer is different for the species concept based upon phenotypic appearance. Take the variety of dogs (Canis familiaris). To most human observers, the difference between extreme forms, such as a pekinese and a labrador, is much greater than that between two species in nature, such as a wolf (pictured opposite) and a jackal, or even two species in different genera, such as a wolf and an African hunting dog (Lycaon pictus).

The evidence from domestic animals suggests that artificial selection can produce extensive change in phenotypic appearance - enough to produce new species and even new genera - but has not produced much evidence for new reproductive species.
"

He further goes on to describe ring species which can "... provide important evidence for evolution, because they show that intra-specific differences can be large enough to produce an inter-species difference. The differences between species are therefore the same in kind (though not in degree) as the differences between individuals, and populations, within a species."

Now, since the definition of evolution says """change over time via descent with modification"" does it mean that because evolution of NEW species cannot be usually seen because they take too long to be seen in our lifetime, the theory is false? This is what Ridley says:

""The time available for humans to observe evolution actually happening is short, but a number of cases have been recorded in which a natural population of a species has changed in form over time. The kettlewell moth is the most famous example of this, but evolution in American house sparrows is also a good illustration""

He then goes on to give illustrations of the European house sparrow Passer domesticus, which after spreading in population underwent evolutionary change, i.e. as per definition, change in 'form' with respect to size, color etc. The changes have been recorded and documented and well illustrated by figures and statistical data.

Mark Ridley goes on to say : "This example contradicts species fixity

The variation in North American house sparrows has all evolved since 1852, when their common ancestors lived, all looking much like this sparrow opposite; the variation has taken a period of about 100 generations or less. The modern array of forms is all classified within one species; but the example shows how a noticeable amount of change can occur within the relatively short time that humans have been making observations.

The variation we see now must have arisen by change within populations through time; the spread of the population across North America was observable, and it can hardly be argued that each population, with its distinct size and color pattern, was separately created.
"

This example fits the definition of "change over time via descent with modification".

Descent - because it is within the same lineage of populations, and modification and change are obvious.

Moreover,

"Evolution can also be observed when it is artificially created:

Evolution can be produced in the laboratory with artificial selection experiments. In a typical experiment, a new generation is formed by allowing only a selected minority of the current generation to breed. The population will almost always respond: the average in the next generation will have moved in the selected direction.

The procedure is used in agriculture: artificial selection has been used to alter the numbers of eggs laid by hens, the meat properties of bullocks, and the milk yield of cows. In an experiment, rats were selected for increased or decreased susceptibility to dental caries on a controlled diet. As the graph shows, the rats could be successfully selected to grow better or worse teeth. Evolutionary change can therefore be generated artificially.
"

As for that experiment on guppies:

That is a very famous experiment, Peter. The link from which I had taken it did not give the full details, so the confusion whether the duller males were already there in the region where the more predators were introduced arose. Now, it should be clearer:

http://www.pbs.org/wgbh/evolution/sex/guppy/

"The guppy feature is very engaging, encouraging the learner to generate simulated guppy populations of varying composition, under different selective pressures, and to consider multiple hypotheses. I generated several virtual guppy populations. I first started with a population evenly divided between drab and colorful male guppies. I cut the simulation off after just four generations, and the population was fairly evenly distributed across a spectrum from drab to colorful male fish. I ran the same starting parameters again and this time went for lunch. After 64 generations (3,228 simulated weeks), I had 220 guppies in my pool, and they were now 100% maximally drab because of intense predatory pressure. For another experiment, I started with a population of drab males and weak predation pressure. I wandered down the hall for a meeting, and when I returned, 521 virtual weeks later, 15 generations had passed, and all the drab fish had been replaced with brilliant progeny. These virtual experiments could be useful student exercises and good supplements to wet-lab experiments."

From: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1200773/

That is all for the moment. There is a lot to discuss on just the above material only.
And here is a video of Richard Dawkins talking about the importance of theory of evolution:

http://www.youtube.com/watch?v=I-QWv_0Mjq0&feature=player_embedded
Cat
Posted: Sunday, September 26, 2010 9:36:36 AM

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I read Darwin's "On The Origin of Species By Means of Natural Selection" when this topic came up previously. I wanted to read for myself what he wrote, not what was written about what he wrote. He theorized NEW species resulting from many small increments of adaptations over a long period of time.

So I have concluded that evolution involves adaptations but adaptations do not presume a new species evolution.

He was troubled by the exclusion of a god from his theory as his wife was religious. If I were to talk with him, I'd tell him that he could preserve his/her belief in god by thinking of god creating the building blocks and "evolution" taking the building blocks and making species from them.

Maybe god's plan was to start with building blocks and see how HIS idea would pan out? Maybe god's plan is to see how fast we can destroy ourselves after we have evolved into ourselves.

I'm still on the fence saying "not enough evidence to determine either way". The reason for this is that we can keep a body alive with machines at this point, but if the body can't stay alive on its own, it dies. We cannot give "life" to person or an animal that is dead.
peterhewett
Posted: Sunday, September 26, 2010 10:50:31 AM
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KM the experimant may well be famous but that in itself proves nothing.

Nothing changes the guppy experiment is meaningless. They did not develop anything. The duller fish survived because of circumstances... nothing evolved… the capacity to colour and to dull down was already there and was still in both fish at the end of the so called experiment.... it proves nothing at all.

Every form of life has the capacity for adaptation that is not evolution at all. One can go forward and backward… play around with genes as they do in wheat and roses etc. Wheat remains wheat and roses remain roses… guppies remain guppies… nothing new is developed. So Guppies have the capacity to change colour… so what… so do chameleons. The experiment is not a proof of evolution. That is such a weak claim and is easily dismissed… it is clutching at straws.

Back to wheat.

One can cross and develop one can take genes and change the yield potential, the disease resistance, the height and strength of the straw, and so on. But what is important is that it remains wheat and is not a new species or an example of evolution. The capacity for variety within the wheat was already there and was not developed. You can do the same with anything and roses are another example.

All creation has capacity for variety including the human family… adaptation is not evolution. It does not explain the development of the brain the heart the circularity system etc. etc. etc.

The idea that life sprung from non-life in an integral part of evolutionary thinking since many evolutionists, probably most are also atheists, and it is dishonest to try and make a separation.

If you cannot prove life began of itself then evolution is a non-starter.
abcxyz
Posted: Sunday, September 26, 2010 10:51:55 AM
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kisholoy mukherjee wrote:
abc...great points.

Thanks KM, and nice post by the way.

HWNN, the theory of evolution is independent of god.

I'm yet to see any evidence against evolution in this thread. PH, what would you call 'scientific proof'? We postulate from observation and intuition. Every scientific theory has some assumption as the basis. Assuming evolution do you see how beautifully everything else fits in? Please see my previous post in this thread.

As for the appendix and the other 85 vestigial organs being useful, there are debates among people, and even if we discover some minor uses of them that still does not prove that they are not 'souvenirs' of organs which had some important role in our evolutionary ancestor's body. Besides we all know how religion blinds people of reason. The humiliation of Galileo and Copernicus, the murder of Bruno are examples of it. Who knows whether these 'there-is-no-vestigial-organ' people are motivated by science and not religion?
peterhewett
Posted: Sunday, September 26, 2010 10:55:05 AM
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Abc.. I am not going to put forth an argument for creation in this thread but am going to post in line with the OP : 'let this one be entirely or primarily dedicated to whether this theory is true or false or more aptly, what evidence is there in favor of it and against it.'


I am from time to time just going to challenge what is put forward as evidence for evolution. I respect your right to your view, but challenge it with vigour, not rancour.

I do not believe in the theory of evolution.

Abx you lost the argument on vestigial organs... be graceful and concede that it is not evidence of evolution. Let us not bring religion into this discussion or the prejudices against it. This thread is not about religion... lets stick to the subject. I do not follow a religion.
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