My biology teacher defined it a little different. Evolution is the change of gene frequency over generations. This is in observable fact. The Evolutionary Theory states that the diversity of life on earth is due to evolution. I think the history should be seperate (whether on another page or heading), as it kind of gets in the way of the scientific theory as we now know it. -
Eean
Note, however, that the link contradicts the assertion of "numerous observed cases". The link states: "The literature on observed speciations events is not well organized. I found only a few papers that had an observation of a speciation event as the author's main point."
Note, this does not mean numerous cases have not been observed.
It means that what is surely the most momentous event in biology, the transformation of one species into another, was asserted as the "main point" in only a "few" papers, and was relegated to a lesser status in all other papers. In common usage, "few" does not mean "numerous". In science as it is commonly practiced, researchers do not downplay momentous observations.
The link lists _numerous_ cases.
"The observed fact that speciation in vertebrates results in non-breeding animals explains the complete absence of intermediate forms in the fossil evidence for vertebrate evolution."
The above quoted statement was deleted from this page because someone felt that "he didn't think it made sense". What he means is that he did not agree with it, and so, in the true spirit of scientific debate, he just made it disappear.
I don't think it does make sense. First, non-breeding animals seems to imply mules or such; it should say non-breeding populations. But even in that case, that the final pops are non-breeding doesn't to me explain why there wouldn't be intermediate forms.
- Saying it doesn't make sense greatly understates the case: it is in fact a deliberate lie. Nothing can "explain the absence of intermediate forms" when there are in fact thousands of intermediate forms in the fossil record, and to deny their existence is either painfully ignorant or dishonest. Other opinions have a place here in Wikipedia. Lies and deception do not. --LDC
For instances of transitional vertebrate fossils, see:
http://www.talkorigins.org/faqs/faq-transitional.html
Nonsense will continue to be deleted.
Thus, with force, does Dogma always speak.
---
Dogma my ass. Pointing out evidence that refutes nonsense claims is not dogma. The claim, "of course, speciation has never been observed" is nonsense and was deleted. The claim that there is "a complete absence" of transitional vertebrate fossils is nonsense and was deleted. Stop making up facts. Stop ignoring the evidence. Stop whining when this is not tolerated.
The above link doesn't go anywhere.
Try:
http://www.google.com/search?q=cache:www.talkorigins.org/faqs/faq-transitional.html+transitional+vertebrate+fossils&hl=en
"A theory of evolution is an attempt to scientifically explain how evolution occurs." Both Intelligent Design and Creationism are unscientific attempts to explain evolution (say the majority of biological scientists). It should be stated that these are religious beliefs rather than science, and they should not have such prominence on the page. Calling Natural selection "Darwinism" implies that it is an ideology (like communism/socialism etc...) whereas it is totally scientific and is altered by new evidence that researchers find.
Similarly, just because creationism is "believed by 4 out of 10 Americans" does not have any influence on how scientifically true the theories are. If "4 out of 10" geneticists believed the theory it would have relevance, but nothing like this number do.
I also don't really see the difference between a page on the "Theory of evolution", as opposed to the theory "Evolution".
-- sodium
I'm going to do some major surgery here, because Ed's additions here are more than merely biased, they're just plain wrong. As you correctly point out, creationist theories are not scientific theories at all, and the text here implies that they are. Secondly, the "4 out of 10" claim is not just irrelevant, it's ludicrous. It probably counts everyone who attends some church with a position, and doesn't reflect actual beliefs at all. Even if there are genuine surveys on the issue, the only way to honestly include them here would be to clearly reference their source and the exact questions asked. --LDC
- I did not say that creationist theories are not scientific theories, only that Sudden Creationism is not a scientific theory. I hold Intelligent Design as a scientific hypotheses equal in merit to Darwin's theory that species origianated without divine intervention. If he can mention God, so can I. --Ed Poor
Intelligent design is a legitimate theory, and should be covered. But it is not a scientific one. "Scientific" implies falsifiable, and ID doesn't qualify. --LDC
- Okay, I'll bite. How can we disprove Darwin's hypotheses that God didn't specially create any species in the last 100 million years or so? --Ed Poor
- Darwinian evolution seems to boil down to, "We see new species popping up in the fossil record, and we don't want to give God the credit. Maybe radiation mutated the genes." So, where's the proof for the mutation hypothesis? --Ed Poor
How about something more like, "We can actually see and document changes to DNA from radiation, we can measure the rate of change in bacteria when we apply specific amounts of radiation to them in the lab, and we can measure the rate of background radiation on Earth, and it matches nicely with the rate of change we observe in bacteria on Earth, and it is quite sufficient to explain evolution, so we don't need to make up any other explanations out of whole cloth to account for it." If you're really that ignorant about the facts of science and biology, you shouldn't be criticizing them. Study some real science, prove that you know what you're talking about, and then come back and criticize. We might be more inclined to listen. --LDC
Hmm. Maybe we need an Evolution Debate[?] page.
It would be interesting to have a reference to the survey (e.g. for example where conducted and how many participants). -- HJH
- "Gallup polls have shown that about 45 percent of Americans believe God created living things in their present form a few thousand years ago; about 40 percent believe that things evolved over a long time with God’s guidance; while only a little more than 10 percent accept Darwin’s theory that things evolved through unguided natural selection and random variations." -- quoted from http://www.discovery.org/viewDB/index.php3?program=CRSC&command=view&id=1053 by Ed Poor
The "Discovery Institute" is not a credible source; we need to see the actual Gallup data, including the exact wording of the questions asked and the method of choosing the sample set. --LDC
All of the following iscommentary, and doesn't belong on the main page (or else belongs on
some other page):
Natural selection suggests that a species adapts to changes in the environment, as a result of randomly occurrring genetic mutations. These mutations can alter the individual's physical shape or the inner workings of the body so that organs may change their shape or size or the immune system may develop a different reaction towards disease. After the mutation has occurred, it's up to nature to test that change in real life. If the change benefits the individual, the individual is most likely to have a better chance of survival. Otherwise, the individual will most likely die and the faulty mutation will be discarded. Often these processes last thousands of years due to the slow rate of mutations as well as the lifespan of the individual, although it seems that in some cases evolution can occur unbelievably quickly, within a few generations (Punctuated Equilibrium).
/Talk1
Evolution by natural selection has been observed so many times that it is now considered a fact.
- No, many Darwinists regard Evolution by Random Mutation to be true, but scientists still consider it a theory. Let's not confuse Fact, Theory, and Law. A fact is you see the sun rise and go across the sky. A theory is, e.g., that the sun revolves around a stationary earth; or, that the earth revolves on its axis. A law is, e.g., that a massive object subject to a radial force inversely proportional to the radius will travel in an ellipse. -- Ed Poor
There have been numerous observed cases of speciation, especially in plants (see link (http://www.talkorigins.org/faqs/faq-speciation.html) for more details). Speciation has not been observed per se in vertebrates, although there are numerous examples of no-longer breeding subpopulations.
- I followed that link and found a very long, impenetrable article but no observed cases of speciation in plants. Could you digest that article for me and put the example on the wiki, please? Inquiring minds want to know. --Ed Poor
- Possibly http://www.talkorigins.org/faqs/faq-speciation.html, section 5.0
Would it be fair to define
the theory of evolution in terms of "macroevolution through random variations and natural selection"?
Ed Poor
- That's a reasonable definition of Darwin's theory of evolution. However, "theory of evolution is a general term; Darwin's isn't the only one. It is a common misconception that "evolution", "theory of evolution", "natural selection" and "Darwinism" are all interchangable terms. --Stephen Gilbert
- I am primarily concerned with the definition of the theory of evolution as in the sentence, "Only about 10% of Americans accept the theory of evolution." I believe this refers to the neo-Darwinian synthesis which entails random variations and natural selection, in contrast to creationism and/or intelligent design. Ed Poor
- For that sentence to be true, it would have to involve a defintion that specifically rejected God; but even if you posit a reasonable defintion that would make that sentence true, it would nonetheless be deliberately deceptive and have no place in an encyclopedia. So avoid the problem: don't say that. We already have good coverage of the average American's belief in the Gallup study, which is reported here completely, accurately, and honestly. Besides, since when is the general public's belief about a scientific theory relevant to anything? Science isn't about belief, that's a religious thing. --LDC
- As I said, it is incorrect to say "the theory of evolution". If you say "the Darwinian theory of evolution", your definition is correct. --Stephen Gilbert
- But I'm following the usage in the article: The commonly accepted scientific theory today is called the Neo-Darwinian Synthesis, . . . In popular usage, "the" theory of evolution refers to this or other Darwinian theories. (I'll change, if all agree.) Ed Poor
- I'd like to see one consistent usage of "theory of evolution" throughout the wikipedia. How can we distinguish between any old theory of evolution and "the theory of evolution accepted by science"? Ed Poor
I agree; it's a reasonable definition of one such theory, but I think the text as it currently is is better. --LDC
Talk from Theory of Evolution/Talk1 (only editor found "Conversion Script")
Evolution of new species in a few generations is probably something of an overstatement. The Cambrian Explosion appears to have lasted on the order of 10 to 20 million years. Even if you allow for chains of 100,000 distinct species (surely that is on the high side) between the basal "worms" that left the first Planolites type tracks and the first arthropods, echinoderms, chordates, et. al. that's 100-200 years per species. These are small animals that probably bred more than once a year.
On the other hand, I'm not going to start a war by changing this on my own.
- See also : Theory of evolution
I agree, we need a "Controversies about" page for evolution, since it is a major phenomenon in its own right.
I am not trying to start this debate here, indeed i have no side to take, but i need help. For every attack there is a defense and i have not yet heard the answer for one of the creationist attacks. all i want to know is if someone can point me to it. the attack is the one that states that: complex, interdependant organs and creatures such as the eye, the bombadier beetle, that one toad, and many others could not have come about as a sequence of changes or mutations in any amount of time -- not just because of the sheer complexity, which removes the long time rebuttle -- but because the changes are interdependent and could not have existed seperately without being a destructive defect and being weeded out by natural selection. I wish this attack had a name too (if there is let me know).
Plasticlax
Plasticlax, this is one of the many creationist fallacies[?] used in the arguments against evolution. You can find excellent information on this and other fallacies at the excellent site talk.origins : http://www.talkorigins.org . Specifically, here is a link devoted to explaining precisely the argument that is oft-repeated by creationists[?]: http://www.talkorigins.org/faqs/bombardier.html
Cyde
No doubt one of the biology gurus will come along and explain it more formally in a little while, Plasticlax, but the short and simple answer is that evolution isn't very good at weeding things out unless those things have a marked bad effect. Most variation has very little effect either way. A fanciful example: blue eyes vs brown eyes make no difference to speak of. Ditto blonde hair vs brown hair. Both are (in most climates) neither selected for nor against, and can become common. But then, come an environmental change (the earth is taken over by little green men who hate blue-eyed blondes) the combination is suddenly wiped out. Or (with the reverse environment) suddenly favoured.
Rickard Dawkins in Climbing Mt Improbable deals with this critique at considerable length, and as one of his examples takes the eye, which, it seems, has not simply evolved, but evolved independantly many seperate times - about 30 or 40, if I recall. Tannin
PS: Arrgh: edit conflict - one of the gurus already did!
From something I wrote some time ago in intelligent design about the "eye" argument:
- For example, many biological cells not associated with the senses respond to the presence of light. Most notable of this group are photosynthetic cells of algae and plants. Other very primitive organisms have very rudimentary photoreceptive cells that can only tell the difference between light and dark. These organisms use this primitive sense to orient themselves correctly toward light. Yet other organisms have clusters of these photoreceptive cells that can distinguish crude shapes. Increasing the complexity, number and arrangement of these cells will then yield rudimentary eyes that can recognize certain objects by shape and so on until an eye capable of seeing in color and three dimensions is produced (this has happened at least twice in evolution with the advent of the cephalopod eye and is currently under way with many other animal groups). Each of these steps in the development of a fully functioning eye has modern analogues in the animal kingdom, and each step need only develop through nothing more than natural selection: those animals with a better ability to sense their environment with photoreceptive cells will survive to produce more young than those that don't have this ability, and so on. There is no need for divine intervention of intelligent design, say scientists.
--
mav
And of course the scientists are right :-)
- Always. Until a better theory replaces an old one. :) The point was to offer a scientific explanation for something that ID folk say can only have been made by god. --mav
Thank you all. I think the first answer was most relevant (good link) and i think the best name of the attack is Irreducible complexity (an existing entry). The defense doesn't really have a name, irreducible complexity is simply nowhere to be found in any organisms.
The other data was also very interesting, especially that the eye evolved 30 to 40 times independently. (that sounds interesting but i bet it conflicts with co-existent theories of descendancy... interesting none the less)
ps. and now i see what happens when two people edit at the same time. i love wikipedia!!! --Plasticlax
"Irreducible complexity" is a non-scientific term made up by Michael Behe in trying to argue his point of view. In reality, no such thing exists. Here's a URL for further explanation: http://talkorigins.org/design/faqs/nfl/#irred
Cyde
Just a footnote on independent developments of eyes: When we speak of "the eye", by the way, we are not doing justice to the problem. It has been authoritatively estimated that eyes have evolved no fewer than forty times, and probably more than sixty times, independently in various parts of the animal kingdom. In some cases these eyes use radically different principles. Nine distinct principles have been recognised among the forty to sixty independently evolved eyes. Dawkins, "Climbing Mount Improbable". p. 127. Tannin
I'm not concerned about whether the term is scientific, I just wanted the name of that argument. the article you linked to points out, however, that the term needs serious disambiguation. --Plasticlax
one more question: i was reading that one explanation for how components of a so-called IC system could evolve by having different functions originally. well, when does that function change? if it was functional, but was then appropriated by the IC system, wouldn't that be a conflict? -
Plasticlax
- I'm not sure about this IC stuff, but this might answer part of your question. In genetics, a gene with multiple functions is refered to as "pleiotropic". Pleiotropism may be rather common...that is an issue that geneticists are investigating as I write. So my point is that one "thing" may have more than one function. A related phenomenon is gene duplication. If a gene is fucntionally pleiotropic, then duplication of that gene can allow each of the duplicates to take on a more specific function. As I understand it, this is rather speculative and some researchers are working on it also. adam
I thought the comments below taken from a metawiki talk page,
Origins of Everything (
http://meta.wikipedia.org/wiki/Origins_of_Everything), would be of interest here and something to consider (although perhaps more relevant to a Controversies re Evolution article). Someone, somewhere sometime once said: "Imagination is more important than knowledge...":
- "I would argue that the simplest explanation of all is that the universe was always here. Alan D"
- "I'd go further and add that it is here to stay and that God is a natural extension of the universe. If mainstream Christianity (or other religions for that matter) were not so invested in its transcendent God (a concept which atheists and many philosophers and scientists recognize as incoherent and rubbish) and settled for a being that was, shall I say, a little more down to earth, religous conflicts with certain scientific theories (like the theory of evolution) would be seemingly moot. Consider that the process of evolution is ongoing...what comes next after humans? Genetically enhanced superhumans? what then?...and after that? Consider a being that over time nature has endowed with such power, knowledge (and hopefully benevolence) that humans might perceive, THAT is God! At that point god or God or supreme being or whatever you want to call it would work as an extension of the universe in creation or evolution whichever you want to call it. B"
- Whilst this all sounds fascinating, this discussion might be best taken to email or meta. We should try to keep talk pages focussed directly on the articles. --203.45.10.22[?]
- I disagree. This viewpoint should be particularly relevant to any "Controversies regarding Evolution" article that will inevitably get spun off from this one. B