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According to Darwin, the absence of intermediate fossil forms “is the most obvious and gravest objection which can be urged against my theory.” What new fossil finds, if any, have occurred since Darwin wrote these words nearly 150 years ago? Do they overturn Darwin’s bleak assessment of evolutionary theory? If the absence of intermediate fossil forms holds as much today as it did back then, why should anyone accept evolution?

This question is taken from Five Questions Evolutionists Would Rather Dodge By William A. Dembski, I have asked it here so the rationalist, scientific and skeptical communities can collectively provide well researched and logically sound answers.

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I guess I could explain, but certainly Richard Dawkins can do it better. –  rsenna Feb 25 '11 at 13:22
You're getting good answers, but there's a certain "preaching to the choir" flavor to this whole exchange. On the one hand, evolution-doubters tend to frame their positions in closed-minded ways. OTOH, enthusiasts tend to be a little defensive. Certainly votes of scientists is no way to argue issues (though that's not what's happening here). I have yet to see a way to discuss this issue rationally and respectfully with doubters. –  Mike Dunlavey Mar 14 '11 at 20:30
@Rudie: Having read Origin of Species some years back, I think Darwin was just trying to be scientifically honest. No theory is ever 100.0000% proven by evidence. In fact, one desirable property of a scientific theory is falsifiability - the logical possibility that there could be some evidence to contradict it. If there were no such possibility, then there's really no sense in testing it, and it's really not saying anything. That's a point that Intelligent Design adherents often don't get. –  Mike Dunlavey Mar 14 '11 at 20:40
Not sure if anyone's said this yet but the term "transitional fossils" is such a bunk phrase. All fossils are transitional. –  billynomates Jul 25 '11 at 8:30
This question is outdated; the evolution debate ended when genetics was discovered. We don't need to fondle fossils to support evolution any more. We hit the mother lode: phylogenetics. –  Emre Aug 2 '11 at 5:44
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4 Answers

up vote 62 down vote accepted

The absence doesn't hold up. In fact there are tons of intermediate fossils. Good examples are the evolution of birds and humans. Early birds are more or less just dinosaurs with wings (and we now know that many dinosaurs had primitive feathers as well). And with this you can see a clear path from dinosaurs, to bird-like dinosaurs with feathers, to early dinosaur-like birds to birds, so therefore the bird-like dinosaurs and dinosaur-like birds are in fact intermediate fossil forms between dinosaurs and birds.

In human evolution we can clearly see that australopithecines, being upright-walking apes, are intermediate between apes and humans, and that early homo in turn is intermediate between australopithecines and homo sapiens.

The argument is then sometimes said that they are not intermediate forms between species. But that argument doesn't hold up because the line between species isn't necessarily sharp. It's an arbitrary grouping we humans do. You can't have an intermediate form between two species, because we will decide which species it belongs to. But nature makes no such distinctions.

Normally the animals within one species can interbreed, but no interbreeding can be done between species. But there are species of birds where birds from the eastern part of the population will not mate with birds from the western part of the population. But yet there is never a clean break in between.

And everyone knows Coyotes and Gray Wolves are different species, right? But Gray Wolves can (and sometimes do) mate with red wolves, that can (and sometimes do) mate with Coyotes. (In fact there is some speculation that the Red Wolf itself is a mix between Gray Wolf and Coyote. I don't know if any conclusion has been drawn on that).

In evolution it is even more self-evident that there is no clean break between species, and one species slowly evolves from another. So if you find an intermediary form, i.e. something you can't clearly specify as species A or species B, you tend to give it a species of it's own (with a significant expansion of species in Homo during the last decades as a result).

So the grouping of individuals into species are often arbitrary, and as long as we always stick every individual into one species, we won't get intermediary forms between species. But it's clear that different species are intermediary forms of other species, so the evidence is there in the fossil record, with no doubt.

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+1 excellent discussion on inter-species intermediaries –  David Hedlund Feb 25 '11 at 14:08
(-1) No sources, and all the "clearly" and "obviously" words make the lack that much worse. But I can't vote down yet anyway. –  mmyers Mar 25 '11 at 15:34
@LennartRegebro, I can say anything is obvious without sources. I agree with you, but that does not change the fact that an opinion without sources is an opinion. It is as much not science as faith. Trusting you without source actually is faith. –  Kortuk Mar 25 '11 at 22:43
@Kortuk: I've never claimed to be trustworthy. :-) I did not attempt to prove anything, I attempted to explain. I don't want you to trust me, I want you to think for yourself and understand. More sources would not help as you should not trust these sources either, so trusting me with sources would be just as much faith as trusting me without sources. So don't do that. Always think for yourself! –  Lennart Regebro Mar 26 '11 at 7:47
@Kortuk: I'm sorry I don't think the comment field on a SE site it the right place to explain how science works. But there is no faith in science whatsoever and you should not accept peer-reviewed articles on faith either. –  Lennart Regebro Mar 26 '11 at 18:17
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In the past 150 years, we have made heaps and heaps of new fossil finds. If the fossil record of today had been available 150 years ago, I dare say there would not have been much for Chuck to figure out in the first place, because everyone would immediately see what's going on.

This is definitely not a question that evolutionists would rather dodge, but it is, perhaps, one that we've grown quite weary of.

For what it's worth, however:

  • The fossil record is rich enough to be evidence of evolution even if we had no other evidence for it at all

  • We do, in fact, have other evidence and that would in turn be convincing enough even if there was no fossil record at all! Evidence is abundant.

  • While Darwin was indeed concerned about the, to his mind, poor fossil record of his time, he did spend an entire chapter of Origin on explaining the extremely rare circumstances under which fossilization occurs, giving an excellent account for why we aren't finding more of it. It is the most boring chapter of an otherwise excellent read, and it is also the chapter since rendered most redundant, as his concerns are no longer very valid.

  • Speciation occurs when members of the same species are suddenly isolated from one another for a substantial period of time. This is one of the driving mechanisms behind punctuated equilibrium. For this reason among several others (such as varying selection pressure), evolution is not constant linear momentum in one direction. A completely linear progression in the fossil records without "gaps" whatsoever would be difficult to explain. Even evolutionists expects some gap.

  • The fossil record would be one among several splendid places to easily falsify the theory of evolution. No single falsifying fossil has yet been found, though. I'd argue it's convincing evidence on its own, that the theory has effortlessly withstood 150 years of deliberate attempts to falsify it.

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++ for "Chuck". –  Mike Dunlavey Mar 17 '11 at 20:36
Hi @David, we are trying to clean up the site a bit, can you add references to this (old) answer? –  Sklivvz Jul 24 '11 at 18:20
Nice one, @MSalter. –  Oddthinking Aug 2 '11 at 8:52
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The Dembski article is full of straw-man arguments, such as "evolution has become an ideology".

Since when?

It's a theory. It offers an explanation for things, that's all. It's testable. Evidence could contradict it, but hasn't (yet).

Look at other theories:

  • Newtonian physics. It explained things pretty well, but after a while some evidence comes along to contradict it. Did that make it flat-out wrong? Of course not. That only meant a more refined theory was needed. It has since been superceded by relativistic physics, and then by quantum physics. Theories build on each other.

  • The Copernican theory that the earth revolves around the sun was controversial in it's day, because a class of people claimed it contradicted scripture. So was it testable? At the time, not really. It just offered another, possibly simpler, explanation for things that could be seen. Later it, too, could be refined or replaced, which did not make it wrong.

The thing about theories is, they are not a matter of "belief" or "ideology". They are just mental frameworks for trying to understand things and fill in the gaps of what we see. Then if in our curiosity about the world around us, we see something that doesn't quite agree with the theory, it may be time to refine it or find something better, that's all.

Aside: If this question is really about "Intelligent Design" (as I suspect it is), I would say "Well, why not?" There's nothing to prove there isn't an intelligent designer behind nature, or several of them, or a stupid one, or a childish one just having a little nasty fun before lunch. When there's evidence to support such a thing, great. Having open scientific questions is not evidence for them.

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Not to mention the Dembski article's entire foundation for proving creationism is a false dilemma fallacy. "Evolution is incorrect, creationism is therefore correct." From The Nizkor Project: A False Dilemma is a fallacy in which a person uses the following pattern of "reasoning": 1. Either claim X is true or claim Y is true (when X and Y could both be false). 2. Claim Y is false. 3. Therefore claim X is true. ** While they never explicitly claim that evolution and creationism are the only two possibilities, it's implicit every concluding statement he makes. –  Alain Mar 25 '11 at 17:11
Hi @Mike, we are trying to clean up the site a bit, can you add references to this (old) answer? –  Sklivvz Jul 24 '11 at 18:21
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The theory of evolution offers the best explanation for how organisms have evolved over time. It hasn't been disproven yet.

Rather than trying to 'mix and match' fossil records, we can utilize DNA to track what species branched off of the family tree at what point in time by the mutations present in the DNA. Certain DNA chains are known to mutate at a given rate - by following the number of mutations, you can see where they 'branched off' on their own, so to speak.

Sometimes the DNA classification upholds the fossil record (such as the evolution of the horse), other times, it leads us to a new classification of an organism (as in, it's more closely related to the hippo than the elephant).

Source: Campbell & Reece, 2005. Biology, 7th Edition. Pearson Education, Inc. San Francisco, CA. 1231 pages.

Science is fluid - it's ever learning and ever changing, based on the knowledge learned.

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Excellent first sentence, especially highlighting "it hasn't been disproven yet" being a (the?) cornerstone of the scientific method, namely falsifiability. I might consider changing the last sentence from "based on the knowledge learned" to "based on observation and experiment", but that's being awful nitpicky of me. :) –  Brian M. Hunt May 2 '13 at 20:23
The species problem is in a sense worse then when Darwin wrote "I was much struck how entirely vague and arbitrary is the distinction between species and varieties" in On the Origin of Species, and DNA cannot draw a line. Mendelian genetics forced significant changes to Darwinian theory to bring it into the modern synthesis but, despite this, horizontal gene-transfer challenges the Darwinian tree of life and common descent. So the theory of evolution has reached a stage where it will never be disproved, since it is flexible enough to be adapted to new scientific discoveries. –  Henry Mar 28 at 13:56
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protected by Sklivvz May 5 '13 at 12:12

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