Thursday, July 22, 2010

Transitionial forms re-visted

Over on Topix I have been listening to a creationist try and sound all scientific on transitional fossils. It’s a pretty common argument usually stemming from a misunderstanding of what a transitional fossil really is. The argument usually comes in one of two forms:
  1. There are no transitional fossils
  2. Transitional forms could not survive, so would not be possible under evolution – therefore evolution is obviously false.
  3. While there may have been fossils found that might be transitional, there isn't any evidence linking them to modern forms.

There may be more arguments against transitional fossils, but these seem to be the main themes. Other arguments tend to be more offshoots of these.

Kennie ham is an example of that. His other abortion, Answers in Genesis, tends to lean on the first argument -- although they no longer word it this way. I guess they had problems denying all of the transitional fossils so they sort of claim that it is an argument that should not be used (AiG arguments that should not be used). Now read it carefully, because it really is nothing more than a minor 'adjustment' in the 'there are no transitional fossils argument. Instead of targets transitional fossils as a whole, they are targeting the relationship between species by using the Biblical 'kind'.

Does this sound just a wee bit familiar? How about the whole micro v. macro argument. You know the one where anti-evolutionists quit arguing that evolution was impossible and now argue that speciation is impossible. Well actually they claim that speciation has not been proven. This is nothing more than another transitory face-saving gesture. Can't deny, evolve the argument into something else. Well at least they are consistent.

"We find variant transitional fossils for animals within the same kind—horse to a horse for example but that is expected in a biblical worldview."
Rather than dwelling more on kennie's delusions, let's talk about transitional fossils. What is a transitional fossil, also known as a transitional form. Oh, and biology also calls them 'intermediate' forms. I looked up ‘transitional fossil’ in Wikipedia ( and saw that they defined it as simply the remains, such as a fossil, that exhibit an evolutionary transition. In other words it displays certain characteristics from earlier ancestors and contain, usually in a more primitive form, the attributes of species that come later. Here is a pretty impressive list of some of the transitional fossils that have been found: Wikipedia also has a nice long list at

So how do some groups continue to make such a ridiculous claim? By redefining what a transitional form is. You have no idea how many times someone mentions the cat-dog, or used a nonsense phrase like ‘true transitional form’. What they are doing is changing the goal posts. They cannot argue against the evidence of the hundreds, even thousands, of transitional fossils, so they change the definition and claim that the fossils are not ‘really’ transitional mainly because they don't look like something out of the late-late show. AiG does this by inserting the word ‘kind’ and ignoring the evolutionary evidence. It goes something like this : Within the Horse kind you have horses, zebras, and donkeys. In the Cat kind you have lions and tigers. In the Bear kind you have polar, grizzly, and brown bears. Now let us not forget that kennie ham is a biblical literalist . . . and yet this concept of 'kind' for horses, bears, and cats is an invention of the 'mind' of kennie ham – thereby immediately suspect. He uses this idea to explain things like mules, hinneys, zorses, polar-brown bears, ligers and tigons. In other words, hybrid species. He completely ignores the evolutionary studies that show why these hybrids can exist and hybrids of species that are further away from their evolutionary relationship cleft point do not exist. But that’s a stock in trade, ignoring the evidence.

So argument number one is bogus, there have been transitional forms, there will continue to be transitional forms – in fact we are all transitional forms from the past and into the future. The ones we identify as 'transitional' are the ones that more clearly demonstrate the past and future. Who knows some future biologist may list homo sapien as a transitional form. There would be a hit to kennie's ego! Of course none of his ideas are supported by the evidence, only a denial of the evidence and a fanciful tale of how he sees the world. So much for the Biblical Literalist when he has to invent explanations to support his viewpoint..

Well since that denial tactic doesn't work at all, some creationists have started a more targeted argument. They have taken the idea of transitional forms and claimed that they would not be workable or survive in the real world. Now they point to the fact that the transitional forms that we have found in fossils so obviously the forms didn’t survive. Not true! Many of the forms exists for even longer than homo sapiens have been around. They were here and now they are not, but many were around for millions of years. We have yet to hit our first millennia let alone 10, or 100.

Here is the problem for creationists, the fossil record is not the only support for the transitional forms. There are the comparative studies of modern organisms that draw the parallels between species, past and present. This is easily illustrated by the adaptive radiation of the forelimb of mammals. All conform to the basic pentadactyl pattern but are modified for different usages. Or you can look at the pelvic relationship between dinosaurs and birds. Geography also plays a part in supporting the idea of transitional fossils. As we look at both ancestral forms and modern forms you have to look at the geography and where they are located! As you go back in the fossil record, geology also supports transitional forms because we are not just looking at the fossil, but the geological strata they are found in. This indicates the timeline for the changes. It’s when you take ALL the evidence into account you can see the picture that folks like kennie ham are doing their best to ignore. They challenge some of the pieces, ignore the others, and never look at the entirety of the evidence.

So the second argument is also bogus, so where is a creationist to go? Well recently another whine, represented by the third argument, that the relationship between forms is not supported, that many of the forms are not in a direct relationship with modern forms, has been popping up, the confusion between a transitional form and an ancestral form. I was tempted to write this one up, but another poster on Topix beat me to it. Here is Feklahr’s post: (

Regarding Transitional Fossils

I thought it would be wise to address some of the confusion surrounding the term "Transitional Fossil".

First, some links:

Second, a paragraph from the second link regarding transitionals:

Transitional vs ancestral

"A source of confusion is the concept that a transitional form between two different taxinomic group must be directly ancestral to one or both groups. This was exacerbated by the fact that one of the goals of evolutionary taxonomy was the attempt to identify taxa that were ancestral to other taxa. However, it is almost impossible to be sure that any form represented in the record is actually a direct ancestor of any other. In fact because evolution is a branching process that produces a complex bush pattern of related species rather than a linear process that produces a ladder like progression, and the incompleteness the fossil record, it is unlikely that any particular form represented in the fossil record is a direct ancestor of any other. Cladistics deemphasized the concept of one taxonmic group being an ancestor of another, and instead emphasizes the concept of identifying sister taxa that share a common ancestor with one another more recently than they do with other groups. There are a few exceptional cases, such as some marine plankton micro-fossils, where the fossil record is complete enough to suggest with confidence that certain fossils represent a population that was actually ancestral to another later population, but in general transitional fossils are considered to have features that illustrate the transitional anatomical features of actual common ancestors of different taxa rather than to be actual ancestors."

In closing:

What I am trying to demonstrate here is the misnomer surrounding transitional fossils. If we use the Archeopteryx example, it is listed as a transitional because it exhibits features of both dinosaurs and birds. It is not posited that it is the "middle form" in the transition of dinosaurs to the modern bird features. In other words, it is not an "ancestral" form to the modern bird, simply a species that exhibits both dinosaur like and bird like traits during a geological period between the proliferate life of dinosaurs and the proliferation of bird life.
So the bottom line on these particular arguments are more mischaracterizations of evolution. Evolution is not a straight line process and just because a fossil is identified as transitional doesn't require that it be in a direct-line relationship with a modern form. When cladistics traces something like the evolutionary line of the modern horse, they could be wrong on some of the details -- but what they are showing is the best evidence based on current knowledge that we have. A new fossil might change our understanding -- that's how science works. What we end up with is not just a different explanation to some degree, but a better explanation, a more complete explanation! Things are supported, not proven, and new knowledge can change the support. Nice job Feklahr, thanks!

So not only do transitional forms exist, but there are thousands of them. There is no 'missing link', but there are many links between different species. We are engaged in finding them and the work continues. Each new discovery tends to send the creationists scrambling for some new rationalization. It certainly is fun to watch. Just like the Discovery Institute tried about Tiktaalik in an post by that simplistic mouthpiece little casey luskin titled "Tiktaalik blown out of the water by earlier terapod fossils". See what I mean, rationalizations!


  1. So not only do transitional forms exist, but there are thousands of them. There is no 'missing link', but there are many links between different species. We are engaged in finding them and the work continues.

    Don't you ever wonder why your various mythologies of Progress all seem to so seamlessly blur together? It is assumed that evolution, whatever it is, is true. Indeed, it is the equivalent of knowledge itself in the minds of many. This is the paradigm by which science is defined and therefore it is always being inevitably verified and never falsified. Every single organism that has been observed supports evolution, whatever it is. And even if one supposedly did not that would only show how evolution would inevitably be found to be true in the future thanks to progress, i.e. evolution. Indeed, at a wider level some use the same term to describe every single change that has or ever will happen in the entire Cosmos. Given that, it's little wonder that evolution seems so overwhelming to some.

    But as far as every single fossil which has been found supporting evolution, whatever it is, why is that surprising? After all, as you go on to point out every single organism is transitional just as all your mythologies of Progress merge seamlessly one into the other.

    On the other hand, for those interested in more than the unfalsifiable hypothetical goo typical to hypotheses of evolution there are some definitions and specifications which are not merely figments of our imaginations. They are the sort of definitions and observations which may be missed by those blinded by the Darwinian urge to merge.

    Stasis is data.

    So if stasis could not be explained away as missing information, how could gradualism face this most prominent signal from the fossil record? The most negative of all strategies-a quite unconscious conspiracy of silence-dictated the canonical response of paleontologists to their observations of stasis. Again, a “culprit” may be identified in the ineluctable embedding of observation within theory. Facts have no independent existence in science, or in any human endeavor; theories grant differing weights, values, and descriptions, even to the most empirical and undeniable of observations. Darwin’s expectations defined evolution as gradual change. Generations of paleontologists learned to equate the potential documentation of evolution with the discovery of insensible intermediacy in a sequence of fossils. In this context, stasis can only record sorrow and disappointment.
    Paleontologists therefore came to view stasis as just another failure to document evolution. Stasis existed in overwhelming abundance, as every paleontologist knew. But this primary signal of the fossil record, defined as an absence of data for evolution, only highlighted our frustration-and certainly did not represent anything worth publishing. Paleontology therefore fell into a literally absurd vicious circle. No one ventured to document or quantify-indeed, hardly anyone even bothered to mention or publish at all-the most common pattern in the fossil record: the stasis of most morpho-species throughout all their geological duration.
    (The Structure of Evolutionary Theory (Harvard College) by Stephen Jay Gould :759-760)

    But if everything is transitional then I guess that stasis is an illusion, not data, correct? The interesting thing about the notion that everything is changing is that the more it changes the more it seems the same.

  2. I think you have your history mixed up. Fossils have been discovered for a long time, well before Darwin and the theory of evolution. The idea of the relationship between modern organisms and the evidence left from organisms in the past led to many questions, some dating back to Plato and Aristotle.

    The Theory of Evoltuion, particularly Natural Selection in this case, was the first mechanism that offered an explanation that made sense based on that evidence. It has so far withstood 150 years of study and experimentation -- not because it is an assumption of truth prior to a discovery, but because no other explanation fits the evidence. Other scientists would love to find a discovery that would knock back evolution -- it would be a career maker!!

    You want to show evolution is false, it really wouldn't take much. Find one rabbit skeleton in the stomach skeleton of a disonsaur. That would do it. Have we found the fossilized stomach contents in dinosaurs? yes we have -- but no rabbits or any organism that evolved at a later date.

    I would recommend a better understanding of the history of evolutionary theory and even a better understanding of how fossils and transitional forms support it -- including the methodology used. It's not a bunch of wild guesses.

    As for every organism being a transitional form . . . when you bother to think about it, it's true. Life on the planet has changed greatly over a very long period of time. There is NO evidence to suggest that the future will not bring more changes. Will there be homo sapiens in a million years? I don't know for sure, but the evidence says probably not.

    What you are quoting is part of the support for "Theory of Punctuated Equilibrium" which is part of evolutionary theory. It shows that there is evidnece of the gradualism discussed by Darwin, but there is also evidnece of more rapid evolutionary change. The Italian Wall Lizard is an example. A small population was transported to a Croatian Isalnd and have undergone dramatic changes in a few decades. But the source of those transported lizards have not changed in the same time period. Evironment is the key to both.