Monday, April 22, 2013

What Darwin Didn't Know- Ch 1 -The Scope of Challenges - Part 5: The Problem of Intermediates - Pt 3

Book Cover: What Darwin Didn't Know
I dove into Geoffrey Simmons' "What Darwin Didn't Know" (2004), to evaluate an anti-evolution book.

I'm maintaining an index of my responses here.

Today's Chapter - 1: The Scope of Challenges - Part 5:  The Problem of Intermediates - Pt 3

First, I actually need to complete the previous post. I accidentally skipped the last two sentences, in regards to our supposed ancestry from the other primates:
And where did the tail go? The entire appendage just dropped off.
Keep in mind, along with the other points I had made about our bipedal plains-dwelling scenario, and what would have affected us, like losing a fur coat, trying to run around with a tail would also be cumbersome - so it's to be expected that it'd fade away.

Think of other bipeds - birds, or even some dinosaurs. At most, the tails were for balance, but that's because their torsos protruded forward, while we're mostly vertical, and that mechanism no longer is practical.

Further, look at the chimpanzees - our closest wondrous cousins who we share a common ancestry about 6-8 million years ago. They don't have tails either. Whatever the history of the loss of our tails (which didn't disappear - it became vestigial), it predates our common ancestry with chimpanzees. Does that commonality not support common ancestry?

It'd also be useful to note that we still basically have the tail gene, which can be expressed, similar to the "werewolf syndrome" (link to article about human tail atavism).

In both examples, these are demonstrations that these attributes were part of our past. In the creationist model, what would be the point of disabled/non-expressed genes? Were we hairy, with tails, in the Garden of Eden, and our fall from grace turned off those genes?

Lastly, "it just dropped off"? Citation needed. What does he even mean?

As usual, he has numerous vague unsupported statements to make - some that he seems to conjure out of thin air.

Continuing to the next part, he quotes Darwin having concerns about missing intermediate fossils.

[Darwin quote:] The number of intermediate varieties which have formerly existed on the Earth must be enormous. Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain: and this, perhaps, is the most obvious and gravest objection which can be urged against my theory.
It would be weird if that was the case, however, Simmons can stand alongside Darwin here in being corrected. I've covered a number of these things, but let's rehash it a bit, shall we?

We do have a sizable list of "intermediate varieties"

Link to handy list of transitional fossils... again.

Punctuated Equilibrium

Punctuated Equilibrium (link to reference), while still debated, would cause an already rare process (fossilization) to under-represent transitional forms.

Big problem of definitions

I pointed out, when Simmons first started talking about the supposed missing transitional fossils, that he omitted providing the definition he was working under.

Firstly, most modern-day dogs evolved from wolf-dog common ancestors, as humans artificially selected them into the myriad of species/subs-species we have today. If we were to examine those common ancestors, would we identify them as "intermediate"? I don't think Simmons would, without the information about the wolf/dog heritage... but it's possible there's another definition here.

Secondly, depending on the definition we're using, penguins, walruses, mudskippers, seals, etc, would all be intermediate forms. We'd be swamped by modern-day intermediate forms, left and right. I take it, though, that he's not recognizing those under his unstated, mysterious definition. The definition I believe "transitional form" to be, would be an intermediate form between two major stable forms - for instance, between a complete land-walker and a complete water-swimmer. Mudskippers and walruses would qualify. There doesn't have to be anything magical about it.

Thirdly, we may be drastically misunderstanding what the intermediate forms would be. Consider a possible evolutionary path between a mouse-like form (form A), and a cat-like form (form B). People like Simmons are probably operating under the assumption that the "true" intermediate form (let's say midway through the lineage) would be an exact average. For instance, the size of the intermediate form would be halfway between the two - (if the mouse-like form is 10g in mass, and the end cat-like form is 1kg in mass, the intermediate form would be 505g).

Evolution tends to produce wholly functional forms at every stage (no "half-eyes", or "half-legs", depending on what those mean). It could be that the intermediate form between A and B is actually bigger than either. Why not? If we cast aside these preconceived notions about what intermediate forms are, and trace an actual real evolutionary path from ancient ancestor to descendant, we may find that the form varied wildly, at times being unlike both the starting or ending points.

...and the problem of the discrepancy between what we'd expect to find, and what evolution would produce, isn't a problem with evolution. It's a problem with the theory that describes it - our understanding of the phenomenon.

It could be that the fossil record is riddled with intermediate forms, but we aren't recognizing them, due to this misconception.

It's a good question that warrants discussion and investigation. Simmons doesn't bother to even provide a definition, let alone explore the topic with any kind of nuance. His only goal here is to take a jab at the theory, whether it's based on a salient coherent understanding or not, and move along to the next attack.

We already know, from the other branches of independent cross-confirming lines of evidence, that common ancestry is true. Even if we were to find no transitional fossils - it would be strange, but the theory would still have considerable, and arguably more significant, positively supportive evidence from the other fields. We'd certainly investigate the lack of transitional fossils, which would weaken the theory until it's figured out, but would hardly spell the end of the theory. That would only come when that particular mystery is solved - and not merely because we don't currently know why this particular oddity, to an already solidly demonstrated phenomenon, is happening.


You won't argue with me, if I decide to put this "problem of missing intermediate fossils" to rest, will you? I'd rather not address the same tired old arguments over and over. For now on, if it comes up again, unless there's something new to address, I'll simply link to this, and potentially other previous posts I've made on the topic.

We have an extensive list of transitional fossils - growing larger by the year.

This argument is so dead, it's starting to fossilize.

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