You have the brains of a worm…

| 16 Comments

Well, not exactly… But the following press release allows us to explore a common confusion amongst ID proponents, in addition to providing more compelling evidence supporting common descent.

The origin of the brain lies in a worm: Researchers discover that the centralised nervous system of vertebrates is much older than expected

First of all, an “ancient” evolutionary prediction

The findings provide strong evidence for a theory that was first put forward by zoologist Anton Dohrn in 1875. It states that vertebrate and annelid CNS are of common descent and vertebrates have turned themselves upside down throughout the course of evolution.

So how come UcD ‘contributor’ DaveScot considers the findings an argument from incredulity? And what are ID’s explanations and or predictions?

Comparing the molecular fingerpint of Platynereis nerve cells with what is known about vertebrates revealed surprising similarities.

“Our findings were overwhelming,” says Alexandru Denes, who carried out the research in Arendt’s lab. “The molecular anatomy of the developing CNS turned out to be virtually the same in vertebrates and Platynereis. Corresponding regions give rise to neuron types with similar molecular fingerprints and these neurons also go on to form the same neural structures in annelid worm and vertebrate.”

“Such a complex arrangement could not have been invented twice throughout evolution, it must be the same system,” adds Gáspár Jékely, a researcher from Arendt’s lab, who contributed essentially to the study. “It looks like Platynereis and vertebrates have inherited the organisation of their CNS from their remote common ancestors.”

The article itself Molecular Architecture of Annelid Nerve Cord Supports Common Origin of Nervous System Centralization in Bilateria was published in Cell, Vol 129, 277-288, 20 April 2007

So let’s compare science’s approach to ID’s hypothetical approach to resolving these data.

ID: We do not know how these similarities may have arisen naturally, thus based on the improbabilities of known pathways, we conclude ‘designed’. End of story

Science:

To understand the long and rich history of science we need to go back to 1875 when Anton Dohrn made its predictions in a monograph titled “Der Ursprung der Wirbelthiere und das Princip des Functionswechsels” (The origin of vertebrates and the principle of succession of functions.)

Correspondence, Karl Ernst Von Baer (1792-1876), Anton Dohrn (1840-1909) By Groeben, Christiane, Karl Ernst “von” Baer, Anton Dohrn, Jane Marion Oppenheimer Translated by Christiane Groeben, Jane M. Oppenheimer Published 1993 DIANE p.22

Dohrn’s hypothesis about the relationship of annelids and other bilaterians was not well received initially by von Baer but it seems that over time, additional data has allowed us to delve deeper into the origin of these two body plans.

However, again, this was not an argument based on ignorance but rather an argument based on the assumption of common descent and the amount of similarities between the central nervous system of annelids

Our data indicate that this mediolateral architecture was present in the last common bilaterian ancestor and thus support a common origin of nervous system centralization in Bilateria.

Since data from fossils was unable to resolve these origins, the researchers compared a present day annelid with a present day fly.

Given the obvious paucity of information from the fossil record, the main strategy to elucidate CNS evolution is to compare nervous system development in extant forms. Our comparative study of mediolateral neural patterning and neuron-type distribution in the developing trunk CNS of the annelid Platynereis revealed an unexpected degree of similarity to the mediolateral architecture of the developing vertebrate neural tube

(See also figure 7 in the paper)

So no argument from ignorance, no argument from incredulity but an argument based on a solid foundation of science. That some ID proponents are confused about science comes to no surprise however.

PS: Figure 7

16 Comments

Since data from fossils was unable to resolve these origins, the researchers compared a present day annelid with a present day fly.

Um, shouldnt that be “.…compared a present day annelid with a present day vertebrate.

Since data from fossils was unable to resolve these origins, the researchers compared a present day annelid with a present day fly.

Um, shouldnt that be “.…compared a present day annelid with a present day vertebrate.” ?

ID-ers idea of an argument from incredulity:

“Such a complex arrangement could not have been invented twice throughout evolution, it must be the same system”

ID-ers idea of an argument from logic:

“Such a complex arrangement could not have been invented once through evolution, it must have been designed”

The missing step

This overall similarity surpasses that documented previously for vertebrate and fly and indicates that a CNS already existed in Urbilateria.

I have added a link to the image for figure 7 in the paper. Btw the paper’s full text is freely available online.

I wish we could just tell the IDers that they are wasting our time, but that would be ‘arrogant’.

“And what are ID’s explanations and or predictions?”

That’s easy. Isn’t it obvious? Brain tumors in earthworms are responsible for making the brain better. Can’t wait to see the paper come out in an ID journal.

Amazing stuff. Just another example of how puny Creationism and Intelligent Design are in respect to the full brunt of evolutionary science.

On Telic Thoughts Mike Gene seems to see evidence of front loading in all this. Which of course is nothing different from common descent but with a certain ‘feel good’ to it, after all as Mike seems to have uncovered faith and science need not be at odds, just move the moment of ‘design’ far enough back in time and our ignorance will allow us to safely accept the concept of ‘design’.

However, front loading has no direct relevance to design other than that it is compatible with it.

Wesley Elsberry was the first to predict this retreat of ID into front loading.

Such a complex arrangement could not have been invented twice throughout evolution, it must be the same system

Davescot responded: So how is it that NDE proponents can use an argument from personal incredulity and get away with it while the same argument when employed by an ID proponent is dismissed as a logical fallacy? A double standard is how.

Wrong. The original statement is not an argument from personal incredulity. It is a recognition of the extremely low probability of two systems independently taking the same evolutionary course. It’s akin to flipping two coins 1,000 times and getting the exact same sequence for both. The AFPI is a gut evaluation aimed at a single sequence of events, which claims it cannot have occurred. It is often accompanied by statistically interesting claims, but almost never good solid calculations of probabilities.

A wonderful “just so” tale!

There we have it, the sum and substance of ID’s contribution to science. “nah nah nah I’m not listening!!!!”

PvM wrote: “On Telic Thoughts Mike Gene seems to see evidence of front loading in all this.”

He’s seen it in many other instances, too, but only after the fact. Front loading makes clear predictions, and Mike runs away from them.

“Which of course is nothing different from common descent but with a certain ‘feel good’ to it, after all as Mike seems to have uncovered faith and science need not be at odds, just move the moment of ‘design’ far enough back in time and our ignorance will allow us to safely accept the concept of ‘design’.”

But this is where you make a huge mistake in framing, Pim. It’s not that ID isn’t science because there aren’t any predictions (as you say), it’s that ID proponents refuse to make and test any predictions. There’s a huge difference.

Think about persuading a person of faith: 1) Ethically, it’s a scientist’s duty to attempt to falsify her own hypothesis. 2) For us real scientists, when we have more confidence in a hypothesis, we are very eager to attempt to falsify it, because we have FAITH. 3) ID proponents have yet to produce a single datum from a test of an ID hypothesis. 4) Therefore, they are not real scientists and/or they have no real faith in their hypotheses. They are intellectual cowards.

Isn’t that better than falsely claiming that ID can’t make predictions? Even if it was true, the ID proponent can just make a pseudoprediction to rebut you, and you lose in the eyes of a lay person. It’s also better than ranting about peer review; given that peer review is the most corruptible part of science, it was inevitable that IDers could weasel in papers in bottom-tier peer-reviewed journals.

“However, front loading has no direct relevance to design other than that it is compatible with it.”

If we hypothesize when front loading happened, it generates readily testable predictions–we will find nonfunctional genes in the front-loaded organisms. For instance, Behe (who hypothesizes front loading) claims that the V(D)J recombination system is IC and therefore could not have evolved. That makes a clear prediction: if we look at the homologous recombinase in sea urchins, who don’t have an adaptive immune system, it won’t have a function. If it does, it wasn’t front-loaded.

I’m wondering how long it will be before the ID quote miners delve into “Such a complex arrangement could not have been invented twice throughout evolution, it must be the same system” and produce ‘ Some scientists admitted ‘Such a complex arrangement could not have been invented … through… evolution …’ ‘.

Overton,

I can make a tire without using rubber. Therefore rubber does not exist.

Re “Evolution explains all existence.”

Evolution explains the observed interrelatedness of known lifeforms, and observed changes in lifeforms over multiple generations. It’s accuracy does not depend on having an explanation for the existence of matter, energy, and space-time, or even planets and stars.

Overton Wrote:

A wonderful “just so” tale!

No, yet another confirmation of the vertebrate “flip”, established in several other works.

Smokey Wrote:

It’s not that ID isn’t science because there aren’t any predictions (as you say), it’s that ID proponents refuse to make and test any predictions.

I sympathize with the issue of framing, but it is really hard to envision any predictions of ID. Possibly they could say that the designer is perfect (no unused trait or DNA) or frontloaded (DNA contains all possible traits). That is about it, I think, without going into how natural processes such as evolution is the ‘designer’.

A working compromise frame could be to point out that IDiots refuse to describe their designer, as you do, without elaborating on the eventual possibility.

IC doesn’t follow from ID, it is merely compatible with it. It is also, in all known forms, compatible and predicted by evolution. The added assumption of “could not have evolved” is an argument from ignorance.

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This page contains a single entry by PvM published on April 22, 2007 1:12 PM.

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