Nature correspondence on evolution and ID

This week’s Nature features a nice battle between creationists and evolutionists in the correspondence section.

The debate contains the following parts:

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Dawkins gets the Colbert treatment!

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More debate on consciousness, evolution, and religion

While Thomas is getting his kicks off at the SfN meeting in Atlanta I am toiling away at a number of long overdue papers here in the increasingly cold Denmark. I have several longer blog posts planned, but no time to write them. So, here’s three things to read in the meantime at other venues on the net.

First, John Searle reviews a new book on consciousness by Nicholas Humphrey, Seeing Red, in The New York Review of Books. I have always enjoyed Humphrey’s work, but his new theory on consciousness sounds plain weird (at least as retold by Searle; I haven’t read Humphrey’s book). In Searle’s words:

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Being part of a Brain Parade

Today, a post is up at Meme Therapy on the ethical aspects of techological and scientific advances. It is an interview with a lot of different people with diverse backgrounds. Jose Garcia asks:

We seem to be awash in technological/scientific issues that raise serious ethical questions nowadays. Of these which concern/interest you the most?

You can find my answer down the line, probably the most lengthy of the replies (duh?). Basically, I’m pointing to two major points: 1) the technical advancements that have already occur and will continue to happen, will challenge our current views of humanism, law and morale, volition and other aspects of human affairs. However, 2) how this knowledge is communicated, understood and misunderstood due to everything from bad explanation to religious beliefs, is just as important an issue.

I’d say that today we have a vast majority of academics that accept the Modern Synthesis of the theory of evolution, while a large part of the population as such a) do not believe in evolution; b) think evolution may be correct, but that humans are still “spiritual beings”; c) think that all is right and do not acknowledge that there are any inconsistencies between religion and science; d) think science is “bad” and that it should be discarded altogether.

So where does that put us today? Indeed, if I claimed that I really believed that Santa Claus existed, I’d be able to make use of all the same arguments that those proposing an intelligent design theory rathern than evolutionary theory  of human (and anima) evolution. Yes, I believe that Santa exists, living at the North Pole (or was it Greenland, Norway or Finland, or what?). Just because we can’t see him, doesn’t mean he doesn’t exist, does it? He’s giving you the presents at X-mas, not your parents (just a cover-up). You want me to prove it? No, I don’t believe in science, you can’t measure everything, right? There is more between heaven and earth than that!

-Thomas

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Reviewing evolution

The New York Book Review has a great review by Edward Ziff and Israel Rosenfield of three forthcoming books on evolution. What makes the review so great also is that it describes the development of the idea of evolution, from the feeble beginnings of comparisons between dolphin fins and bird wings, through Darwin’s theory of evolution, to the modern synthesis of evolutionary theory and the linking of genes to evolution, variation and reproduction. It’s a highly recommendable read.

-Thomas

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A Roman Catholic take

Volume 13, issue 5 of the Journal of Clinical Neuroscience contains – in my opinion – a very strange article. It's called "Ethics in medical technologies: The Roman Catholic viewpoint" and is written by Joseph Życiński. I found a wiki-like version of the paper here. The article is not strange because of its topic per se, which is bioethics from a religious point of view. What I find strange is that the article is published in a peer-reviewed scientific journal, and worse, that it is filled with religious dogma that are presented as axiomatic truths. 

Even accepting these strange facts, I find it unacceptable that the article does not discuss critically other approaches such as Gazzaniga's recent book "The ethical brain" (see my blog entry here). With statements such as

According to Christian ethics, we are called upon to treat each and every living member of the human species, including the embryo, as a human person with fundamental rights, the first of which is the right to life.

… I wonder if the insightful criticism of Gazzaniga has ever been read or heard by Życiński. In this way, we can only guess at what the author's opinion is on more scientifically informed viewpoints.

Here is the abstract:

Ethics in medical technologies: The Roman Catholic viewpoint.

Zyciński J

J Clin Neurosci. 2006 May 4;

New medical techniques and novel scientific discoveries bring many basic questions concerning the role of human dignity in medical research as well as in the society of the future. This paper presents the Roman Catholic approach to the use of new technologies, the research of human embryos, the ethical aspects of studies on the human genome. The concept of "human ecology", as proposed by John Paul II, is introduced to reconcile the academic freedom of research with insurmountable ethical barriers which must be recognized to defend human dignity. In critical appraisal of Peter Singer's concept of the quality of life the author points out that it is irrational to try to reduce this quality to the level of biological parameters. Human dignity as well as the sanctity of life express also a quality of life so important for the cultural growth of Homo sapiens. To protect human ecology it is our moral duty to defend human dignity and to recognize the importance of those values that are fundamental in the process of development of the human species.

And speaking of Gazzaniga, I should definitely remember to write the following parts of the book presentation.

-Thomas 

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What makes human brains unique?

In a thorough and very good review in PLoS Genetics, James Sikela writes about the comparative genetics between the chimp and the human genome. From the article:

It has been pointed out that the primary molecular mechanisms underlying genome evolution are 1) single nucleotide polymorphisms, 2) gene/segmental duplications, and 3) genome rearrangement. In addition, a “less-is-more” hypothesis has been proposed that argues loss of genetic material may also be a source of evolutionary change. Given these factors, what are we learning about their respective roles now that we can compare multiple primate genome sequences?

As we have pointed out repeatedly in this blog, the study of genetic influence on the brain is going to change our understanding of what a human is, how and why our thoughts are formed (and restricted) the way they are. This review surely puts the finger on the pulse and notes:

One of the most important findings to emerge from the latest human and primate genome-wide studies is that a fundamental assumption underlying this model has changed: the interspecies genomic changes are numerous and diverse, and, as a result, there appear to be many additional types of genomic mechanisms and features that could also be important to the evolution of lineage-specific traits. Given this new perspective, we now know that the degree of difference between our genome and that of the chimp depends on where, and how comprehensively, we look. The multitude of genomic differences that we now know exists should provide an abundance of fertile genomic ground from which important lineage-specific phenotypes, such as enhanced cognition, could have emerged. 

Here is the abstract:

The jewels of our genome: the search for the genomic changes underlying the evolutionary unique capacities of the human brain

James M. Sikela

The recent publication of the initial sequence and analysis of the chimp genome allows us, for the first time, to compare our genome with that of our closest living evolutionary relative. With more primate genome sequences being pursued, and with other genome-wide, cross-species comparative techniques emerging, we are entering an era in which we will be able to carry out genomic comparisons of unprecedented scope and detail. These studies should yield a bounty of new insights about the genes and genomic features that are unique to our species as well as those that are unique to other primate lineages, and may begin to causally link some of these to lineage-specific phenotypic characteristics. The most intriguing potential of these new approaches will be in the area of evolutionary neurogenomics and in the possibility that the key human lineage–specific (HLS) genomic changes that underlie the evolution of the human brain will be identified. Such new knowledge should provide fresh insights into neuronal development and higher cognitive function and dysfunction, and may possibly uncover biological mechanisms for information storage, analysis, and retrieval never previously seen.

-Thomas 

______________________________

John Hawks has a very good discussion about this article. 

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A Sisyphean task

Dan Dennett is interviewed by Robert Wright about his views on evolution and consciousness. Their views on evolution differ, especially with Wright's contention that evolution is goal-oriented in someway, and that history progresses in a predictable direction and points toward a certain end: a world of increasing human cooperation where greed and hatred have outlived their usefulness. All in the name of evolution — and game theory, that is. IMHO it's a lot of gibberish. Evolution is not teleology. It's a gross misunderstanding of the principles of evolution. I think Dennett does a nice job at pointing this out. Wright is not all ears, though.

On the second topic, consciousness, Wright and Dennett disagree profoundly. I'm not entirely sure whether Wright takes on the job as a Devil's advocate, or if he really means that epiphenomenalism is a logical possibility. I think the latter: Wright seems totally agnostic towards Dennett's thoughts. They simply won't penetrate Wright's mind.

If you listen carefully (with earphones, like me) you'll hear Dennett make a dozen sighs along the talk. I can understand why. It's a Sisyphean task to discuss these topics, and you're bound to run into people with the same scientific agnosticism or even atheism that hinders true progress in our understanding of topics such as evolution and consciousness.

You can find the interview here.

-Thomas 

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ID refuted (once more!)

If you care about these things, there is an exiting paper in yesterday's Science that flat out refutes Michael Behe's argument that certain "irreducible complex" biological organisms couldn't possibly have been formed by evolution. Here's the paper's abstract:

According to Darwinian theory, complexity evolves by a stepwise process of elaboration and optimization under natural selection. Biological systems composed of tightly integrated parts seem to challenge this view, because it is not obvious how any element's function can be selected for unless the partners with which it interacts are already present. Here we demonstrate how an integrated molecular system—the specific functional interaction between the steroid hormone aldosterone and its partner the mineralocorticoid receptor—evolved by a stepwise Darwinian process. Using ancestral gene resurrection, we show that, long before the hormone evolved, the receptor's affinity for aldosterone was present as a structural by-product of its partnership with chemically similar, more ancient ligands. Introducing two amino acid changes into the ancestral sequence recapitulates the evolution of present-day receptor specificity. Our results indicate that tight interactions can evolve by molecular exploitation—recruitment of an older molecule, previously constrained for a different role, into a new functional complex.

While the authors doesn't relate their findings to the ID issue, in an accompanying news perspective Cristoph Adami sets everybody straight:

Although these authors have not directly addressed this controversy in the discussion of their work–because the work itself is intrinsically interesting to biologists–such studies solidly refute all parts of the intelligent design argument. Those "alternate" ideas, unlike the hypotheses investigated in these papers, remain thoroughly untested. Consequently, whatever debate remains must be characterized as purely political.

Naturally, Behe has been quick to argue that the system Bridgham and colleagues discuss is not really "irreducible complex" in his sense. Is he right? Well, Carl Zimmer checked out what Behe earlier wrote in "Darwin's Black Box" and the definition of "irreducible complex" seems to change according to Behe's whim, so I'll let you all make up your own minds!

[Post scriptum. With the publication of the Tiktaalik roseae find in Thursday's Nature it has been a VERY good week for evolution. Why, it almost seems like God doesn't want people "of faith" to win!]
References:

Bridgham, J. et al. (2006): Evolution of hormone-receptor complexity by molecular exploitation. Science 312: 97-101.

– Martin

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