Given the likelihood that the ctenophore lineage is the deepest branch among metazoans, let's have a closer look at the toolkit contained by these creatures to determine if the basic theme of front-loading evolution continues to hold up.

Consider two classes of transcription factors that are known to play crucial roles in metazoan development: the T-box proteins and the SOX proteins. Both factors activate a variety of genes involved in body plan formation, organ formation and cell specification. And as we might expect from a front-loading perspective, PCR analyses have retrieved a rather complex array of both transcription factors from the comb jellies.

Consider the conclusions from two different studies:

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Awhile back I offered what I considered to be an inductive argument for ID here:

http://telicthoughts.com/inductive-argument-for-id/#more-1609

Even though it wasn't an argument from ignorance, it was criticised as being such. Recently, MiKe Gene has brought up the topic of proteins here:

http://telicthoughts.com/an-amazing-design-material/

What I consider to be interesting is that we can make an inductive argument for ID in regards to proteins. First, let's review the form of an inductive argument:

(1) All known Bs are Cs.
(2) X is B.
(3) Therefore X is probably C.

There is an inherent weakness in any inductive argument: How do we know our sample of Bs is large enough to allow a valid inference to C? And the answer is: We never know. That doesn't stop us from using inductive arguments in order to draw probabilistic conclusions. What it means is that we should realize the weakness, and be cautious about our conclusions. With that in mind, here is the following argument: Read the rest of this entry »

I myself don't follow the mind-brain debates closely, but I do know there are several readers of our blog who are quite interested in that topic. If you are one of them, you will probably be interested in an article in the recent issue of BioEssays by Alfred Gierer (from the Max Planck Institute for Developmental Biology) entitled "Brain, mind and limitations of a scientific theory of human consciousness" (BioEssays 2008; 30:499"“505.) Here is the abstract:

In biological terms, human consciousness appears as a feature associated with the functioning of the human brain. The corresponding activities of the neural network occur strictly in accord with physical laws; however, this fact does not necessarily imply that there can be a comprehensive scientific theory of consciousness, despite all the progress in neurobiology, neuropsychology and neurocomputation. Predictions of the extent to which such a theory may become possible vary widely in the scientific community. There are basic reasons"”not only practical but also epistemological"”why the brain"“mind relation may never be fully "˜"˜decodable" by general finite procedures. In particular self-referential features of consciousness, such as self-representations involved in strategic thought and dispositions, may not be resolvable in all their essential aspects by brain analysis. Assuming that such limitations exist, objective analysis by the methods of natural science cannot, in principle, fully encompass subjective, mental experience.

An excerpt is below the fold:

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Okay, if English is not your first language, you can now read about the amazing proteins in Turkish or Portuguese.

Also, why is evolution so clever?

The biochemists studied yeast cells and found that mitochondria, which generates 90 percent of the cell's energy, can be the deciding factor "“ the "brain power" "“ behind how fast cells divide.

"The finding changes the traditional view of the mitochondrion from an "˜energy depot' at the service of its larger cellular host to a "˜command center' that directs cell division," Polymenis said.

Polymenis said the research showed that when a yeast cell's mitochondria decided to "turn on the switch," the cell's nucleus "“ which carries most of the genetic material "“ received the message and cell division began.

Here

Excerpts from:
Unrealistic fatalism in U.S. youth ages 14 to 22: prevalence and characteristics.
Jamieson PE, Romer D.
J Adolesc Health 2008 Feb;42(2):154-60.

Approximately 1 out of every 15 youth interviewed (6.7%, 95% confidence interval [CI] = 5.9%, 7.5%) responded that they agreed they would not live much past the age of 30.

Fatalistic youth engaged in greater suicidal planning, had more accepting attitudes toward suicide, were less attached to religion, and were more impulsive than other youth.

Youth who were more religious, both in identifying with a religion and attending services, were significantly less likely to be fatalistic, an effect that remained in the model despite controlling for suicide acceptance. In addition to not accepting suicide, religion may also act as a buffer against fatalism because it provides reasons for living that may help to counteract stressors that trigger feelings of hopelessness about the future [30"“32].

Let's consider more from the Hartwell et al. paper:

We argue here for the recognition of functional "˜modules' as a critical level of biological organization. Modules are composed of many types of molecule. They have discrete functions that arise from interactions among their components (proteins, DNA, RNA and small molecules), but these functions cannot easily be predicted by studying the properties of the isolated components.

Okay, a module is a) composed of many different parts such that b) the function stems from the interaction of those parts and c) a study of the isolated parts would not lead us to expect the function of the module. Would a module thus have an IC core?

These remind me of something.

Although living systems obey the laws of physics and chemistry, the notion of function or purpose differentiates biology from other natural sciences.

To describe biological functions, we need a vocabulary that contains concepts such as amplification, adaptation, robustness, insulation, error correction and coincidence detection.

A number of the design principles of biological systems are familiar to engineers. Positive feedback loops can drive rapid transitions between two different stable states of a system, and negative feedback loops can maintain an output parameter within a narrow range, despite widely fluctuating input. Coincidence detection systems require two or more events to occur simultaneously in order to activate an output. Amplifiers are built to minimize noise relative to signal, for instance by choosing appropriate time constants for the circuits. Parallel circuits (fail-safe systems) allow an electronic device to survive failures in one of the circuits.
Designs such as these are common in biology.

From molecular to modular cell biology
Leland H. Hartwell, John J. Hopfield, Stanislas Leibler and Andrew W. Murray

Here

HT:Rock

Richard Dawkins writes:

Arthur C. Clarke, who died last month, said, "Any sufficiently advanced technology is indistinguishable from magic." If we could land a jumbo jet beside a medieval village, would we not be worshiped as gods? The technology of interstellar travel, and the scientific knowledge on which it would be based, are as far beyond us as our present-day knowledge surpasses that of Dark Age peasants.

Indeed. This is why it is significant that looking at the cell is like looking into the future of our own designs. But it also undersores the limitations of Analogy, as we could be using a much more primitive technology (ours) to help us grasp a much more sophisticated technology (life).

Dawkins adds:

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I came across an old textbook entitled, The Principles of Heredity. It was written by geneticist Laurence H. Snyder and published in 1935 (Boston, New York [etc.] D.C. Heath and company). The book was intended as a text for "the beginning student of heredity." The textbook has a chapter on Eugenics that provides us a glimpse of one portion of our American and scientific history. Given that this material was being taught to students, I've transcribed this chapter and offer it merely as a service for those interested in the history of eugenics.

Here

Our semi-annoying, semi-enlightening commenter and sometimes contributor Thought Provoker has spent the better part of the past week valiantly attempting to defend Charles Darwin from Ben Stein's charge in the movie Expelled that Darwinism led to eugenics, and eugenics led to Adolph Hitler's eugenics laws, which led to… The Holocaust.

I admit to sensitivity on this issue, as both my Godparents were Jews, very recent immigrants from Europe. Both of them had tattoos and had lost their entire families in the Holocaust. They never had any children of their own. Can you guess why? So I got 'indoctrinated' very young in the importance of what Never Again! means.

My husband's Aunt Melba (still spry but blind at 96) was sterilized as an adolescent when she and her sister were dropped off at an orphanage back when being an orphan was considered a symptom of "undesirable genetic inheritance" in America. So both sides of this family have some eugenics horror stories in the family album and a serious commitment to making sure it never happens again.

These family stories are related. Such things were as common when I was growing up as unfortunate survivors of polio and thalidomide babies and radiation-induced cancer clusters from atmospheric bomb testing. What happened to my Godparents had its insidious roots in what happened to Aunt Melba years earlier in Oklahoma. Direct, irrefutable connections, as history amply documents in collections from Cold Spring Harbor to the Holocaust Museum.

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