Read Travelers in Endless Space on Exercise in Futility.
[Hat Tip: Primordial Blog]
Welcome to edition 34 of Gene Genie, the blog carnival of genes and genetic conditions.The beautiful logo was created by Ricardo at My Biotech Life.
It’s high summer, and the internet is a dead as a doornail, but a few diligent bloggers are still slogging away at the keyboard while everyone else is at the beach.
My newest project has taken me in exciting new directions. My latest book (Evolving God, Doubleday, January 2007) explores the deepest roots of the human religious imagination. Although I definitely do not think apes are religious, I do think that the empathy and compassion and meaning-making shown by apes in the wild and in captivity points us towards clues for understanding the precursors of religion in our earliest hominid ancestors. I trace the evidence for religious, symbolic ritual throughout human prehistory, culminating in the burial rites and art of Neandertals and Homo sapiens.I don't think it's an exaggeration to say that most people found her talk confusing. Her main point wasn't at all clear. Was she really arguing that non-human ape behavior might be a precursor of religion? Was she making a connection between religion and "empathy and compassion"? If so, what is the connection?
1. The theater class took a course on the play Inherit the Wind. Apparently, the staging of the original play is remarkable. That group also discussed the differences between the real trial and the one in the play and the influence of McCarthyism. I wish I could have taken that course last week, and many others.
These clarifications are important, because much of the criticism of EoE has been botched significantly. The book is bad, really bad, but it can't be honestly characterized as an anti-evolution argument.Many reviews of The Edge of Evolution are not as good as one might expect from scientists who have read the book.
I. Behe's assumption of a particular mutation rate is both absurdly oversimplified and inappropriately extrapolated into the entire tree of life.I don't think this is very important. Behe uses a mutation rate of 10-8 per generation and that's pretty accurate for mammals. A better mutation rate would be 10-10 nucleotides per DNA replication (cell generation) [Mutation Rates]. Yes, it's true that different species have different numbers of cell divisions per generation, so Behe should have mentioned this. Bacteria, for example, have a mutation rate of 10-10 per generation because there's only one cell division per generation. (In mammals there are about 100 cell divisions, hence the mutation rate per generation is 100 times greater.)
The basis of all of Behe's calculations is a mutation rate of 1 in 100 million. This is the estimated rate at which misspelling-type mutation occurs in each generation, averaged over the entire genome, in humans. (The number doesn't consider other types of mutation, now known to be more common than previously thought.) Behe uses this number in all of his (flawed) probability calculations. Even if we knew nothing about mutation rates, the notion of extrapolating from an human (or even mammalian) characteristic to the whole of the biosphere (past and present) is ludicrous enough that it would by itself cast doubt on the credibility of the author.
III. Behe claims that huge population sizes automatically generate more evolutionary opportunity than smaller ones do. This is incorrect.I thought Behe was right about this. There are more mutations, and more variation, in large populations than in small ones. I thought that one of the flaws in Behe's argument is that he doesn't take into account the existence of abundant neutral and nearly-neutral alleles in a large population. Many of these contribute to the double mutations that he requires.
It seems so obvious. More organisms means more mutations means more beneficial mutations means more and faster evolution. It's the kind of obvious, simplistic, intuitive claim that forms the bedrock of any folk science. But it's wrong.
On the contrary, very large population sizes lead to a so-called "speed limit" on adaptation that results from competition among beneficial mutations. The phenomenon is called clonal interference and it's particularly well understood in asexual organisms such as bacteria. The basic idea has been around for decades, but measurement and modeling of the phenomenon has been increasing in the last ten years. A very recent report, the subject of an upcoming post here, showed that the beneficial mutation rate in bacteria is 1000 times higher than previously thought – and the underestimation is due entirely to clonal interference.
The effect is not limited to asexual organisms; in fact, the problem of clonal interference is thought to constitute one of the major driving forces behind the evolutionary development and maintenance of sexual reproduction. The idea is that the genetic shuffling that accompanies sexual reproduction can bring beneficial mutations together and increase the effectiveness of selection.
According to Neil Tyson, Issac Newton was the greatest scientist who ever lived. Dr. Tyson, who is about the size of an NFL linebacker, is not a man I would care to have a disagreement with.I don't want to engage in a wrestling match with Neil DeGrasse Tyson. Surely we can settle this issue peacibly?
[Image Comment: The woman in the photograph is the only living descendant of Jesus. How appropriate that she's almost standing on the tomb of Charles Darwin!]
"for the development of radioimmunoassays of peptide hormones"
Your Majesties, Your Royal Highnesses, Ladies and Gentlemen,
The word "hormones" and associated terms have always stimulated our fantasy. The mystery in connection with hormones has been, from the beginning, equally overwhelming to the researcher and the layman. It is easy to understand why. These were chemical substances with often very powerful actions at concentrations which for a long time seemed so low that they were impossible to measure. However, mystery and belief lead nowhere, at least not in scientific research and medicine. Once one learned to identify the active chemical substances - in this case hormones - and to measure their rate of synthesis, only then did one establish a firm basis for turning fantasy and mystery into reality.
This year's three Nobel laureates in medicine have all made contributions which are outstanding examples of this kind of activity. Rosalyn Yalow's name is for ever associated with her methodology of measuring the presence of hormones in the blood at concentrations as low as one thousand billionths of a gram per milliliter of blood. This was a necessity, since a great many hormones, primarily the so-called protein hormones, are present in the blood in such small quantities. Before Yalow, these hormones could not be determined quantitatively in the blood, and therefore, active research in this field had stagnated.
Rosalyn Yalow and Solomon Berson, her late coworker, discovered by chance that one small protein hormone, insulin, following injection into man resulted in a production of antibodies against insulin. All diabetics who receive insulin develop similar antibodies against the administered insulin. The discovery by Yalow and Berson was unacceptable at first - their first scientific paper concerning this observation was even refused publication - since it was commonly believed that proteins as small as these protein hormones were unable to stimulate antibody formation. However, Yalow and Berson did not give up, and furthermore, after a couple of years of intensive work, they presented in 1960 a methodology for the determination of protein hormones in the blood, the fundamental principle of which utilized the ability of these hormones to stimulate antibody formation in man. This methodology, known as the Yalow-Berson method, is genial in all its simplicity, and can even be described in simple terms.
As a result of mixing in a test tube a known quantity of radioactive insulin with a known quantity of antibodies against insulin, a specific amount of the insulin becomes attached to these antibodies. Subsequently, if one adds to this mixture a small amount of blood which contains insulin, the insulin of the blood becomes similarly attached to the antibodies and a certain portion of the radioactive insulin is detached from the antibodies. The higher the concentration of insulin is in the blood sample, the larger is the amount of radioactive insulin that will be detached from the antibodies. The amount of radioactive insulin thus removed can easily be determined, providing an exact measure of the amount of insulin present in the blood sample.
The Yalow-Berson method which makes it possible to determine the exact amounts of all hormones present, represented a real revolution in the field of hormone research. A field where one refers to the time period before Yalow, and the new epoch which began with her achievement. Her methodology and the modifications thereof, subsequently made their triumphant journey far beyond her own field of research, reaching into vast territories of biology and medicine. It has been said that Yalow changed the life of a multitude of researchers within these fields. Rarely have so many had so few to thank for so much.
Roger Guillemin and Andrew Schally have also contributed greatly to this field of research, exploring protein hormones. It is justifiable to say that they have uncovered a substantial part of the link between body and soul.
For decades, one has talked about the indivisible homo sapiens, maintaining that our body and soul can not be separated since they form an entity. Emotional and psychic phenomena do influence our bodily functions. Let me give you an example. When American soldiers were sent to the European war scene, thousands of female companions who were left behind, stopped menstruation. They were completely healthy, but the emotional stress had an influence on certain body functions, causing these functions to cease. Through which mechanisms did the psyche thus influence the body?
Psychic phenomena as well as input from the entire body bring about electrical impulses in the brain. This is the language of the nervous system, the brain speaks "electrically". The brain informs some of its centers of what is going on, and these centers relay the message further. Those centers which pass on the information to the hormone producing organs of the body are situated in the midbrain, an area on the base of the brain. Delicate blood vessels in turn connect the midbrain with the pituitary, an important hormone producing gland, often referred to as the hypophysis. This sequence provides the pathway for transmission of information from the surroundings to the brain, to the midbrain, to the pituitary, and thus to all those bodily functions which are influenced and controlled by hormones.
By the mid 1950's it was evident - also here through the contributions of Guillemin and Schally - that the midbrain produces chemical substances which are transported to the pituitary via the delicate blood vessels just mentioned. Once in the pituitary, they determine the exact quantities of the various hypophyseal hormones which must be produced at a given point in time. But which were these substances in the midbrain, evidently passing the information from soul to body?
Guillemin and Schally worked independently in different parts of the U.S.A. together with their large staff of coworkers, trying to isolate one of these chemical substances, and both researchers concentrated on the same substance. Each started with five million pieces taken from the midbrain of sheeps and pigs - half a ton - and in 1969, after years of arduous labor, they each came up with 1 milligram of the purified hormonal substance. Rarely have so many gained so little from so much.
Guillemin and Schally were the first to isolate several of the communicating chemical links between the brain and the pituitary, and they also determined their structure and succeeded in synthesizing them.
The discoveries by Guillemin and Schally brought on a revolution in their own field of research. Still other protein hormones have subsequently been isolated from the midbrain, this wondrous organ of control and guidance which today - more than ever - emerges as part of the link between the body (soma) and the soul (brain).
Rosalyn Yalow, Roger Guillemin, Andrew Schally: the road of every scientist is paved by frustration. But some reach the goal they have set up and enjoy the pleasure and excitement of having learned something that no one knew before, and for that enjoy imperishable honor in the learned world.
Few ever reach the point at which you have arrived: to undertake a formidable task and to come to a solution, which not only attracts the admiration of your scientific colleagues, but which - in the best spirit of Alfred Nobel - also contains a possibility to understand the structure of human life and human behaviour.
The Karolinska Institute is happy to be able to award you this year's Nobel Prize in Physiology or Medicine for your contributions and congratulates you. May I now ask you to receive the insignia of the Nobel Prize from His Majesty, the King.
We are now descending into a frenzy of Darwin celebrations, and you’re not going to escape it until the end of 2009. We’ve got his 200th birthday in February, and the 150th anniversary of the publication of the Origin of Species in November. The spotlight is going to be on Darwin, and Darwin alone.This reflects one of the main themes in the two courses that I taught at Chautauqua; namely, that Darwin was the greatest scientist who ever lived but we have moved far beyond what Darwin knew in 1859.
I think this is a mistake. Darwin deserves celebrating, but that doesn’t mean we should fall prey to a cult of personality. Darwin did not invent biology. Darwin did not even find most of the evidence that he used to back up his theory of evolution. And he certainly did not discover all there was to know about evolution. Biologists have discovered many new things about evolution since his time. In some cases, they’ve challenged some of his most important arguments. And that’s fine. That’s the great strength of science.
1. The other one was Genie Scott.
2. The original Modern Synthesis of the 1940's was pluralistic.
3. Financially.