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Fodor, Nagel, and Plantinga don’t need to turn themselves into biochemists, but some awareness of the issues and advances would not be entirely misplaced.
By Michael Ruse, Chronicle Review, March 7, 2010
Last year was the 200th anniversary of the birth of Charles Darwin and the 150th anniversary of the publication of his book, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. The anniversary was marked by conferences the world over. I will not tell you how many I attended; ecologically sensitive readers of The Chronicle might start whining about carbon footprints and that sort of thing. Let me just say that I found myself going no fewer than three times through the Quad City International Airport, in Moline, Ill. Moline!
I mention this as background to the publication of a new book by Jerry A. Fodor, a professor of philosophy at Rutgers University, and Massimo Piattelli-Palmarini, a professor of cognitive science at the University of Arizona. The title of the book, What Darwin Got Wrong (Farrar, Straus and Giroux), tells you their opinion of the old English naturalist and of his theory of evolution through natural selection. If Fodor and Piattelli-Palmarini were an isolated case, one could dismiss their book with a grimace (if you were a biologist), or welcome them with a cheer (if you were a creationist). But in the philosophical community, there is an increasingly vocal cadre of eminent philosophers harboring doubts about Darwin. To understand their critique, we must first put the clock back a year, to the beginning of the celebrations.
The anniversary conferences usually had a smattering of professional Darwin types like me—I am a historian and philosopher of science specializing in evolutionary theory—but the bulk of the presenters and attendees were evolutionary biologists. For two reasons, the atmosphere was universally positive. First, scientists deeply respect Darwin and his achievements. These people are evolutionists—they take the past seriously. Second, there was not a person at these conferences who was not excited about the science today. Evolutionary biology is on a roll, and that was a cause for celebration—and frenetic presentations that jammed in as much new science as possible. Moreover, to a person, the scientists saw that the first point led smoothly into the second. Everyone appreciates the tools of Darwinism, above all the mechanism of natural selection. But great science doesn’t stand still. It picks up and carries ideas and findings way beyond the wildest hopes of its founders. Evolutionary biology today is deeply Darwinian, but it has outpaced the Origin in ways that its author could never have imagined. To use a hackneyed phrase, Darwin gave biology a paradigm, and biologists have been expanding it ever since.
Posted by CNP Webmaster as Evolutionary Biology, Opinion, Recent Posts, Science on March 8, 2010 - כ"ב אדר תש"ע at 3:15 pm
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What Darwin Got Wrong
Jerry Fodor and Massimo Piatelli-Palmarini
Farrar, Straus and Giroux, $26 (cloth)
Ned Block and Philip Kitcher
Boston Review, March/April 2010
In On the Origin of Species, published in 1859, Charles Darwin made two remarkable scientific contributions. First, he presented an overwhelming case for the relatedness of all living things. Biological diversity, he argued, results from a process of “transmutation” of species—via “descent with modification.” Second, he recognized that the basic mechanism of such change is natural selection: a combination of variations in traits and a selective retention of the variations that contribute to reproductive success.
Descent with modification was accepted quickly. As early as 1872, Thomas Henry Huxley described Darwin as having achieved a revolution comparable to that brought about by Newton’s Principia. Natural selection, by contrast, remained controversial until the 1930s, when Darwin’s ideas were integrated with the genetics of Gregor Mendel and Thomas Hunt Morgan, creating the “Modern Synthesis.” More than 70 years later, thanks to a proliferation of evolutionary explanations and significant new theoretical contributions, the fundamentals of evolutionary biology are reasonably well settled.
To be sure, religiously inspired opposition to evolution persists. Although religious opponents seem to have accepted—at least officially—the relatedness of organisms, proponents of “intelligent design” continue to insist that natural selection is unable to explain some prominent instances of evolutionary change. Their skepticism is based on alleged examples of “irreducible complexity”—an intricate interdependence in the features of organisms that supposedly cannot be explained by Darwinian mechanisms of step-by-step improvement.
Other critics—more sophisticated and scientifically informed—wonder whether natural selection explains as much about evolution as biologists commonly assert. They urge, for example, that causes other than natural selection (such as genetic drift) are important in explaining evolution. Or they argue—overemphasizing something all evolutionary biologists agree with—that natural selection operates against a background of constraints, perhaps stemming from features of genomes. Darwin himself was aware of these complexities about the role of natural selection, and throughout the Origin laments his own ignorance about the extent of that role and what alternative causes of evolutionary change there are. His awareness of how much he did not know led him to cautious formulations: for example, he writes, “Natural Selection has been the main but not exclusive means of modification.”
As in other areas of science, then, lively debate continues, and an interest in deeper and more comprehensive understanding moves the field forward. But even as some scientists suggest that natural selection may be limited in ways Darwin could not envisage, they accept his basic insights and work to improve our biological understanding within the framework he set forth.
Posted by CNP Webmaster as Evolutionary Biology, Recent Posts, Science on March 3, 2010 - י"ז אדר תש"ע at 8:27 am
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Mind Matters - March 2, 2010
By John Kelley, Scientific American
Answer: Yes!
In my view, both these statements are true: Antidepressants do work. And antidepressants don’t work. Not to put too fine a Clintonian point on it, but determining whether antidepressants work depends on the definition of the word “work.”
A controversial article just published in the prestigious Journal of the American Medical Association concluded that antidepressants are no more effective than placebos for most depressed patients. Jay Fournier and his colleagues at the University of Pennsylvania aggregated individual patient data from six high-quality clinical trials and found that the superiority of antidepressants over placebo is clinically significant only for patients who are very severely depressed. For patients with mild, moderate, and even severe depression, placebos work nearly as well as antidepressants.
There have been at least four other review articles published in the last eight years that have come to similar conclusions about the limited clinical efficacy of antidepressants, and one of the study authors, psychologist Irving Kirsch, has recently published a book on the topic, provocatively entitled The Emperor’s New Drugs: Exploding the Antidepressant Myth.
The recent review articles questioning the clinical efficacy of antidepressants run counter to the received wisdom in the psychiatric community that antidepressants are highly effective. Indeed, it wasn’t so long ago that psychiatrist Peter Kramer wrote in his best-selling book Listening to Prozac that this miracle drug made patients “better than well.” Prozac was a Rock Star. Its extraordinary success even led to a photograph of the green and white capsule on the cover of Newsweek Magazine in 1990.
The essential facts about antidepressant efficacy are not in dispute. In double-blind, randomized controlled trials – meaning that patients are randomly assigned to receive either drug or placebo, and neither patient nor clinician knows who gets what – antidepressants show a small but statistically significant advantage over placebos. The debate is over the interpretation of these findings, and it revolves around the distinction between clinical significance and statistical significance. Read the rest of this entry »
Posted by CNP Webmaster as Health Sciences, Mental Health, News Articles, Recent Posts, Science on March 3, 2010 - י"ז אדר תש"ע at 7:29 am
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By Thomas Rogers
Salon.com, Feb. 23, 2010 |
At this point, the idea of somebody publishing an attack on Charles Darwin isn’t exactly surprising. The 19th-century naturalist, and the man behind the theory of evolution, has never been a particularly popular figure among conservative Christians, and, these days, the anti-Darwin movement is a cottage industry. In the last year, which marked the bicentennial of Darwin’s birth and 150 years since the publication of “The Origin of the Species,” the man was even subjected to the peculiar indignity of an assault by former “Growing Pains” star Kirk Cameron.
But unlike most of these attacks, “What Darwin Got Wrong,” a new book by Jerry Fodor, a professor of philosophy and cognitive sciences at Rutgers University, and Massimo Piattelli-Palmarini, a professor of cognitive science at the University of Arizona, comes not from the religious right, but from two atheist academics with — surprise — a nuanced argument about the shortcomings of Darwin’s theories. Their book details (in very technical language) how recent discoveries in genetics have thrown into question many of our perceived truths about natural selection, and why these have the potential to undermine much of what we know about evolution and biology.
Salon spoke to Fodor over the phone from his home, about the problems with Darwin’s ideas, bloggers’ “obscene” comments on his work, and why Darwinism might be as unreliable as creationism. Read the rest of this entry »
Posted by CNP Webmaster as Education, Evolutionary Biology, Recent Posts, Science on February 24, 2010 - י' אדר תש"ע at 3:11 pm
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ScienceDaily (Feb. 22, 2010) — A section of an ancient city wall of Jerusalem from the tenth century B.C.E. — possibly built by King Solomon — has been revealed in archaeological excavations directed by Dr. Eilat Mazar and conducted under the auspices of the Hebrew University of Jerusalem.
The section of the city wall revealed, 70 meters long and six meters high, is located in the area known as the Ophel, between the City of David and the southern wall of the Temple Mount.
Uncovered in the city wall complex are: an inner gatehouse for access into the royal quarter of the city, a royal structure adjacent to the gatehouse, and a corner tower that overlooks a substantial section of the adjacent Kidron valley.
The excavations in the Ophel area were carried out over a three-month period with funding provided by Daniel Mintz and Meredith Berkman, a New York couple interested in Biblical Archeology. The funding supports both completion of the archaeological excavations and processing and analysis of the finds as well as conservation work and preparation of the site for viewing by the public within the Ophel Archaeological Park and the national park around the walls of Jerusalem.
Posted by CNP Webmaster as Education, Judaism, Middle East, Monotheistic Religions, News Articles, Science on February 22, 2010 - ח' אדר תש"ע at 8:09 pm
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ScienceDaily (Feb. 17, 2010) — Using arrays of long, thin silicon wires embedded in a polymer substrate, a team of scientists from the California Institute of Technology (Caltech) has created a new type of flexible solar cell that enhances the absorption of sunlight and efficiently converts its photons into electrons. The solar cell does all this using only a fraction of the expensive semiconductor materials required by conventional solar cells.
“These solar cells have, for the first time, surpassed the conventional light-trapping limit for absorbing materials,” says Harry Atwater, Howard Hughes Professor, professor of applied physics and materials science, and director of Caltech’s Resnick Institute, which focuses on sustainability research.
The light-trapping limit of a material refers to how much sunlight it is able to absorb. The silicon-wire arrays absorb up to 96 percent of incident sunlight at a single wavelength and 85 percent of total collectible sunlight. “We’ve surpassed previous optical microstructures developed to trap light,” he says.
Atwater and his colleagues — including Nathan Lewis, the George L. Argyros Professor and professor of chemistry at Caltech, and graduate student Michael Kelzenberg — assessed the performance of these arrays in a paper appearing in the February 14 advance online edition of the journal Nature Materials.
Atwater notes that the solar cells’ enhanced absorption is “useful absorption.”
“Many materials can absorb light quite well but not generate electricity — like, for instance, black paint,” he explains. “What’s most important in a solar cell is whether that absorption leads to the creation of charge carriers.”
The silicon wire arrays created by Atwater and his colleagues are able to convert between 90 and 100 percent of the photons they absorb into electrons — in technical terms, the wires have a near-perfect internal quantum efficiency. “High absorption plus good conversion makes for a high-quality solar cell,” says Atwater. “It’s an important advance.” Read the rest of this entry »
Posted by CNP Webmaster as Alternative Energy, Climate Change, Recent Posts, Science, Solar Energy on February 17, 2010 - ג' אדר תש"ע at 7:33 am
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ScienceDaily (Feb. 1, 2010) — A new study weighs in on the controversy over sex education, finding that an abstinence-only intervention for pre-teens was more successful in delaying the onset of sexual activity than a health-promotion control intervention. After two years, one-third of the abstinence-only group reported having sex, compared to one-half of the control group. The study by researchers at the University of Pennsylvania appears in the February 1 edition of the Archives of Pediatrics & Adolescent Medicine.
While abstinence-only intervention did not eliminate sexual activity all together, this is the first randomized controlled study to demonstrate that an abstinence-only intervention reduced the percentage of adolescents who reported any sexual intercourse for a long period, in this case two years, following the intervention.
"It is extremely important to find an effective intervention that delays sexual activity; the younger someone is when they have sex for the first time, the less likely they are to use condoms," said lead author John B. Jemmott III, PhD, professor of Communication in Psychiatry and of Communication at the University of Pennsylvania’s School of Medicine and Annenberg School for Communication. "Abstinence-only interventions may have an important role in delaying sexual activity until a time later in life when the adolescent is more prepared to handle to consequences of sex. This can reduce undesirable consequences of sex, including pregnancy and sexually transmitted infections like HIV/AIDS."
There was a 33 percent reduction in self-reported sexual intercourse from the abstinence-only group, compared to the control group, by the end of the study. Of the students who reported that they were sexually active during the study, there were fewer reports of recent sexual activity from the abstinence-only intervention participants (20.6 percent) compared to the control participants (29.0 percent).
Posted by CNP Webmaster as Education, Health Sciences, Recent Posts, Science on February 2, 2010 - י"ח שבט תש"ע at 5:10 am
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This is a single stem cell-derived neuron that has migrated away from the transplantation site in the cortex and grown into a mature neuron. The blue stain shows the nuclei of the endogenous neural cells in this part of the brain. (Credit: Courtesy, with permission: Weimann et al. The Journal of Neuroscience 2010.)
ScienceDaily (Jan. 24, 2010) — Transplanted neurons grown from embryonic stem cells can fully integrate into the brains of young animals, according to new research in the Jan. 20 issue of The Journal of Neuroscience.
Healthy brains have stable and precise connections between cells that are necessary for normal behavior. This new finding is the first to show that stem cells can be directed not only to become specific brain cells, but to link correctly.
In this study, a team of neuroscientists led by James Weimann, PhD, of Stanford Medical School focused on cells that transmit information from the brain’s cortex, some of which are responsible for muscle control. It is these neurons that are lost or damaged in spinal cord injuries and amyotrophic lateral sclerosis (ALS). "These stem cell-derived neurons can grow nerve fibers between the brain’s cerebral cortex and the spinal cord, so this study confirms the use of stem cells for therapeutic goals," Weimann said.
Posted by CNP Webmaster as Health Sciences, Mental Health, Recent Posts, Science on January 24, 2010 - ט' שבט תש"ע at 3:16 pm
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By Jo-Ann Heslin, MA, RD, CDN, Food & Nutrition Columnist ,Jan 17, 2010
HealthNewsDigest.com) – Carbohydrates, carbs, complex carbs, simple carbs, good carbs, bad carbs – help! In the last decade carbs have become a misunderstood nutrient. We went from high carb to low carb to being told to choose specific carbs. Before you can shop and eat wisely, you need to understand carbs.
Carbohydrates are the sugars, starches, and fibers found in food. All plant foods — fruits, vegetables, beans and grains — are rich in carbohydrates. Fruits have more sugar. Vegetables, beans and grains have more starch. Both have fiber. Sugars and starches are your body’s main sources of fuel (calories).
Sugar is a very important source of fuel. During digestion sugar molecules enter the bloodstream and travel to your body’s cells and to your brain where they are burned for energy. There are different types of sugar – simple sugars and others that are more complex.
Glucose is a simple sugar found in plants, animals, and in your blood as blood sugar. It is the only source of energy used by your brain. Fructose (fruit sugar) is also a simple sugar. Other sugars, sucrose (table sugar), lactose (milk sugar) and maltose (cereal sugar) are made up of two simple sugars that are broken apart in digestion before they can be burned for energy.
Posted by CNP Webmaster as Health Sciences, Nutrition & Fitness, Recent Posts, Science on January 18, 2010 - ג' שבט תש"ע at 4:50 am
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ScienceDaily (Jan. 7, 2010) — A breakthrough in the research of the Hebrew scriptures has shed new light on the period in which the Bible was written. Professor Gershon Galil of the Department of Biblical Studies at the University of Haifa has deciphered an inscription on a pottery shard discovered in the Elah valley dating from the 10th century BCE (the period of King David’s reign), and has shown that this is a Hebrew inscription. The discovery makes this the earliest known Hebrew writing.
The significance of this breakthrough relates to the fact that at least some of the biblical scriptures were composed hundreds of years before the dates presented today in research and that the Kingdom of Israel already existed at that time.
Prof. Gershon Galil of the University of Haifa who deciphered the inscription: “It indicates that the Kingdom of Israel already existed in the 10th century BCE and that at least some of the biblical texts were written hundreds of years before the dates presented in current research.”
A breakthrough in the research of the Hebrew scriptures has shed new light on the period in which the Bible was written. Prof. Gershon Galil of the Department of Biblical Studies at the University of Haifa has deciphered an inscription dating from the 10th century BCE (the period of King David’s reign), and has shown that this is a Hebrew inscription. The discovery makes this the earliest known Hebrew writing. The significance of this breakthrough relates to the fact that at least some of the biblical scriptures were composed hundreds of years before the dates presented today in research and that the Kingdom of Israel already existed at that time. Read the rest of this entry »
Posted by CNP Webmaster as Judaism, Middle East, Monotheistic Religions, News Articles, Recent Posts, Science on January 7, 2010 - כ"א טבת תש"ע at 11:32 pm
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