Intelligent Design Theory: Science or Religion?

rosborne,

Farmerman mentioned recently that he may not be able to post until around Christmas time.

since Darwin had specific roots in the Indusrial Revolution that are no longer relevant.

December 10, 2006
Study Detects Recent Instance of Human Evolution
By NICHOLAS WADE

A surprisingly recent instance of human evolution has been detected among the peoples of East Africa. It is the ability to digest milk in adulthood, conferred by genetic changes that occurred as recently as 3,000 years ago, a team of geneticists has found.

The finding is a striking example of a cultural practice ?- the raising of dairy cattle ?- feeding back into the human genome. It also seems to be one of the first instances of convergent human evolution to be documented at the genetic level. Convergent evolution refers to two or more populations acquiring the same trait independently.

Throughout most of human history, the ability to digest lactose, the principal sugar of milk, has been switched off after weaning because there is no further need for the lactase enzyme that breaks the sugar apart. But when cattle were first domesticated 9,000 years ago and people later started to consume their milk as well as their meat, natural selection would have favored anyone with a mutation that kept the lactase gene switched on.

Such a mutation is known to have arisen among an early cattle-raising people, the Funnel Beaker culture, which flourished some 5,000 to 6,000 years ago in north-central Europe. People with a persistently active lactase gene have no problem digesting milk and are said to be lactose tolerant.

Almost all Dutch people and 99 percent of Swedes are lactose-tolerant, but the mutation becomes progressively less common in Europeans who live at increasing distance from the ancient Funnel Beaker region.

Geneticists wondered if the lactose tolerance mutation in Europeans, first identified in 2002, had arisen among pastoral peoples elsewhere. But it seemed to be largely absent from Africa, even though pastoral peoples there generally have some degree of tolerance.

A research team led by Sarah Tishkoff of the University of Maryland has now resolved much of the puzzle. After testing for lactose tolerance and genetic makeup among 43 ethnic groups of East Africa, she and her colleagues have found three new mutations, all independent of each other and of the European mutation, which keep the lactase gene permanently switched on.

The principal mutation, found among Nilo-Saharan-speaking ethnic groups of Kenya and Tanzania, arose 2,700 to 6,800 years ago, according to genetic estimates, Dr. Tishkoff's group is to report in the journal Nature Genetics on Monday. This fits well with archaeological evidence suggesting that pastoral peoples from the north reached northern Kenya about 4,500 years ago and southern Kenya and Tanzania 3,300 years ago.

Two other mutations were found, among the Beja people of northeastern Sudan and tribes of the same language family, Afro-Asiatic, in northern Kenya.

Genetic evidence shows that the mutations conferred an enormous selective advantage on their owners, enabling them to leave almost 10 times as many descendants as people without them. The mutations have created "one of the strongest genetic signatures of natural selection yet reported in humans," the researchers write.

The survival advantage was so powerful perhaps because those with the mutations not only gained extra energy from lactose but also, in drought conditions, would have benefited from the water in milk. People who were lactose-intolerant could have risked losing water from diarrhea, Dr. Tishkoff said.

Diane Gifford-Gonzalez, an archaeologist at the University of California, Santa Cruz, said the new findings were "very exciting" because they "showed the speed with which a genetic mutation can be favored under conditions of strong natural selection, demonstrating the possible rate of evolutionary change in humans."

The genetic data fitted in well, she said, with archaeological and linguistic evidence about the spread of pastoralism in Africa. The first clear evidence of cattle in Africa is from a site 8,000 years old in northwestern Sudan. Cattle there were domesticated independently from two other domestications, in the Near East and the Indus valley of India.

Both Nilo-Saharan speakers in Sudan and their Cushitic-speaking neighbors in the Red Sea hills probably domesticated cattle at the same time, since each has an independent vocabulary for cattle items, said Dr. Christopher Ehret, an expert on African languages and history at the University of California, Los Angeles. Descendants of each group moved southward and would have met again in Kenya, Dr. Ehret said.

Dr. Tishkoff detected lactose tolerance among both Cushitic speakers and Nilo-Saharan groups in Kenya. Cushitic is a branch of Afro-Asiatic, the language family that includes Arabic, Hebrew and ancient Egyptian.

Dr. Jonathan Pritchard, a statistical geneticist at the University of Chicago and the co-author of the new article, said that there were many signals of natural selection in the human genome, but that it was usually hard to know what was being selected for. In this case Dr. Tishkoff had clearly defined the driving force, he said.

The mutations Dr. Tishkoff detected are not in the lactase gene itself but a nearby region of the DNA that controls the activation of the gene. The finding that different ethnic groups in East Africa have different mutations is one instance of their varied evolutionary history and their exposure to many different selective pressures, Dr. Tishkoff said.

"There is a lot of genetic variation between groups in Africa, reflecting the different environments in which they live, from deserts to tropics, and their exposure to very different selective forces," she said.

People in different regions of the world have evolved independently since dispersing from the ancestral human population in northeast Africa 50,000 years ago, a process that has led to the emergence of different races. But much of this differentiation at the level of DNA may have led to the same physical result.

As Dr. Tishkoff has found in the case of lactose tolerance, evolution may use the different mutations available to it in each population to reach the same goal when each is subjected to the same selective pressure. "I think it's reasonable to assume this will be a more general paradigm," Dr. Pritchard said.

I came here looking for a discussion thread about science and religion, after listening to a radio show today, "Debating Darwin" on national public radio's "To the Best of Our Knowledge," part of a series "Electronics to Enlightenment" on science and religion. The show/s can be heard from the website http://wpr.org/book/

Teaching Biology Means Teaching Evolution
(University of Arkansas Press Release, December 11, 2006)

Evolution is a complex topic for any science teacher, given the misconceptions that some students bring to the classroom and the gaps that can occur in teacher preparation. In Investigating Evolutionary Biology in the Laboratory, William F. McComas writes that evolution is "the most important, most misunderstood, and most maligned concept in the syllabus - if it even appears in the syllabus."

McComas wrote the book's introductory sections, which engagingly explain the science of evolution and the challenges of teaching this core principle of biology.

These chapters are also a valuable resource for parents and others concerned about science education. In a succinct account of the development of understanding of evolution by Darwin and other scientists, McComas suggests that studying the actual history of the theory would teach students more about science in general and evolution in particular than the myths employed by most textbooks.

McComas, professor of science and technology education at the University of Arkansas, edited Investigating Evolutionary Biology and wrote several chapters. He assembled a host of scholars with rich research and classroom experience to write chapters that examine legal issues, review teaching strategies and present laboratory activities. He begins by establishing the centrality of evolution to modern biology.

"Without evolution, biology would simply be little more than a kind of ?'natural history stamp collecting' in which individual species are discarded, examined and identified as individual entities with no apparent link between them and anything else in the living world," he writes.

McComas makes an important distinction between the fact of evolution and the theory of natural selection - the theory that explains how evolution works. He discusses briefly the overwhelming scientific support for evolution as fact. The evidence for the natural principle of change through time, he writes, "is awesome and no one who has studied even a fraction of the data can seriously doubt that evolution has occurred."

While McComas calls the theory of natural selection "one of the most useful and encompassing in all of biology," he notes that scientists have continued to evaluate and enhance the theory. Any controversies among scientists about evolution, he emphasizes, "involve fine points of the explanation, not its ultimate validity or utility."

His chapter on "Cognitive Challenges of Evolution Education" discusses the deep-seated misconceptions that students bring to the classroom, including misunderstandings about the sources of variation, the mechanisms of inheritance of characteristics and adaptation.

"It is interesting to note that many misconceptions about evolution held by students mirror the views offered by 18th and 19th century naturalists who proposed explanations for the diversity of life on Earth," McComas writes.

Such misconceptions include the notions that organisms choose to change to meet a specific goal, that all organisms progress from less complex to more complex forms or that characteristics acquired by individuals can be inherited or passed down to their children. Even at the college level, student misunderstandings of evolution are not related to whether they believe the theory to be true or untrue.

Many high school science teachers "are not well prepared in either the theory or the evidence for evolution and therefore have difficulty conveying these complex ideas to students," McComas writes. When surveyed about their preparation for teaching science, "many teachers do not recall ever having taken college-level science coursework that incorporated evolution," and most "do not even recall hearing the word evolution in their college biology courses."

"Unfortunately, it is not enough to teach about evolution as if it were just another topic in biology," McComas writes. "The range of misconceptions is simply too great even if one discounts the complication of creationist and other non-scientific counterarguments."

McComas identifies instructional methods that engage students in testing both natural selection and competing models and that have been shown to produce a marked improvement in student understanding of fundamentals of science and evolution. Experience with these models shows that "when students' misconceptions are addressed proactively, students are likely to accept the scientific explanation."

"The recommendation is clear," McComas writes. "School laboratory practice should be directed away from confirmation and toward authentic investigations so that students have an opportunity to explore rather than just reiterate vital ideas in science. This approach will require that educators give evolution education the prominence it deserves both as a foundation principle in biology and because evolution and natural selection are pedagogically complex topics."

Biologist speaks for intelligent design
(By Dave Toplikar, Lawrence Journal-World, December 8, 2006)

Penguins, yes. Flagella, no.

One of the nation's leading proponents of intelligent design told a Kansas University audience Thursday that Darwinism or evolution can explain how, in the absence of predators, a bird might lose its ability to fly and begin to walk on the ground.

But it can't explain how complex living systems are built ?- the designs are too complex to have been randomly generated, said Michael Behe, author of "Darwin's Black Box: The Biochemical Challenge to Evolution."

Behe's lecture, titled "The Argument for Intelligent Design in Biology," was part of the "Difficult Dialogues" lecture series sponsored by KU's Hall Center for the Humanities and KU's Biodiversity Institute. About 100 people attended.

A professor of biology at Lehigh University, Behe's main argument was that evolution has become so ingrained and accepted that it becomes difficult to raise any questions about it in the scientific community.

"When I start to point out problems, often people don't have time to listen," he said.

He said intelligent design was not a philosophy, but a scientific conclusion that uses inductive reasoning.

"An inductive conclusion is a scientific conclusion," he said.

He listed several points, including:
• The intelligent design argument is "not a mystical conclusion." He said the design argument is a recognition there is a "purposeful arrangement" of the parts that make up an organism.
• He said "everyone agrees" that aspects of biology include the appearance of design. Cells appear to be arranged as a collection of complex molecular machines, he said.
• He said he recognizes evolution has occurred but it doesn't explain everything.

For example, random mutation and natural selection can't explain how complex mechanisms, such as the whiplike flagella "motors" that propel bacteria, developed, he said. So that leads to one controversial conclusion: They were designed that way, he said.

Behe also said some complex biological parts are irreducible ?- if you take them apart, they no longer have the same function.

During a question-and-answer session, Leonard Krishtalka, director of KU's Biodiversity Institute, asked Behe how he could know the mind of God well enough to determine how far an organism's parts could be reduced to nondesigned components.

Behe said he has been careful not to say "God did it" when speaking about the structure of the flagellum being irreducible.

"It just says that an intelligent designer was involved," Behe said. "We deduce design from the purposeful arrangement of parts."

Behe said he doesn't get into questions of who the designer is or how and when the design was done.

"I do not claim to know the mind of God," he said.

MICHAEL BEHE UPDATE

Quote:

Biologist speaks for intelligent design
(By Dave Toplikar, Lawrence Journal-World, December 8, 2006)

Behe also said some complex biological parts are irreducible ?- if you take them apart, they no longer have the same function.

wandeljw wrote:

MICHAEL BEHE UPDATE

Quote:

Biologist speaks for intelligent design
(By Dave Toplikar, Lawrence Journal-World, December 8, 2006)

Behe also said some complex biological parts are irreducible ?- if you take them apart, they no longer have the same function.

Behe doggedly adheres to this position even though the basic premis of his argument has been demonstrated to be incorrect.

Well, he's still sellin' books, right?

One of the nation's leading proponents of intelligent design told a Kansas University audience Thursday that Darwinism or evolution can explain how, in the absence of predators, a bird might lose its ability to fly and begin to walk on the ground.

But it can't explain how complex living systems are built ?- the designs are too complex to have been randomly generated, said Michael Behe, author of "Darwin's Black Box: The Biochemical Challenge to Evolution."

Quote:

One of the nation's leading proponents of intelligent design told a Kansas University audience Thursday that Darwinism or evolution can explain how, in the absence of predators, a bird might lose its ability to fly and begin to walk on the ground.

But it can't explain how complex living systems are built ?- the designs are too complex to have been randomly generated, said Michael Behe, author of "Darwin's Black Box: The Biochemical Challenge to Evolution."

Sounds like Behe is doing what primitive humans have been doing for eons; attributing what they don't understand to the supernatural. Behe seems to think we know all there is to know today so if we don't understand the creation of complex structures than we must attribute it to the supernatural world. In effect Behe is saying our knowledge will never allow us to understand it so God must be the answer.