NCSE has now signed up more than 1,000 Scientists named Steve.

The National Center for Science Education has now signed up more than 1,000 scientists named "Steve." Here's the petition that all 1082 Scientist Steves have signed:

Evolution is a vital, well-supported, unifying principle of the biological sciences, and the scientific evidence is overwhelmingly in favor of the idea that all living things share a common ancestry. Although there are legitimate debates about the patterns and processes of evolution, there is no serious scientific doubt that evolution occurred or that natural selection is a major mechanism in its occurrence. It is scientifically inappropriate and pedagogically irresponsible for creationist pseudoscience, including but not limited to "intelligent design," to be introduced into the science curricula of our nation's public schools.

Continue ReadingNCSE has now signed up more than 1,000 Scientists named Steve.

Kenneth Miller’s unrelenting attack on creationism

Kenneth Miller is a professor of biology at Brown University. He is also a widely published author (co-author of high school and college biology textbooks used by millions of students). He is also a practicing Roman Catholic who has served as an expert in several court cases concerning creationist school boards that have tried to muzzle classroom science. In his most recent book, Only a Theory: Evolution and the Battle for America's Soul, Miller makes an unrelentingly strong case against creationists of all stripes, including those who advocate "intelligent design." I did not realize the strength of the scientific case based upon the analysis of the genomes of human beings and other animals. How strong is it? It is at least as strong as the fossil record, arguably much stronger. I already knew a few things about the arguments based on genome analyses. For instance, I had often read that the genomes of chimpanzees and humans were 99% the same (or, at least, 96% the same). I also knew that all animals possessed Hox genes, essentially "toolkits for generating body form." Miller reminds us that "it is the same kit whether that animal is a honey bee, a fish or an elephant." The Hox genes prove "deep connections between animal groups." Miller points out that these similarities are even much more striking than Haeckel's (admittedly exaggerated) embryonic drawings. In fact, Haeckel "actually understated the evolutionary case each of these embryos possesses the same developmental toolkit, revealing both are common ancestry and the similarity of form and function produced by the workings of the evolutionary process." These profound Evo-Devo findings (the combination of development and the study of evolution) show that we "no longer need to make a distinction between the two types of change known as macro evolution and micro evolution. We don't need to attribute special mechanisms for large-scale changes. Evo-devo "reveals that macro evolution is the product of microevolution writ large." According to Miller, these should be "chilling words" to the ID crowd.

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Bacteria that talk to each other

Bonnie Bassler, who teaches molecular biology at Princeton, explains that bacteria don't just grow and divide, grow and divide. They speak to each other and with other species of bacteria through their chemicals. Bassler studies how bacteria use chemical signals to act as coordinated social units. In this delightful TED talk, Bassler discusses how her research group has studied the manner in which bacteria talk to each other. They make chemical "words" to enable group activities (such as triggering the timing for effective virulence attacks), sensing each other through their "quorum-sensing molecules." They can also sense the difference between themselves and other bacteria. Note that each of us is 99% bacterial. Our human body consists of about one trillion of "our own" cells, but ten trillion bacteria. We have about 30,000 of "our own" genes, but we carry about 100 times more bacterial DNA than human DNA. Bacteria live as "mutualists" with us. They help us digest our food, make our vitamins, protects us from other pathogens and help us survive in numerous other ways. Rather than using antibiotics to kill bacteria (which inevitably selects for more virulent strains), Bassler suggests that a better understanding of the communications schemes used by bacteria is allowing scientists to develop potent new medicines. This is an upbeat and informative talk regarding a most ancient form of life.

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The not-simple question of defining “species”?

There are a lot of simple things out there that aren't really simple once you start trying to understand and explain them. The concept of "species" is one of those non-simple concepts. I had assumed that I had a good gut understanding of "species" until I read an article called "Speciation," by Andrew P. Hendry, published in the March 12, 2009 edition of Nature (available online only to subscribers). Hendry suggests that the term "species" as a technical classification in the field of biology is "ambiguous and amorphous." He starts by quoting Darwin, from on the origin of species: In short, we shall have to treat species in the same manner as those naturalists treat genera, who admit that genera are merrily artificial combinations made for convenience. This may not be a cheering prospect; but we shall at least be free from the vain search for the undiscovered and undiscoverable essence of the term species. Hendry suggests that modern biological research has proved Darwin. No universal easily applicable concept of "species" exists; instead, more than two dozen approaches exist with regard to "species." The most common version is the "biological species concept" (BSC). This definition holds that species are "groups of actually or potentially interbreeding individuals that are reproductively isolated from other such groups (that is, they exchange few genes). Hendry elaborates: The BSC is sometimes interpreted to imply the extreme situation where two groups are separate species only when successful hybrids cannot ever be produced-and any two such groups certainly are separate species. But many other groups that are widely accepted to represent separate species frequently violate the strict criteria; for example, some estimates hold that 25% of all plant species and 10% of all animal species hybridize successfully with at least one other species. Probably for this reason, the BSC is often relaxed to the point that different groups are considered separate species if they can maintain their genetic integrity and nature. This more useful, albeit more ambiguous, criterion allows for some genetic exchange (gene flow) between species as long as they do not become homogenized. Hendry then goes on to discuss various challenges to BSC.

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Charles Darwin’s exceedingly dangerous idea

In Darwin's dangerous Idea: Evolution and the Meanings of Life, Daniel Dennett describes Darwin's idea as the "best idea anyone has ever had."

In a single stroke, the idea of evolution by natural selection unifies the realm of life, meaning, and purpose with the realm of space and time, cause and effect, mechanism and a physical law. But it is not just a wonderful scientific idea. It is a dangerous idea.

What exactly was Darwin's dangerous idea? According to Dennett, it was "not the idea of evolution, but the idea of evolution by natural selection, an idea he himself could never formulate with sufficient rigor and detail to prove, though he presented a brilliant case for it." (42) Dennett considers Darwin's idea to be "dangerous" because it has so many fruitful applications in so many fields above and beyond biology. When Dennett was a schoolboy, he and some of his friends imagined that there was such a thing as "universal acid,"

a liquid "so corrosive that it will eat through anything! The problem is: what do you keep it in? It dissolves glass bottles and stainless steel canisters as readily as paper bags. What would happen if you somehow came upon or created a dollop of universal acid? With the whole planet eventually be destroyed? What would it leave in its wake? After everything had been transformed by its encounter with universal acid, what would the world look like? Little did I realize that in a few years I would encounter an idea-Darwin's idea-bearing an unmistakable likeness to universal acid: eats through just about every traditional concept, and leaves in its wake a revolutionized world-view, with most of the old landmarks are still recognizable, but transformed in fundamental ways.

(63) Darwin's idea is powerful, indeed. Many people see it as having the power to ruin the meaning of life.

People fear that once this universal acid has passed through the monuments we cherish, they will cease to exist, dissolved in an unrecognizable and unlovable puddle of scientific destruction.

Dennett characterizes this fear is unwarranted:

We might learn some surprising or even shocking things about these treasures, but unless our valuing these things was based all long on confusion or mistaken identity, how could increase understanding of them diminish their value in our eyes? (82)

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