Teaching Evolution

A blog devoted to teaching evolution, both in our schools and in our communities.

Friday, April 29, 2005

Evolution Hall of Shame

A state legislator in Georgia has an interesting view:
A theory can be wrong. If it's wrong, or possibly could be wrong, don't teach it. Teach it with facts. If you've got facts to back it up, that's great,

That's Ben Bridges, a Republican from the Northern Georgia town of Cleveland. Dr. Sarah Pallas, a biology professor from Georgia State University has an intelligent and clear response:
The idea that matter is made of atoms is a theory. The idea that there is some kind of force that brings us back to earth if we jump up is a theory, it's called gravitational theory. If we're not allowed to talk about one theory, then we shouldn't be allowed to talk about all other theories.

Wednesday, April 27, 2005

How Did Great White Sharks Evolve?

Humans have a fascination with sharks, and they're one of the best animals to study from an evolutionary perspective because they lose their teeth so often that fossils abound everywhere sharks have lived. An interesting debate is shaping up about how the Great White evolved: Is it a descendent of the megladon or the mako? Chuck Ciampaglio an assistant professor of geology at Wright State University, has some answers.

Most scientists would probably say the Great Whites evolved from the megladon line, which existed from two million to twenty million years ago. They were huge sharks, approximately the length of a Greyhound bus and possessing teeth that were up to six inches long. However, our research, which is based on analyzing fossils of several hundred shark teeth, shows that the Great White shares more similarities with the mako shark.

Researchers use uses electron microscopes to examine different designs of digital images of shark teeth. This is the kind of great research that's currently going on in the field of evolution. It's a shame that all the general public knows about evolution is that a lot of people think it's incompatible with their religious faith.

Monday, April 25, 2005

Freedom to Teach a Different Pledge

I'd be curious to know where we're going to draw the line on these things. Now comes a guidance counselor who changed the Pledge of Allegiance from "one nation under God" to "one nation under your belief system" when she led her school's recitation.
Principal Kathleen Norton was out of the building during the incident, but apologized Thursday to the student body and today will be sending letters of apology to parents.

"It was completely inappropriate," Jefferson County School District Superintendent Cindy Stevenson said. "We completely believe any teacher or student has the right to follow their individual conscience, however, when leading children, you adhere to the Pledge of Allegiance."

How many of this guidance counselor's critics believe that a biology teacher, when leading children, should adhere to actual science and not creationism?

Hat tip: Washington Monthly

Friday, April 22, 2005

The Freedom to Teach Intelligent Design

Ugh. A lawyer for the Ann Arbor-based Thomas More Law Center says he's going to sue the Gull Lake Community Schools unless two middle school science teachers are allowed to include "intelligent design" in their science classes. What infuriates me is the news that these two teachers have been teaching this crap for two years, and they were only recently told to stop. This is a serious problem. Science teachers should be told in no uncertain terms that their job is to teach science, not to preach their religions.
But early this school year, the center says, the district superintendent ordered the teachers to stop teaching intelligent design and ordered related textbooks to be boxed up.

Thomas More president and chief counsel Richard Thompson said Thursday that violates academic freedom to teach and students' right to learn about controversy over evolution theory. He wrote a letter to the district's school board last week, and said he'll take the case to federal court if the district does not respond or take action by April 28.

So it's all about academic freedom. How do you suppose these folks feel about teachers' freedom to teach sex education?

Thursday, April 21, 2005

Odd Fly Uncovers Evolution Secret

Interesting news about the robber fly of the Canary Islands. Species like the robber fly, which tend to be confined to one area, are more common in places that have a wide variety of different species. Scientists think new species are more likely to evolve if they are surrounded by an already rich biodiversity. The article has a good overview of speciation:
It is thought "speciation" - the evolution of a new species - can occur when two populations of the same species become isolated, allowing them to "grow apart" genetically over the course of many generations.

Eventually, the two populations become so different that if they were to meet again they would no longer be able to breed, meaning they had become separate species.

One species can also evolve into another if strong selective forces are placed upon it (where certain genes or genetic traits are favoured by natural selection), or if its population is small enough to allow for "genetic drift", which happens when certain traits are lost - or become proportionately more common - simply because the gene pool has shrunk.

But exactly what drives speciation is still not fully understood by scientists, and it is an area of intense research.

Finally, take a look at the last four paragraphs:
Professor Axel Meyer, of Konstanz University in Germany, who is eminent in the field of speciation, says the research is very interesting - if it stands further scrutiny.

"It is very thought provoking," he told the BBC News website. "I'm sure it will have people rushing to their computers to see whether this pattern holds up and it will be interesting to see if it does hold up in other systems."

He also stressed that a rich biodiversity could not entirely explain a rich biodiversity because, of course, you had to start somewhere.

"They are saying that if you have biodiversity it will create more biodiversity - I can buy that. But it still doesn't explain the initial step: how do you get more biodiversity in the first place?"

Here is a fundamental difference between the scientists who study evolution and the proponents of creationism or intelligent design or whatever they want to call it. When scientists discuss evolution, they welcome questions. They don't just accept what they're told; they point to the next question that the new findings raise. Intelligent designers avoid questions; scientists seek them.

Wednesday, April 20, 2005

Book Recommendations

I have two books to recommend today, both of which look at evolution in interesting ways that textbook studying would miss.

The first is The Botany of Desire by Michael Pollan. The book explores four plants: apples, tulips, marijuana, and potatoes. With each plant, it discusses how human beings have played an important role in the plant's evolution, but also how the plants have affected human beings and in some ways forced humans to help them thrive. Among the many fascinating things I learned in this book is that John Chapman, the man better known as Johnny Appleseed, was actually interested in apples not because he wanted to spread a healthy fruit but because they could be turned into hard cider. For more on the subject, check out an interesting entry in the Straight Dope.

My second recommendation is Evolution's Workshop: God and Science on the Galapagos Islands by Edward J. Larson. The best chapter tells us about what Darwin saw in his trip to the Galapagos, but the whole thing is worth reading for its examination of the island chain at the center of evolutionary thought. I previously discussed another of Larson's books here.

Monday, April 18, 2005

Can Evolution Be Taught in Kansas?

This article disturbs me because it's starting to make me think that no matter how dedicated a science teacher might be in Kansas, it would be impossible for him or her to teach evolution effectively. So many parents have convinced their children not to let teachers teach them that man descended from monkeys that nothing a good teacher can say will get through.
But James Calvert, of Lake Quivira, a national proponent of intelligent design, says it is the pro-evolution forces that are intolerant.

He said students sometimes were made to feel uncomfortable or ignorant if they challenged their teachers on evolution. And, he said, teachers who challenge evolution are ostracized by their peers and sometimes punished professionally.

"Teachers are caught between a rock and a hard place," Calvert said. "A teacher who believes thoroughly in evolution, they're teaching kids with access to the Internet and who are going to churches where they are being given a different view."

Wednesday, April 13, 2005

Was Darwin Wrong Revisited

Loyal readers will remember that I previously recommended David Quammen's article in National Geographic, "Was Darwin Wrong?" Today the article won a National Magazine Award. An award judge wrote,
Much of the American public still fails to accept the truth of the theory of evolution. Nevertheless, National Geographic’s courageous cover story dared readers to shake off their prejudices. Firmly but tactfully, David Quammen marshals genetic data, antibiotic-resistant germs, and the anklebone of a fossil whale to build the case for Charles Darwin’s great insight, concluding that ‘the evidence for evolution is overwhelming.’

Unfortunately, only an exerpt of the article is available online.

Tuesday, April 12, 2005

As Tortoises Disappear, So Does the Theory They Inspired

Richard Cohen in the Washington Post writes that on a recent visit to the Galapagos Islands, he couldn't find the famous tortoises because they've become endangered. He sees symbolism in that.

It is odd to amble around the Galapagos and see the handiwork of evolution yet at the same time bear in mind that many Americans do not accept evolution at all. It is belittled as a mere "theory," which is a misunderstanding of the scientific term, and even in some places where it is grudgingly accepted, it is supposed to share the curriculum with creationism, as if that is an alternative theory. It is, of course, just a fancy term for the creation according to Genesis, a matter of religious belief and not scientific theory or fact. It can have its place, but not in the science curriculum.

One nitpick: The column's headline, "Backward Evolution" reinforces the mistaken belief that evolution is a process that moves forward toward an end. In truth, humans are no "more evolved" than single-celled organisms. We've all been evolving for exactly the same amount of time; we've just evolved differently.

Monday, April 11, 2005

Scientists to Boycott Evolution Hearings

I have mixed feelings about this. Members of the Kansas Academy of Sciences say they won't testify at the State Board of Education's hearings in May on the evidence for and against evolution. They say they don't want their presence to lend credibility to a ludicrous process. I've heard Holocaust survivors use the same logic to explain why they won't debate Holocaust deniers. But at the same time, I worry that many in Kansas will think scientists are afraid to stand up and be counted. I'd like to see an articulate scientist make a defense of evolution, although in this context it's almost certain that the defense would fall on deaf ears. I think the scientist who said it best was the one who said, "our state board members don't necessarily have the science backgrounds to understand what they're hearing." Reporter Josh Funk of the Wichita Eagle does a nice job with this article.

Thursday, April 07, 2005

Evolution Hall of Shame

We're going to start something new today, our Evolution Hall of Shame. The Hall won't be for run-of-the-mill creationists. I'm not interested in attacking the random family that sits around the dinner table telling the kids that God created Eve out of Adam's rib a few thousand years ago. Instead, we'll be going after people like our charter enshrinee, Dennis Baxley, a state legislator in Florida. Baxley says universities in his state are run by "dictator professors" and that students need legal protection from them. As the Independent Florida Alligator reports,

According to a legislative staff analysis of the bill, the law would give students who think their beliefs are not being respected legal standing to sue professors and universities.

Students who believe their professor is singling them out for “public ridicule” – for instance, when professors use the Socratic method to force students to explain their theories in class – would also be given the right to sue.

“Some professors say, ‘Evolution is a fact. I don’t want to hear about Intelligent Design (a creationist theory), and if you don’t like it, there’s the door,’” Baxley said, citing one example when he thought a student should sue.

Find out more about this brilliant politician at Baxley's official Web site.

Wednesday, April 06, 2005

Does a 1.77 Million-Year-Old Toothless Skull Show Compassion?

That's the conclusion of researchers who found the skull in the Republic of Georgia. The New York Times reports,

The well-preserved skull belonged to a male Homo erectus about 40 years old. All his teeth, except the left canine, were missing. The empty tooth sockets had been filled in by a regrowth of bone, the scientists said, indicating that the man had been toothless for at least two years before he died at what was then an old age. (The discoverers call him the "old man.")


Specifically, how could the man have survived that long, unable to chew the food of a mainly meat-eating society?

In interviews and the current issue of National Geographic, the paleoanthropologists said caring companions might have helped the toothless man in finding soft plant food and hammering raw meat with stone tools so he could "gum" his dinner. If so, they said, this was evidence of a kind of compassion that had been absent in the ancestral fossil record before the Neanderthals 60,000 years ago.

In the survival of the old man, Dr. David Lordkinidze said in National Geographic, "We're looking at perhaps the first sign of truly human behavior in one of our ancestors."

I remain skeptical. As fascinating a discovery as this is, I'm not convinced that it shows compassion. I think it's more likely that it shows that our ancestors were able to adapt to what would seem to be an impossible situation. That might be just as important a discovery.

Gutless University Presidents

According to Newsday, a group of university presidents gathered to talk about science education in the United States, but squirmed when asked about the most obvious issue, evolution.
[N]early everyone agreed that science in the United States is losing ground to foreign competitors. Many in attendance at the Science Coalition's yearly media roundtable, held at The Penn Club in Manhattan on Monday, cited fast-charging China and India as important new players, and bemoaned a lack of funding for basic research at home. And several attendees blasted the nation's K-12 science education as woefully inadequate.

"It stinks," Barrett said. He and several university presidents, however, dismissed suggestions that efforts to push evolution out of high school classrooms or to label it unproven may be linked to science's declining fortunes. And a question asking whether the presidents would affirm their support of the scientific theory produced evident discomfort.

Unbelievable. University presidents, who should be at the forefront of promoting the teaching of basic science, shrink from their duty when asked about evolution. Then they wonder why science education in our country is going downhill. Shameful.

Tuesday, April 05, 2005

Evolution vs. Creation = Democrat vs. Republican?

Paul Krugman writes that as Republicans become more contemptuous of free thinkers, it's only natural that scientists and academics will become more drawn to the Democratic Party. There certainly are many Republicans who believe in evolution and many Democrats who believe in creation, but there's definitely something to what Krugman says.

He references a Scientific American April Fool's Day gag in which they say they've given up in the battle for Darwinism. It doesn't appear on the magazine's Web site, but I have an excerpt below, and the whole thing is available here. (You might have to scroll down.)

In retrospect, this magazine's coverage of socalled evolution has been hideously one-sided. For decades, we published articles in every issue that endorsed the ideas of Charles Darwin and his cronies. True, the theory of common descent through natural selection has been called the unifying concept for all of biology and one of the greatest scientific ideas of all time, but that was no excuse to be fanatics about it.

Where were the answering articles presenting the powerful case for scientific creationism? Why were we so unwilling to suggest that dinosaurs lived 6,000 years ago or that a cataclysmic flood carved the Grand Canyon? Blame the scientists. They dazzled us with their fancy fossils, their radiocarbon dating and their tens of thousands of peer-reviewed journal articles. As editors, we had no business being persuaded by mountains of evidence.

Monday, April 04, 2005

Charles Darwin: The Power of Place, Part 3--Celebrity

Janet Browne's epic biography of Darwin concludes with an examination of his life after his theory of evolution by natural selection turned him into one of the world's most admired men.

A writer in 1876 asked Darwin for some personal information about himself for a book for young people about scientists. I found Darwin's responses fascinating:
Politics? -- Liberal or radical.
Health? -- Good when young -- bad for last 33 years
Temperament? -- Somewhat nervous.
Energy of body? -- Energy shown by much activity, and whilst I had health, power of resisting fatigue….An early riser in the morning.
Energy of mind? -- Shown by rigorous and long-continued work on same subject, as 20 years on the "Origin of Species" and 9 years on Cirripedia
Memory? -- Memory very bad for dates, and for learning by rote; but good in retaining a general or vague recollection of many facts.
Studiousness? -- Very studious, but not large acquirements.
Independence of Judgement? -- I think fairly independent; but I can give no instances. I gave up common religious belief almost independently from my own reflections.
Strongly marked mental peculiarities? -- Steadiness, great curiosity about facts and their meaning. Some love of the new and marvelous.
Special Talents? -- None, except for business, as evinced by keeping accounts, replies to correspondence, and investing money very well. Very methodical in all my habits.

What most separated Darwin from evolution's co-founder, Alfred Russel Wallace, was that Darwin was much more skeptical of his own hunches and careful about testing his hypotheses. (It's always hilarious to hear creationists say Darwinism is "just a theory" and "can't be tested in a lab." Darwin actually spent decades doing every experiment he could think of as he honed his theory.) As Browne writes, "Darwin regretted what he deemed Wallace's lack of caution in scientific affairs." No one could ascribe the trait to Darwin.

Darwin had a fascination with how breeding of close relatives -- in plants, animals, and humans -- affected their offspring. No doubt this was in large part because he married his own first cousin, Emma. Unfortunately, he could never persuade enough people to provide him with the detailed information necessary to study how the children of cousins fared. Questions related to that research were involved in the British census but the vast majority of citizens refused to answer. From the anecdotal evidence of his own children, some of whom had serious health problems, Darwin was concerned. But today researchers agree that there's no reason to prevent first cousins from marrying and having children.

Darwin's account of his college years will sound familiar to many: "My time was wasted, as far as the academical studies were concerned…we sometimes drank too much, with jolly singing and playing at cards afterwards."

Darwin turned completely away from religion toward the end of his life, writing in his autobiography, "The mystery of the beginning of all things is insoluble by us; and I for one must be content to remain an Agnostic." Darwin's wife, Emma, was a religious woman and horrified that her husband had no faith because it meant they couldn't spend eternity together, but Darwin called the idea that nonbelievers went to hell "a damnable doctrine."

Despite his aversion to religion, Darwin died thinking he would be buried at Downe churchyard. Instead, when other scientists learned of his death, they requested he be buried at Westminster Abbey, a few feet away from Isaac Newton, and that's where he rests to this day.

Browne's biography is one of the great achievements of the history of science. It should be read by all those who have an interest in evolution, Victorian England, or great writing.