Evolution in Oklahoma, a Road Trip: Piles and Piles of Fossils

Don’t forget the Oklahoma Evolution Road Trip, May 30-June 2. We have enough registrants that the trip is unlikely to be canceled, but there is still room! Tentative deadline is May 3, but we can accept a few more applications after that date. We just need to plan ahead about how many rooms and vehicles, and how much food, to provide. Read more about it here as well as in blog entries posted earlier (below).

One of the places we will be visiting, in our search for fossils, is Fort Washita, near Durant, Oklahoma. It is a site of great historical interest. It was built by the U.S. Army to defend the Chickasaw tribe against western tribes, whose land had been taken in order to resettle the Chickasaws from their ancestral homeland that the U.S. had confiscated. Then, in the Civil War, Ft. Washita became a Confederate fort. History and politics back then was a big mess, just as it is today, only there was a war going on right here on our American soil.

Ft. Washita was located on a hill because it allowed visibility across the prairie in order to observe the approach of understandably hostile tribes, or (later) Union soldiers. Today, most of the surrounding landscape is forested, but when the fort was built it was mostly prairie, with some scattered post oaks and bois-d’arcs. It is possible that some of the very large post oaks and bois-d’arcs that are today on fort property were alive when the fort was active. Each bois-d’arc tree appears to be several trees that have grown together. This probably occurred because the animals that originally dispersed the large fruits (e.g. mammoths and gomphotheres) have been extinct for thousands of years. The mammoths would have spread the seeds out in their dung, but since the mammoths were extinct the fruits simply landed on the ground and all the seeds began to grow in a clump.

But the main topic of interest is something that very few visitors notice when they come to the fort. I am embarrassed to admit that I did not take notice of it until recently. Most of the original buildings are made from rocks quarried from an extremely fossiliferous layer. Some of the stones appear to consist almost entirely of mollusk fossils. We’ve all seen fossils, but perhaps nothing quite like this.

So join us for the Road Trip if you can!

Evolution in Oklahoma, a Road Trip: An Encounter with Creationism

Time is running out to sign up for the Oklahoma Evolution Road Trip May 30-June 2. Information and links are available immediately below (previous blog entries). More information, and online registration, is available here.

We will also visit a couple of creationist museums on this trip. The purpose is not to create any confrontations, either between us and the creationists or within our group (since there may be some diversity of viewpoints among the attendees). What we intend to do when we visit the museums is to find out what the creationists have to say; to ask insightful questions; and then to afterwards discuss what we have seen. In particular, we will discuss some of the creationist claims that are not even clearly stated in the Bible, but appear to have been made up whole cloth by the creationists. I have met these creationists and they are not stupid; so, what IS their motivation? What makes them believe things that, to anyone outside their circles (even to most conservative Christians) seem ridiculous? Let’s talk about it.

The museums are the Creation Evidences Museum in Bokchito, Oklahoma and Carl Baugh’s dinosaur-and-human-footprint museum down in Texas (which I described in blog entries from March 2011). The Baugh museum is not worth a six hour round trip by itself but it is right next to Dinosaur Valley State Park. We will see many dinosaur footprints there, if the water is low. When I visited in Fall 2011 (see blog entries) the water was very low. We probably will not have such prime conditions on this visit, but we can see at least some dinosaur footprints and discuss what you can learn from them.

We hope to have all registrations by May 3, so we can make a decision about whether the trip will have enough people. We need 9 and we have 6.

Above all, it should be a great group of people for discussion, the kind of people you will enjoy spending a weekend with.

Evolution in Oklahoma, a Road Trip: A Dramatic Geological Past, part two.

I continue now to describe some of the geological things that we will see on the Evolution Road Trip May 30 to June 2, 2013. See here for more information.

Back in Pennsylvanian days, about 300 million years ago, sediments had been building up and turning into rock in what is now Oklahoma for over a hundred million years. Then something dramatic happened. Part of the land rose, part of it fell. Cambrian and Ordovician rocks now looked down into deep valleys. Big rocks eroded down into those valleys. Soon the valleys were filled with what was to become conglomerate rock. And such conglomerate! See the photo. The component rocks are big, and sharp-angled, both of which facts mean that the rocks did not get carried very far before being mashed together. At the scenic overlook north of Exit 47 on Interstate 35, you can see contorted layers of Ordovician limestone right next to Pennsylvanian conglomerate. Two hundred million years ago, this is where the cliff was.

Today, young couples spray-paint proclamations of love on the exposed strata. But do they have any idea what “4ever” means against the backdrop of 500 million years of geological history sometimes hidden, and sometimes exposed, in central Oklahoma?

Even in the gentlest rolling hillsides of south central Oklahoma, there are surprises. There is a very thin layer of limestone crammed with fossils (see photo). This layer is a little harder than the others and creates a shelf that I have driven past many times and never noticed. Thanks, Gordon, for pointing this and all of the preceding things out to me.

I have learned so much since my old creationist days. And I continue to learn. Most of these geological sites are near Sulphur, Oklahoma, which has a whole bunch of youth Bible camps. I am sure that one of these camps was where the Church of Christ cult of which I was a member had its summer youth meetings at which young men and women could meet and marry within the cult. (We were the branch of the C of C that rejected not only instrumental music and Sunday school but even insisted on using a single cup rather than individual cups during communion.) I never went to one. But here I am, perhaps driving right past them, in search of evidence about the evolutionary past that my erstwhile cult so vigorously denied.

Evolution in Oklahoma, a Road Trip: A Dramatic Geological Past, part one.

Breaking news: European Space Agency scientists just announced that the universe is older than previously thought: it is 6,001 years old, not 6,000. (Actually the official estimate was raised from 13.7 billion to 13.8 billion years.)

In a previous entry, I announced an Evolution Road Trip for May 30 to June 2, 2013. See here for more information. I will now tell you some reasons why I am excited about this trip. First, the geological evidence of the evolutionary past.

In the Arbuckle mountains of central Oklahoma, the sedimentary layers have been lifted up and eroded, with the result that the oldest deposits are highest in the mountains. Creationists love to point out this reverse order as evidence against evolution. But you can actually see the angles by which the layers have been uplifted.

Another thing you can see in the deposits is the difference between near-shore and deep-water (near the edge of the continental shelf) deposits. In shallow water, there is plenty of sunlight, a strong food chain, and lots of fossils; in deep water, there are fewer fossils. In addition, coarser sediments accumulate in shallow water, while finer sediments disperse into deeper water. No Flood of Noah could explain why most of the fossils are found in coarser sediments. There is a roadcut that we will visit on this trip that displays this evidence very nicely. See the photo for the Ordovician fossils found at that site. Look closely and you can see disarticulated crinoid segments, branches of bryozoans, mollusks, and even pieces of sand dollars.

At the top of the Arbuckles, you can see stromatolites. They look like lumpy rocks. But if you look closely at the photos you can see some of the splotches that used to be cyanobacterial mats; and you can see the layers inside the lumps that resemble those found in modern stromatolites.

Why are stromatolites exciting? Because a billion years ago, stromatolites were just about the highest form of life.

In the next entry, I will tell some more exciting geological stories about Oklahoma.

Note: There was an ecotour in Big Bend in March that cost $2885 for five days not counting travel, plus $450 for single accommodations. Considering this, the Oklahoma Evolution Road Trip is quite a bargain. We have a tentative registration deadline of May 3.

Evolution in Oklahoma, a Road Trip: First Announcement

I am pleased to announce that Oklahomans for Excellence in Science Education and the Oklahoma Academy of Sciences are sponsoring an evolution road trip in southern Oklahoma and northern Texas this summer. That is, so long as we get at least nine registrants. The dates are Thursday May 30 (my 56^thbirthday) to Sunday June 2. Our home base is the University of Oklahoma Biological Station on the shores of beautiful Lake Texoma. The cost will be $350 per person; for participants who want a single room, the cost is $400. You can’t beat that for a four-day weekend of outdoor science! The trip is open to anyone interested in science, regardless of background, but we particularly want to draw local pre-college science educators. If you are a schoolteacher and want to go on this trip, you can get professional development credit and (if we get enough participants or donations) a partial refund of the costs. Furthermore, if we have enough participants, we may be able to give partial refunds to everyone.

For reasons that I will explain in upcoming entries, I am pretty excited about this trip. I realize that many of my readers live far away from Oklahoma. But if you’ve never been here, you might be surprised. No, it doesn’t look like the flat dry set of a Rodgers and Hammerstein musical. It is a fascinating concatenation of ecology and geology (which is part of the reason that there is so much oil and gas here). Y’all come, y’hear?

The trip is designed especially for pre-college science instructors, although anyone with an interest in science is invited to participate. We expect to get together a group of people who will enjoy talking with one another and investigating some perhaps little-known highlights of southern Oklahoma and northern Texas—perhaps little-known even to people who live around here. I admit that, until Dr. Gordon Eggleton showed me around, I had no idea how many exciting bits of geological evidence there are in southern Oklahoma. There is a dramatic and hidden history underneath the Oklahoma dirt. Today, Oklahoma sits quietly in the middle of the North American plate. But a hundred million years ago, it was a pretty exciting place.

You can read all about it at the University of Oklahoma Biological Station website (http://www.ou.edu/uobs/evolution.html). The full brochure, with photos, is there, along with a registration form and instructions.

In upcoming blog entries, I will write about some of the things we will see on this trip. If you want to read about it how, visit the website above. If you cannot come but would like to make a donation to help defray the cost for participating schoolteachers, you can make a donation to the University of Oklahoma Foundation. Contact me at srice@se.eduif you are interested. You will be provided with a letter to acknowledge the tax-exempt status of your donation.

YouTube video interview of Dr. Vic Hutchison

I interviewed Dr. Vic Hutchison, a long-time proponent of evolution education and opponent of creationist legislation, on my YouTube channel.

Oklahoma Teachers Evolution Workshop, Part Seven

As the Teachers' Evolution Workshop sponsored by Oklahomans for Excellence in Science Education drew to a close on October 9, we had presentations and discussions by high school teachers about how to teach evolution, usually in interesting laboratory settings.

Andrea Blair, high school teacher in Broken Arrow, Oklahoma, and a graduate student at the University of Tulsa (where she spends time studying the anatomical structure of amphibians), told the participants about some of the lab activities she has devised or adapted. Some were versions of the natural selection simulations that have been used in many classes for decades; for example, to simulate natural selection of light vs. dark moths against light vs. dark bark, based on the twentieth-century studies by H. B. D. Kettlewell. But the greatest amount of discussion came in response to Andrea's investigation of radiometric dating. Students begin with a box of coins, all heads-up, which represent radioactive atoms. Then the students shake the box just once, count and remove the tails-up, which represent atoms that decayed. The students repeat this over and over, and generate a graph of radiometric decay. But they do so by stimulating a random process (actually a quantum process). I, for one, have never heard about this activity from anyone else.

Andrea also described how to use different colors of beans to represent alleles in a population. Students randomly draw pairs of beans that represent diploid individuals in a population. Then, natural selection can be simulated on the simulated diploids. The advantage of this activity is that students can see the effect of natural selection not on phenotypes but on allele frequencies in a population. This activity can be modified to simulate genetic drift and founder effect.

One thing that Andrea emphasized is that these activities are cheap and easy. You don't need a budget for prepared teaching materials or for computer simulation software. Best of all, students are learning about the processes of evolution, without feeling like "evolution" is being pressed upon them.

And with this, the workshop ended. The participants were, we hope, inspired and equipped to teach evolution in creative ways and to deal constructively with inevitable conflicts. The setting, the University of Oklahoma Biological Station on the shore of Lake Texoma, was restful and beautiful.

Oklahoma Evolution Workshop, Part Six

Early on Sunday morning, the clouds blew away. The Teachers' Evolution Workshop, sponsored by Oklahomans for Excellence in Science Education, began with a presentation by Bob Melton, curriculum specialist for the Putnam City schools. Both Oklahoma and Texas have repeatedly received a grade of "F" from the Fordham Foundation for science education, because the Oklahoma state standards (and until recently those in Texas also) do not include the word "evolution." The Fordham Foundation has actually indicated that this is the reason for their low rating. However, Bob pointed out, all of the components of evolutionary science (such as natural selection and change in populations) are present. This is simply because state legislators and administrators hate evolution but do not know what it is, so that in the absence of the actual word these state officials do not realize that evolutionary concepts are being taught. Meanwhile, in what I consider a supreme irony, the very same government officials who refuse to include evolution in the state education standards have turned around and criticized science teachers for doing such a bad job and getting Oklahoma an F.

Bob reviewed the legal cases which, in every case, confirmed that evolution, and not creationism (including intelligent design), must be taught in biology courses. In some cases, some teachers have claimed that their First Amendment right by requiring them to teach evolution, but the courts have not agreed with these teachers. Moreover, schools may limit the extent to which students can disrupt classes, nor opt out of sections of classes, because of religious objections. This would be like saying, "For religious reasons, we do not want our children to learn about the Civil War in American history class." On the other hand, science instructors cannot ridicule religious beliefs in class. If teachers encounter resistance from administrators to teaching evolution, they can take some comfort in the fact that major scientific and educational societies (such as National Association of Biology Teachers and American Association for the Advancement of Science) have issued statements in support of teaching evolution.

It is doubtful, however, that any teachers in Oklahoma and Texas would have time to fight local officials for the right to teach evolution. One of our participants is a high school teacher who has to, on a Sunday, to grade 454 papers, after her three-hour return drive from this workshop. It is, perhaps, better to avoid conflict as much as possible. But one way to do this, modeled by Kansas high school teacher Ken Bingman, is to get the students to investigate evolution for themselves, rather than to just tell them the scientific truth.

Bob also got the participants to think of new ways to make teaching more fun, for example with songs such as "It's a Long Ways from Amphioxus."

The second presentation was by Dr. Joseph Maness, a biology professor at Southwestern Oklahoma State University. Jody gave the participants ideas about how to deal with the religion/evolution conflict. In Oklahoma, many students have been raised to believe that if they accept evolution, they will literally go to hell. What should we do? We can get some help from the American Association for the Advancement of Science's Dialogue on Science, Ethics, and Religion (DoSER). Their book The Evolution Dialogues explains that students do not need to choose between science and faith. For one thing, there is not just two positions (creation vs. evolution) but a whole continuum of viewpoints, as I mentioned in an earlier blog. There is a whole continuum of views. Eugenie Scott of the National Center for Science Education has published a diagram of this continuum, which was modified from one developed by a Christian geologist, Davis Young, who taught at Calvin College in Michigan.

While I admit that ther does not have to be a conflict between science and faith, I think we should be honest with students about what I call the "vast gulf" between science and religion, which I have begun and will continue to discuss in entries to this blog. Therefore, science and religion can be reconciled, but you have to decide to make them reconcile. For example, DoSER claims that science and religion both have "reason" as a shared value. Of course, this is not true of many religions, even in America. In most cases, the process of reconciliation has resulted from the advance of science and retreat of religion. Jody told us that in Biblical times, "faith" meant "trust" rather than "doctrine." I admit that the "trust" definition of faith makes the "vast gulf" between science and religion not quite as wide as I had indicated in my earlier blog entry. Nevertheless, most people today equate "faith" with "doctrine" handed down by religious leaders.

Several conference participants expressed the view that an overview of the potential compatibilities between science and religion would have been a good way to begin, not end, the workshop. These participants, religious beleivers, wondered if their faith was being attacked at the workshop, when to their surprise this was not the case.

Oklahoma Evolution Workshop, Part Five

For the late afternoon and evening sessions, the workshop focused on educational and religious issues related to evolution.

Dr. Mary Kay Johnston is a new young professor at Concordia University in Austin TX, which is associated with the Lutheran Church. That is, the Missouri Synod of the Lutheran Church, which officially endorses young-earth creationism but tolerates some diversity of opinions within the academy. She has not experienced trouble from her colleagues or church leaders for teaching evolution, but does have to deal with students coming to college with misconceptions of and hostility toward evolution. This quickly turned into a lively discussion about how to deal with religious issues popping up in science classes.

To avoid some of these problems, Dr. Johnston suggested, we could do some of the following things. For example, talk with students about what science really is. Also, let them know how evolution works before you begin talking with them about the products of evolution, especially humans. And use examples of evolution that are less likely to elicit a negative reaction; students (and their parents and preachers) are unlikely to get bent out of shape over the evolution of diatoms. You don't even have to call it evolution at first. Dr. Johnston encouraged us to deal with Intelligent Design, and to point out the flaws in its fundamental argument: that the parts of a complex system cannot work by themselves. The creationists' favorite example is the bacterial flagellum; but the basis of the flagellum is the same as that of a secretory apparatus.

Rich Broughton also told participants about some excellent teaching resources that are available online, such as Understanding Evolution, the National Center for Science Education, the Howard Hughes Medical Institute Cool Science site, and the Talk Origins Archive.

You can't get a lively group like this to not keep talking about religion-science issues. Dinner conversations got serious, in a constructive and friendly way. Those of us involved in this discussion got to know and appreciate each other more, in my view.

For the evening session, Dr. Victor Hutchison, retired from a distinguished professorship at the University of Oklahoma, told us about how creationism and intelligent design are not science, but are politics and religion using science as a disguise, and demonstrated this to us by quotations from the creationists. For example, to Phillip Johnson, the removal of evolution will be the "salvation of western civilization." This is clearly a conflict between science and religion, fueled from the religion side. The militant atheists fuel the attack from the atheist side, especially the "Gnu Atheists." I had never heard this term before; this group of atheists invented the term for themselves. The gnu atheists attack "accommodationists" who try to at least defuse some of the religious conflict over evolution. Meanwhile, many churches such as the Catholic Church (under Pope John Paul II) accept the science of evolution, and some scientists (such as Thodosius Dobzhansky, one of the founders of evolutionary science) have been religious. Dr. Hutchison pointed out that there are not just two views of creation vs. evolution; there is a whole range of views.

There is also a problem between intelligent design and science: if you simply say, regarding anything that you think is complex, "the Intelligent Designer created it," this brings scientific inquiry to and end. The creator made it; end of story. Not surprisingly, the intelligent-design creationists have not published their own scientific research. And intelligent design is clearly motivated by politics. When Judge John Jones ruled against the creationists in the Dover trial, Republicans were quick to attack him, even though he was a Republican who had been endorsed by Rick Santorum and appointed by George W. Bush.

The intelligent design side is sometimes dishonest, Vic told us. The creationists, going into the 2005 Dover trial, submitted a pile of scientific papers that they claimed supported their view. When the defenders of evolution contacted the authors, they indicated that the creationists had misconstrued the papers to mean something that contradicted their scientific conclusions.

Vic updated us about the recent history of creationist legislative bills in Oklahoma, which narrowly failed, and only because Oklahomans who cared about science education contacted the legislators. He spoke over an hour with incredible energy, even as he enters his ninth decade. Who can follow him, when he finally becomes too tired to continue his work? There are several of us on the Board of Oklahomans for Excellence in Science Education, sponsor of this workshop, who can try, but it will take all of us to keep his work going.

Oklahoma Evolution Workshop, Part Four

The evolution workshop for Oklahoma teachers continued after lunch. I had the first session. I began by advertising my own website, where you can find essays and photographs, as well as copies of scholarly articles  I have written. It has links to my YouTube channel and to this evolution blog.

Then I began with the story of the Ghosts of Evolution. (I have a recent YouTube video where Darwin discusses this subject.) I held up a big, sticky, green fruit of Maclura pomifera, known as bois d'arc, Osage orange, or horse-apple. The native range of this tree includes Oklahoma. I modeled the kind of questions that they can ask their students. Why do some plants produce juicy sweet fruits? Animals eat them, swallowing the seeds and transporting them to a new location. This is useful to the plant only if the animal swallows undamaged seeds, as we do with strawberry or kiwi seeds, or as raccoons do with persimmon seeds. With their finicky fingers, some raccoons could pick out the persimmon seeds, but this would waste valuable time, during which other raccoons would eat up all the fruits. The concept that students might grasp is coevolution. In this case, juicy fruits evolved in response to animals that eat them and disperse their seeds.

But what eats big, sticky bois d'arc fruits? In Oklahoma, someone will always say, horses. In other parts of the country, nobody may have any idea. But modern horses are not native to North America. There were native horses in North America at the end of the last ice age, but they have become extinct. Perhaps at the end of the last ice age, there were large animals (horses, mammoths, mastodons, gomphotheres, etc.) that ate bois d'arc fruits, but today, there are no native animals that eat them. Thousands of years ago, there was a coevolutionary waltz between bois d'arcs and gomphotheres; today, the bois d'arc is doing a waltz with no partner.

We went outside, into the cold wind. The temperature has dropped 50 degrees in two days. If you want to get kids outside and still teach them about evolution, just take them to an oak tree and ask them what they know about oak trees. The wood is strong. The trees live a long time. Acorns are large, as are the seedlings that emerge from them. Now, think about what kind of environment would benefit trees that have these characteristics. In an old, stable forest, large seeds and large seedlings would be better able to compete with the dense populations of plants that are already there. They invest for the long term in strong wood. Then take the kids to a cottonwood tree. Cottonwoods produce cheap wood and do not live very long. Their seeds are numerous and small. These characteristics make sense for trees that live near rivers, where they have a lot of water but also face a great risk of being destroyed in a flood. It would make no sense for a cottonwood to invest in wood that will last for centuries, since a cottonwood tree would probably get killed in a century or less. This may help students to understand that evolution does not always produce the same "superior" set of adaptations; the "superior" traits for a tree in an old, stable forest are different from those in a young, frequently-disturbed, floodplain forest.

Then Dr. Cecil Lewis had a second session, this time devoted to his specialty: the evolutionary and medical genetics of humans. He explained how population genetics works. A large, old population that has been large for a long time may have a great deal of genetic variation, including a lot of rare variants. Large populations can lose genetic variation if they become small--that is, they go through a population bottleneck. Small populations can lose genetic variation just by chance. If the population then grows rapidly, it retains the genetic makeup that it had while it was small. That is, a newly-large population will have no more genetic variability than it did when it was small. If you find a population that is large but has low genetic variability, this probably means that there was a recent genetic bottleneck. This appears to have happened in the human species. The entire human species, all seven billion of us, has the same amount of genetic variation that one would expect from a mammal population with only twenty thousand individuals. This suggests that (perhaps 70,000 years ago) our species had a brush with extinction--there may have been, at that time, only about twenty thousand of us.

You can make a closer examination of the genetics of human groups. The greatest genetic variation is in Africa. The genetic variation in the Middle East is a subset of African genes. The genetic variation in Europe is a subset of Middle Eastern genes; Asians are a separate subset. North American native genetic variation is a subset of Asian genes; South American native genetic variation is a subset of North American native genes. Each time a migration occurs, only a subset of people leave home, therefore some genes get left behind. Human genes, therefore, are an invisible record of the pattern of human migrations during the last 200,000 years.

Some human genetic patterns have resulted from natural selection. Lewis gave an example: the ALDH2-2 gene, the gene that codes for alcohol dehydrogenase. One variant of this gene is much more common in Asians than in anyone else. The Asian variant is the reason that Asians generally have a lower tolerance of alcohol than other people. However, since refiend alcohol is a recent invention, the Asian variant of the gene was probably selected by exposure to pathogens.

Oklahoma Evolution Workshop, Part Three

The workshop sponsored by Oklahomans for Excellence in Science Education has brought together high school teachers and college faculty from Oklahoma and Texas. It began Friday night, October 5, and continues this morning. A few minutes ago, I blogged about the first two presentations, both of which addressed the scientific way of knowing about the world.

Now, Dr. Richard Broughton, a zoologist at the University of Oklahoma, is discussing how to interpret phylogenetic trees and how the phylogenetic way of thinking has changed our view of life. A millennium ago, scholars all believed that everything from the simplest animals to humans formed a scale of being from lower to higher. After Darwin, most scientists accepted that all organisms were part of a tree of life, rooted in a common ancestor--but they still accepted humans as the top of the tree, as if this is what the tree was meant to produce. But, when you think about real trees, you would never think that the top twig (if you can even identify it) is what the tree is all about. Modern evolutionary thinking identifies all species as being equally "evolved," all of them (us) being twigs on the tree.

Phylogenetic thinking has gotten scientists to think in terms of evolutionary branch points. Mammals, for example, all share a common ancestor (phylogenetic branch point), while all birds share a common (dinosaur) ancestor. Further back in time, birds and mammals shared a common vertebrate ancestor. This ancestor had the same limb bone pattern found in birds and humans, therefore this pattern is homologous. But this ancestor did not fly; bat and bird wings are, therefore, analogous--they evolved separately, despite their similar appearance. Phylogenetic trees can be based on physical characteristics (bones, wings, etc.) or on DNA data.
Rich had the participants figure out a phylogenetic tree based on a set of xerox copies; the ones that have the same shared derived characters (smudges made in copying) have a more recent common ancestor than the other. Therefore phylogenetic analysis can be used to figure out the pedigree of, for example, ancient Biblical manuscripts.

One of the best pieces of genetic evidence for a shared ancestry of chimps and humans is human chromosome 2. The genes of human chromosome 2 line up with those of two chimp chromosomes, but one of them is reversed. Human chromosome 2 has nonfunctional telomeres in the middle, and a nonfunctional centromere--which exactly fits what you would expect if two ancestral chromosomes fused together end to end in the human lineage, but not in chimps. But, as Rich emphasized, there are a lot of other pieces of genetic evidence, including shared noncoding DNA inherited from a shared ancestor. You can construct a phylogenetic tree of primates based on nothing but ERV (endogenous retroviruses; dead viruses that got stuck in the chromosomes) and it matches the phylogenetic trees constructed on the basis of completely different sets of data. The recent availability of whole-genome sequencing has allowed many new examples to be found. A group discussion revealed that no coherent explanations have been offered for these genetic patterns by creationists, who reject shared ancestry.

Even something as easy to understand as vitamin C provides evidence of evolutionary ancestry. The bodies of most mammals can make vitamin C, but primates cannot. Primates must get vitamin C from their food. By chance, the ancestors of mammals lost the ability to produce vitamin C, but it didn't matter, because they ate lots of fruit. We still have the gene for making vitamin C, but it sits unused in our chromosomes.

Scientists study species such as fruit flies--why? Some politicians think this is ridiculous, and boldly say so. But we share a lot of genes with fruit flies, and we can learn a lot about these genes by studying fruit flies. It is evolution that makes sense of this pattern. It confirms what Darwin said, even though he could not have imagined any of these molecular patterns.

Oklahoma Evolution Workshop, Part Two. What is Science?

The workshop sponsored by Oklahomans for Excellence in Science Education has brought together high school teachers and college faculty from Oklahoma and Texas. It began Friday night, October 5, and continues this morning.

The first presenter is Dr. Cecil Lewis, an anthropologist at the University of Oklahoma who uses DNA studies to illuminate human evolutionary history. His topic is the nature of science. Creative expression, critical thinking, writing, and math: if you can do these things, he says, you can do science. Science does not destroy the beauty of the natural world by dissecting it, but helps us to appreciate its beauty more deeply because we understand how it works. Reflecting the ideas of Lee Smolin in The Life of the Cosmos, Lewis said that when we look up into the night sky, we see not just pretty stars but the crucibles in which the elements of which life is made were created.

Students are sometimes surprised that we do not know the answers to everything. (I, for one, have gotten comments from students who didn't like me saying "I don't know.") But that is science: it is always investigating new questions, often replacing old ideas with new ones. And there are always things that we will probably never know. Both scientific and religious suppositions can, by trying to quickly fill in the gaps of our understanding, stifle our quest for understanding. Not understanding something is not necessarily a deficit; it can be an opportunity. He pointed out that we should be careful to distinguish such things as scientific fact and scientific theory: the theory explains the facts. The principles of scientific investigation, which many people think they do not understand, are not all that different from the principles of criminal investigation. We have to accept the fact that we all, scientists or not, are susceptible to bias and error.

We got into a detailed discussion of the differences among theory, hypothesis, organizing principles, coalescence, multiple tiers of theory, and even faith, which was valuable for us but which, I suspect we all agreed, we should not necessarily use in our classroom; the students would tune us out and think that we were just being "theoretical," without knowing what they meant by this. Sort of like the cast of Big Bang Theory. I did not dare throw another term into the mix, one that I consider important: consilience. (Evolution has consilience because it is a conclusion that can be arrived at my numerous separate lines of reasoning based on independent sets of facts.)

I offered a summary of my own during the discussion: We are all like cows, prone to wander away from the path of truth; science is a yoke that keeps us on path, while pulling the cart of knowledge forward. I'm not sure if this means anything, but it is a nice sound bite. I used it in the "scientific mthod" entry in my encyclopedias.

What we certainly do not want to do is to create the impression that science has all the answers. In the minds of our students, we scientists will lose the battle of authority if we try to compete with religion. God, even if God does not exist, will always overwhelm the greatest scientist.

So, how can we bring scientific thinking into the classroom? Certainly not by talking about the philosophy of science. Instead, according to Julie Angle (a science education professor at Oklahoma State University), we should do it by having classes do hands-on activities that promote problem-solving skills. "Engage their minds!" she said. She used the "cube activity:" by looking at numbers and colors and fonts on five sides of a cube, we can infer what is on the sixth side--that is, if there is anything on the sixth side. This activity seems simplistic, but exercises scientific thought well enough that the National Academy of Sciences included it in their book Teaching about Evolution and the Nature of Science.

Julie's second activity was one I'd never seen before: the "check it out" module developed at Indiana University. Just from looking at a few checks from an envelope, students can try to reconstruct a story line about what is happening. It is the kind of reasoning that Perry Mason would use to figure out who the murderer is. The participants found out it isn't quite as easy as you might think, because each group of participants drew out a different subset of checks upon which to base their tentative hypotheses. It is also possible that some of the checks were irrelevant to the story line. When scientists gather observations, we cannot be sure that all of the observations will be useful. When a writer puts a whole lot of irrelevant information in a novel to mislead the reader--as Arturo Perez-Reverte did in Club Dumas--I find it infuriating; but nature does it all the time. From these activities, we experienced the fact that scientific reasoning emerges from reasoning abilities our prehistoric ancestors used to, for example, track animals.

In Julie's final activity, the participants looked at fossilized footprints to reconstruct the story of how the footprints formed. At first, they have incomplete information, and modify their hypotheses as more evidence becomes available.

As Shawn Lawrence Otto explained in Fool Me Twice, the attacks on evolution and other major scientific issues by the general public are not due to a deficit of knowledge, but due to attitudes. By getting students to do some simple scientific hypothesis-testing, we can open their minds to science as a way of thinking. It might be worth the time, even in a course (such as general biology) already brimful of information.

Oklahoma Teachers Evolution Workshop Begins

Tonight, the eighth annual Teachers Evolution Workshop in Oklahoma begins. It is sponsored by Oklahomans for Excellence in Science Education. We are meeting at the University of Oklahoma Biological Station on the north shore of Lake Texoma near Durant. The meeting has been organized by Dr. Richard Broughton of the University of Oklahoma. The participants are teachers and graduate students from Oklahoma and Texas. The first presenter is Dr. Ola Fincke of the University of Oklahoma. She is most famous for studying the sexual selection of damselflies in distress.

Dr. Fincke is telling us about how to incorporate evolutionary concepts into high school biology teaching in such a way that they are less likely to resist it. She suggests that we get the students to ask questions about why organisms have the adaptations that they do: why do so many insects have camouflage? Why do some flowers stink? Students can figure out answers to these questions. Throughout her session, Dr. Fincke used the question-and-discussion technique, to show that it can work. Sometimes the discussion got a little confused, but not for long; but that is a risk you have to take to allow students to investigate and understand for themselves. The principles of phylogeny can be illustrated by genealogical patterns, which the students already understand. A frog is more closely related to a human than to a fish because frogs and humans share a more recent common ancestor, just as siblings share a more recent common ancestor with one another than with a cousin.

Evolution is both fact and theory: the fact that it happens, and the theory that explains how it happens. It happens by natural selection. Humans have used a type of applied selection to produce many varieties of crops and livestock and pets. Students may be surprised to realize that natural selection, as proposed by Darwin and Wallace, is a common-sense principle: how could it not happen? Natural selection is not chance; therefore, evolution is not caused by "random chance." Natural selection is undirected, but is not random!

The fact of evolution is demonstrated by such things as the vestigial hips in whales, which have no hind legs. It is also demonstrated by the fact that it happens all the time around us: new strains of HIV evolve within the bodies of HIV-positive people. Why do icefish in Antarctic waters, which have no hemoglobin in their blood, still have hemoglobin genes--this can be explained only by evolutionary ancestry. Geneticists can take a gene that stimulates eye production from a mouse, and swap it out in place of the fly eye-production gene, and it still works in the fly--this is an experiment that confirms shared ancestry.

In the discussion that followed, we talked about whether teachers should call evolution what it is. This opened up a big political can of worms, which created an open argument among the instructors to which there was no resolution. But, as Dr. Fincke showed, you can teach evolution through common sense and evidence.