Saturday, December 31, 2011

Natural Selection of Economic Models

We are now closing the year 2011, which has been remarkably like 2010. Continued global warming, continued opposition to the teaching of evolution and global warming, continued economic uncertainty, and another year with a Congress that considers its sole function to be partisan strife.

But one of these years, enormous changes will have to come. As economist Kenneth Boulding pointed out decades ago, and as environmental entrepreneur Paul Gilding has pointed out in his 2011 book The Great Disruption, growth cannot continue forever in a finite world. Gilding says that our current economic system will collapse, since it depends totally on economic growth. It will have to be replaced by an equilibrium economy. Gilding points out that this inevitable transition will not occur smoothly or gradually. At some point, a critical mass of people will realize that, in a finite world in which global warming will disrupt our lives, we have to change. Many of us realize this already; and we are a rapidly growing minority. The change will be disruptive, since entire industries (such as coal and oil) have refused to admit that we are about to collide with natural ecological limits; they will fight to keep people not just using but wasting natural resources. Big corporations will continue to demand government bailouts for their own business mistakes. They preach capitalism but demand socialism. The resulting chaos, in a world with natural disasters and scarce food, will not be pretty. One of these years—it might be 2012—will make 2011 seem like a very uneventful year.

Gilding says that we will emerge from the chaos with a new and sustainable economic system. He says that it is the next stage of human evolution. When I first read this, I assumed that he simply did not know what evolution was. But after I had read more of his book, I could see that he may be right. He did not mean biological evolution. He meant cultural evolution—some memes are propagated more than others. I have written about this process in books. But after reading Gilding’s book, I found a new example of cultural evolution: the economy.

The economy consists of many memes, which include: We have to keep growing to avoid collapse; we have to acquire ever more stuff in order to be happy; since the economy will always grow, we can put ourselves deeply into debt; ecological issues are something that we can take care of someday when we are all rich. These are the old, destructive memes that have brought our economy to the brink of disaster. But there are other economic memes: Our economy can be sustainable; happiness does not require lots of stuff; we can live within our means; we need to fit our economy into ecological limits now. There are millions of people (not enough millions) who believe this second set of memes; and there are hundreds of companies that abide by them. That is, in the world of economic memes, there is diversity.

And then along comes catastrophic natural selection: an economic collapse. If we were all hypnotized by consumerism, then this collapse would mean extinction. However, natural selection will in this case favor the sustainability memes, which already constitute a significant minority of the memetic variation in our population. Yes, there will be an enormous collapse; but many individuals and corporations are at least partly ready for it. There are, for example, hundreds of alternative energy companies ready to fill the void that will be left by the downfall of the petroleum industry.

This sounds like good news. I wish I could believe it, but I believe that political conservatives will prevent us from making enough changes to survive the coming collapse; they will suppress the solutions. The CEOs of financial corporations, for example, want to keep us in debt rather than to let us live without owing them money. Like a bunch of walnut trees suppressing other plant species by poisoning the forest with juglones (a process known as allelopathy), these CEOs are suppressing the sustainability memes. But they cannot wipe them out. At some point, a sustainable world may emerge, by the process of cultural evolution.

On this last day of the year, we sigh in relief that we have not yet fallen into disaster. We look forward to a new year in which, if we are lucky, the memes of sustainability will have a chance to make progress, and in which the collapse will not yet occur. If we are lucky.

Friday, December 23, 2011

Altruism: The Third Alternative for Ecology and Evolution

Consider the following to be my holiday message to you. It is adapted from an essay I wrote for my website.

I recently read a book entitled The Penguin and the Leviathan, by Yochai Benkler, a leading scholar in business research. I have read many books about altruism, many of them by scientists such as Frans deWaal (The Age of Empathy), Dacher Keltner (Born to Be Good), and Martin Nowak (Super Cooperators). These books repeatedly make the point that individuals within animal species, individual humans, and businesses can profit from being nice and generous to others. Altruism, rather than violent competition, is the most important component of “the law of the jungle.” Just ask any of the chimps that deWaal has studied. The way to the top is primarily through cooperation, not violent competition. Even apes understand this. Benkler’s book is published by Crown Business, a division of a major New York publisher. Its intended audience is not science buffs but business leaders. In the title, the Penguin is Tux, the icon of Linux, whose business model is cooperation rather than top-down command, and the Leviathan is the cynical view of life presented centuries ago by Thomas Hobbes.

Benkler, though not a scientist, has done a very good job of summarizing the evolutionary science of altruism. But the thing that opened my eyes the most was that Benkler presented altruism as a third alternative for how a society could operate. The other two ways are state control and free market. We usually think that these are our only two choices. But, as Benkler explains, this is not true.

Both state control (as exemplified by dictators on the political right or the political left) and free market economics operate from the assumption that humans are fundamentally selfish. State control attempts to force people to not be selfish. The free market tries to capitalize upon those utterly selfish economic machines known as humans. But Benkler points out that altruism is a fundamental instinct of the human mind. As Michael Shermer said, it feels good to be good; humans enjoy being altruistic. Altruism motivates much of what we do.

Our only hope, from Benkler’s viewpoint, is to build our society and economic system in a way that facilitates altruism. Governments should not try to solve all social and economic problems by law and by creating big agencies; governments should be (in my words) conduits of the altruism that already exists in people’s minds. Governments should be altruism enablers. Similarly businesses should embrace altruism, appealing to their customers’ instincts to want to create a better world for everybody. Customers are selfish, but also altruistic. Customers are increasingly offended by corporations that display conspicuous selfishness; that assume the customers are merely selfish; or that use little greenwashing gimmicks to make themselves look environmentally friendly or socially altruistic. We customers are not stupid, nor are we totally selfish. We are (some of us more than others) partly altruistic and we expect our governments and businesses to also be altruistic.

Benkler makes the point that right now, when dictatorships are falling and the free market has proven ineffective enough that it has shaken the very faith of Alan Greenspan himself, is the time when altruism has a chance to influence the very structure of the economy and government. Governments and business CEOs have been good only at spending money, with disastrous consequences that nobody can ignore any longer.

Altruism, perhaps the greatest gift of evolution, is also the only way to solve our environmental problems. Neither of the other alternatives, government fiat or the profit motive by itself, have significantly deflected our worldwide momentum toward ecological disaster.

Joy to the world? Altruism? Maybe.

Friday, December 16, 2011

A Statement of Respect

This morning, my colleague from graduate school, Art Zangerl, died after a long battle with cancer. He personified what it means to be a dedicated scientist. He had a zeal for using science to understand not just his own area of study (coevolution of insects and herbivores) but the whole human experience of the world. I remember him doing research while we were still graduate students; he would nearly run from one room to another, carrying electrophoresis gels. This was a new technology back then, and Art studied the PGI locus to understand population variability in weeds. He was never afraid to embrace new technology, while not discarding the old. I remember him sitting at a calculator that was the size of a small table, a Wang, which used a cassette tape to store its calculation. This was long after calculators were hand-held. He also had a passion for studying things (such as invasive weeds) that had an important effect on the human economy. He worked with May Berenbaum, who may be the most famous entomologist in the world. Among other things, they studied photophytodermatitis (or is it phytophotodermatitis?) caused by wild parsnips. Everyone respected, admired, and loved Art.

In the photo posted above, taken about 1981, Art (behind the equipment) and Mark Boudreau (who is now a professor of sustainable agriculture) were using an infra-red gas analyzer to measure photosynthesis. You can see that it was a home-made apparatus, and Art was a major contributor to its construction.

Art’s wife posted his final message online right after his passing. One of the things that he regretted seeing in our society today was the large number of people who attack science general and evolution in particular in the name of religion. He wrote, “Evolution is like a magic key. Once you understand it, really understand it, so much becomes clear.” He said that evolution helps us understand the darker side of human nature, but also what he called the social side, such as altruism. Although evolution has made us a species capable of hatred, we are also a species that can fight against hatred and oppression. Art particularly admired the work of the Southern Poverty Law Center.

I hope that I can leave behind as good a legacy of honest intellectual inquiry and genuine human warmth as Art Zangerl.

Friday, December 9, 2011

Staying on Message

This is just a brief note to say that, in this blog, I will attempt to stay “on message” about evolutionary science and related subjects. Inevitably this will take me often into politics and religion, which would not happen if politicians and religious leaders would just focus on their own fields without trying to use evolution as a whipping boy to pick up votes and donations.

I assumed that other evolution blogs would do the same. I was disappointed to see, in August 2011, that Jerry Coyne’s blog was taken up by lots of photos of impressive architecture around St. Petersburg, and even the long-running and respected blog Panda’s Thumb is frequently used for just posting pretty sunset photos. P. Z. Myers’ Pharyngula blog also seems to wander around quite a bit. Nothing wrong with these things, and Jerry Coyne is one of the leaders of modern evolutionary thought, but my intention is to make this blog a useful place for you to learn about evolution. I hope you send your friends to my blog for useful information about evolution. See also my website, where I have a section with lots of photos, but rather than just being pretty sunset photos, they are photos with stories to tell about evolution and biodiversity.

Friday, December 2, 2011

So the Appendix Isn’t Worthless After All

The vermiform (“wormlike”) appendix is an extension of the human large intestine. It is homologous to a part of the caecum of other mammals. Humans (and cats) are among the most finicky eaters in the mammal world. Humans use intelligence to choose foods that are safe and nutritious to eat, at least we did so under the prehistoric circumstances in which our bodies evolved. But most mammals, particularly herbivores and omnivores, just eat stuff, and rely on their intestines to process the food. Dogs just gobble things down. As for cats, which are not necessarily any more intelligent than dogs, I do not know why they are finicky. (One of our cats once ate a ribbon off of a Christmas tree, not an impressive example of intelligence.) An important part of intestinal food processing in most mammals is the caecum, in which bacteria break down many otherwise indigestible food materials. Humans have big brains and small caecums; most mammals have smaller brains and larger caecums; once again, I have no explanation for cats. In humans, part of the caecum has degenerated into the appendix, which really does look like a worm, and is not large enough for any significant amount of food to enter. It is a dead end tunnel off the side of the intestine.

The human vermiform appendix is largely considered to be vestigial and worthless. But it turns out to not be entirely worthless. Sometimes disease bacteria multiply in your intestine, and drive out the good bacteria that normally live there. Then the disease bacteria eventually die away, if you are lucky. Eventually the good bacteria return to their intestinal home. But where do they come from? Apparently, many of the good bacteria hide in the little appendix corridor, and emerge after the bacterial war is over. The appendix is therefore a refuge for good bacteria. This is particularly important for modern people who take oral antibiotics, which devastate the bacterial populations in the main part of the intestine, but not on the appendix.

But even though the appendix is not worthless, it is still vestigial. It is reduced in size and function compared to our mammalian ancestors. In humans it no longer serves a digestive function. It has degenerated over evolutionary time, though not far enough to have become worthless. It remains today, as in Darwin’s day, an excellent example of a vestigial organ.

Don't forget to check out my YouTube channel.

Friday, November 18, 2011

The Garden of Eden in Ancient Oceans

There never was a Garden of Eden, but there was, perhaps, a Garden of Ediacara. (See the book by Mark McMenamin by this title.) Ediacaran organisms (named after the place in Australia where their fossils were first recognized) were blob-like creatures that lived in the sea about 600 million years ago. In this innocent garden, there were no predators. As soon as the predators evolved, it seems that the Ediacarans all got eaten.

It is easy to see what an attraction it is to an animal to eat other animals instead of eating plants. Animal flesh is much more nutritious than leaf tissues. Leaf tissues have a lot of water and fiber, while animal flesh is a highly concentrated source of protein and fat—even more so than seeds, which are rare compared to leaves. One might even say that many herbivores would be carnivores if they could. Live squirrels sometimes nibble on roadkill squirrels, and deer sometimes eat captive chicks. Natural selection has favored squirrels that are really good at finding and eating nuts and deer that are good at browsing. They are not very good predators. But if a nice dinner of meat is presented to them, who are they to turn it down? Nonhuman vegetarians, like most human vegetarians, are tempted by meat.

Predators are usually swift, intelligent, and have good eyesight. Each of these adaptations allows them to find and catch prey more effectively. It is true that prey would benefit from having these adaptations as well. Swiftness, intelligence, and sharp eyesight would allow prey animals to escape predators. But in most cases, predators are superior in these respects, and natural selection has favored prey that can see only well enough, and are only smart and fast enough, to hide. By spending less of their time and energy on defense against predators, the prey animals that survive animals can produce more offspring and find more food. Predators generally produce fewer offspring than prey animals do. Sometimes, prey animals are poisonous, and predators evolve the ability to tolerate the poisons.

Prey defenses do not have to be perfect. Some defenses appear to be almost perfect: some mantises look just like sticks or leaves, enough to fool even naturalists walking through the woods. But even a little bit of camouflage is better than none at all. I saw a cartoon once in which a lion told a zebra, “You call that camouflage?” Black stripes on white (or white on black, I forget which) honestly do not look like the grasses of the African savanna. Except, that is, at nightfall, which is when the lions are most active. Zebras are blatantly obvious in the middle of the day, but that is when the lions are dozing. Predator adaptations need not be perfect either. As I write, our cat seems unable to tell the difference between my computer mouse and a real one. Natural selection has not favored the evolution of sufficient intelligence in cats to allow them to distinguish an actual mouse from other objects. Even though computer mice have not been part of the evolutionary experience of cats, an extremely intelligent cat should be able to tell that a bright green object without legs is not a mouse. But cats, such as the hundred million feral cats in the United States, are intelligent enough for their own purposes. To have greater intelligence, a bigger brain, would be a waste of resources for them.

Some prey animals have social defenses. They form large herds in which each animal looks out for the safety of the others, to a certain extent. Lions can subdue an individual zebra or wildebeest, but when confronted by a flood of hooves and confusing black and white stripes, where to begin?

The Garden of Eden was, by tradition, filled with vegetarian animals. Vegetarian tigers and lions. As you can see, such a Garden could not have persisted for very long; inevitably, some of the animals would have evolved into predators. There will never be a world in which, as in the vision of the prophet Isaiah, the lion lies down with the lamb. The natural world is not like the Bambi movie, with Friend Owl imparting wisdom to little Thumper. In the real world, Friend Owl would be eating Thumper.

This is coevolution: natural selection favors prey that can escape or hide from predators, or even fight them off, but not so much that they cannot grow, and predators that can catch the prey, but not so much that they divert too much energy away from their own metabolism, movement, and growth.

This entry is adapted from my book Life of Earth: Portrait of a Beautiful, Middle-Aged, Stressed-Out World, published earlier this year by Prometheus Books.

Thursday, November 10, 2011

Darwin Had a Sense of Humour

Anyone who has read the Origin of Species would say that it is clearly and beautifully written, with occasional bursts of beauty, even though it is verbose and formal like all Victorian writing. But funny? I wasn’t expecting Darwin’s writing to be funny. But there is a passage in Descent of Man that is funnier than anything I have read by other Victorian writers.

Darwin begins the Descent of Man by presenting evidence of the close similarity of humans and apes. He mentions several anatomical characteristics in which humans and apes hardly differ at all. In this book and in the Expression of Emotions, Darwin notes many behavioral similarities (gestures, facial expressions, etc.) that humans share with apes. But Darwin had very little to say about physiological similarities, because so little was known about physiology at the time. Enzymes? Genes? How nerves work? None of this was known.

Darwin did the next best thing. He presented evidence that humans and other apes have similar physiological reactions to chemicals. One of the chemicals that he chose was alcohol. Here is a really funny passage, in which Darwin explains not only that monkeys can get drunk, but even have similar responses the next day (Chapter 1):

“Many kinds of monkeys have a strong taste for tea, coffee, and spirituous liquors: they will also, as I have myself seen, smoke tobacco with pleasure. Brehm asserts that the natives of north-eastern Africa catch the wild baboons by exposing vessels with strong beer, by which they are made drunk. He has seen some of these animals, which he kept in confinement, in this state; and he gives a laughable account of their behavior and strange grimaces. On the following morning they were very cross and dismal; they held their aching heads with both hands, and wore a most pitiable expression: when beer or wine was offered them, they turned away with disgust, but relished the juice of lemons. An American monkey…after getting drunk on brandy, would never touch it again, and thus was wiser than many men. These trifling facts prove how similar the nerves of taste must be in monkeys and man, and how similarly the whole nervous system is affected.”

A passage that is both funny and scientifically significant. Way to go, Charley!

Friday, November 4, 2011

Darwin Celebrates Halloween

Last Monday was Halloween (or, in the traditional spelling, Hallowe’en, or Hallowed Evening). I taught my evolution class that morning. I wore a T-shirt with a skull on it, with the word “Evolution” over it. Evolution is the name of a little store in the Soho section of New York City which sells items that are vaguely connected with evolution (e.g., tarantulas in plastic).

I then put on a zombie mask and screamed out to the class, “Brains! Brains! BRAINS! BRAINS! I’m Charles Darwin and I’m going to eat your brains and your children’s brains and turn you all into atheists!”

I then removed the mask and explained that Darwin was not a zombie, and that I had no intention of turning anybody into an atheist. I said something like this. “Now, if your religion requires you to believe things that are scientifically disprovable, then I will have to tell you that you are mistaken. But science cannot tell you whether or not there is a purpose behind the universe, or even if there are other universes, or whether this purpose is a personal God. Many scientists believe in God, without any contradiction with their roles as scientists.”

Then I told them about Darwin’s American friend, the Harvard botanist Asa Gray, who was the chief defender of Darwinian evolution in America, but who was as traditional and orthodox a Christian as you could hope to find. A Sunday school teacher, no less. Darwin explained in a letter to Gray how much he regretted that he could not agree with Gray on a religious view. Darwin wrote to Gray, “With respect to the theological view of the question. This is always painful to me. I am bewildered. I had no intention to write atheistically. But I own that I cannot see as plainly as others do, and as I should wish to do, evidence of design and beneficence on all sides of us.”

I then told them about the correspondence I have been maintaining with a prisoner in California. He first wrote to me a couple of years ago when he read my review of an evolution book. He must already have been pursuing an understanding of evolution, because he got my name from a book review I wrote for the National Center for Science Education Reports. He has written to me with many questions, and I have sent answers back to him. I have also sent him paper printouts of things I have written (hardcover books are not allowed in prison mail delivery).

At one point, the prisoner wrote to me about becoming an atheist and the freedom of thought that this allowed him to have. I wrote back to him recently, explaining that atheism was not necessary in order to accept science in general or evolution in particular, and that many scientists are religious. I do not want to lead anyone to atheism. In this way, I am doing exactly what Darwin did. I have not yet received a reply from the prisoner.

I used Halloween as a humorous opportunity to bring up a discussion of this important topic.

Don't miss the YouTube video that I have posted about Darwin and zombies!

Saturday, October 29, 2011

Dinosaur Adventure, part 5. A Race against Time.

Mike O’Brien is a man driven to accomplish as much as possible as well as possible as quickly as possible. For good reason: As I explained previously, the fossil footprints are eroding away. And not just gradually; when the river floods, whole chunks of limestone are broken up into little chunks. There is a drought going on in Texas. The Paluxy River has pools of water but no flowing water. Right now is the time when most of the dinosaur trackways are exposed. Right now is the time to make casts, photograph, and map the footprints. The water has not been this low since 1988. Glen Kuban and I also wanted to accomplish as much as possible, but we cannot resist dropping our work (literally, in Glen’s case; the broom thunks to the ground as he begins talking) to explain the trackways to tourists who walk along the trails or in the riverbed.

But first it was necessary to remove the sediments that had accumulated over the tracks. On the east side of Dinosaur Valley State Park, where Denio Creek enters the Paluxy River, there is a site that needed to be cleaned off before casts, photos, and maps can be made. Mike borrowed a water pump from the park staff, with which he sucked water from a pool into a hose with a nozzle. He used the powerful jet from the nozzle to scour away sediments (see photo). Glen and I pushed brooms around to scoot the water and any remaining rocks and sediments back into the pool. We worked for about two hours, at the end of which time the dinosaur footprints began to just look like holes in rocks. How quickly fascination can turn to fatigue. But Glen and I stopped occasionally to marvel at some of the hundreds of footprints that had been hidden for years. Glen remembered them from 1988, when they were last exposed.

But Mike just kept spraying. He looked like a World War Two hero in a trance with a machine gun. He reminded me of Audie Murphy in the 1955 movie To Hell and Back. He also reminded me of a Gila monster, which is a poisonous lizard that, once he bites (according to legend) he doesn’t let go until sundown. (I mean this in a nice way.) The sun was getting low in the sky.

Unfortunately, I had to leave, but the next morning, Mike and Glen would be back in the riverbed photographing and making casts of the tracks. Their work, for which they are not being paid, is essential: they are preserving a record of some of the most important dinosaur tracks in the world.

Don't miss the YouTube videos of the Paluxy River site!

Also, tonight (October 29) is when Jupiter is in opposition to the Earth, which means it is as close as it will be this year; if you have a telescope, go take a look at it, and see the moons, which are in very different positions every night. This is what Galileo saw that made him question the world-view that almost everyone else had at that time!

Wednesday, October 26, 2011

Dinosaur Adventure part 4. A Creationist Misadventure

I usually post once a week but I want to fit five "dinosaur adventures" into October.

While Glen Kuban, Mike O’Brien, Brian Miles, and I worked on the dinosaur footprints in the bed of the Paluxy River on September 24, we answered many questions from park visitors about the footrpints. Nearly everyone had come with an attitude of fascination about the footprints and a desire to learn about them.

Then along came a creationist couple, apparent followers of Carl Baugh, the weird preacher about whom I wrote previously. They started talking to Glen, since it was clear from the work that he was doing that he was no mere tourist. (What follows is based upon a few observations I made; I was helping Mike most of the time.) This couple made a series of strange statements (even by creationist standards). Glen, who has been clocked at three hundred words per minute, was flooding them with information to demonstrate why they were wrong, both scientifically and theologically. I wanted to tell Glen that no amount of information would change their minds, and he might as well come back and continue working with us. But Glen’s circuit had been closed.

The first strange statement was that the woman said one of the footprints in the riverbed had fit her foot perfectly, and that therefore it had to be a human footprint. This is Carl Baugh’s gospel: humans and dinosaurs lived at the same time and left their footprints in the mud that is now the Paluxy River bed. Glen gave her a few hundred words of rebuttal. What I would have said is, “Listen, lady, human feet come in lots of different sizes. If that footprint fit your foot exactly, then it must have been your footprint. These deposits are 110 million years old. Golly, lady, you don’t look a day over 50 million.”

Then the woman said that the dinosaurs could not have existed before the Fall of Adam, because they would have died before the Fall, and the Bible says there was no death before the Fall, and that Jesus’ sacrifice would have meant nothing at all if any of these dinosaurs had died before Adam. Glen gave her a few hundred words of rebuttal. What I would have said is, “Listen, lady, it’s news to me that Jesus came to Earth to save dinosaurs. Do they have souls? Can you find this in the Bible?”

The woman then said that Glen had been brainwashed throughout his entire life by evolution. Glen explained, in no more than three hundred words, that he used to believe the same thing she did—he had been a creationist who believed that there were human footprints mixed in with the dinosaur prints. He had changed his mind about creationism because he came here in 1980—and has been coming ever since—to actually study the footprints.

The woman then asked if Glen was a Christian. Glen said yes. The woman disagreed with him. (Why did she ask him, then?)

The woman’s husband finally felt he had to intervene. He told Glen something like this (I here take some literary license): “My wife politely explained to you that unless there are human footprints in with the dinosaur footprints in this riverbed, then the entire Bible is wrong, all of Christianity is a lie, and Jesus should never have bothered to come to Earth. My wife here politely told you that she, not you, has the prerogative of determining whether or not you believe in Jesus. My wife POLITELY told you that if you disagree with a single word that she says, that you will burn in hell forever. So why are you talking so fast, which sounds to me like you are upset?” Glen gave him a few hundred words of rebuttal. I would have said, “Well, it appears that when your wife reads the Bible, her brain is incapable of making any errors. She must be personally inerrant. Maybe we should all worship her.” (Besides, just because Glen talks fast does not mean he is upset. Oh, did I say that already?)

Second thought, maybe it’s fortunate that I was not the one talking to the woman.

As I recall, the conversation ended when Mike called Glen over to help. We had a lot of work to do and not many hours of daylight remaining, facts that Mike was continually aware of. We were already dismantling the photographic apparatus so that we could move to another site.

Actually, it turns out Glen was a little upset, not at the couple’s creationist beliefs, but at their arrogance: they assumed that they knew everything about the Bible and about science, without having seriously studied either one. Glen had asked the woman some questions about Biblical passages, which she ignored.

Interestingly, the person who should have been talking to the creationist couple was Brian. He did not go into detail, but I gather that he is a conservative Baptist. His church had hosted Carl Baugh one time, something that Brian considered a big mistake. Brian, as a petroleum geologist, knows perfectly well that the fossils have a millions-of-years evolutionary order. You can use the fossils to determine the relative ages of rock layers and this knowledge can help you find oil and gas. But the woman would probably have told him that he, also, was not a Christian.

It was time for us to go to another track site. Mike hoisted his T-pole onto his shoulder and said, “Well, I will just bear my cross,” as he walked back along the Via Dolorosa of dinosaur tracks toward his van. To be continued.

Friday, October 21, 2011

Dinosaur Adventures part 3. Scientists at Work

Glen Kuban is not the only person who is in a rush to study the dinosaur footprints in the bed of the Paluxy River (Dinosaur Valley State Park, Texas) before they erode away. Glen is hard at work mapping the exact locations of, and making casts of, the footprints. He has done this for a long time, and Glen’s casts and maps from earlier decades are all that remain of some of the footprints. Before making casts, it was necessary for Glen to clean the sediments away and get the water out of the footprints. When I met up with him on the morning of September 24, he was baling water out of holes with a bucket—and each hole was a footprint.

Mike O’Brien, who works for the Texas Parks and Wildlife Department, is also trying to preserve a record of the footprints. He uses a camera mounted on a large T-pole, to produce a gridwork of overhead shots. Mike had made metal grids which we put at precise locations in the riverbed. Later, Mike will electronically stitch these photos together to produce a large image with all of the footprints on it. He hopes to eventually interface his images with Google Earth.

Entirely by chance, we had been joined by Brian Miles, a petroleum geologist who is also the volunteer curator of a small paleontological museum in South Texas, the Brazosport Museum of Natural Science. Brian had heard Glen Kuban and me talking, and he wanted to join us for a few hours. We were glad to have him along. While Mike held his T-pole perfectly perpendicular, Brian would operate the remote control shutter. So on this day there were three of us helping Mike with his overhead photographs (see photograph above). We helped him move the metal grids around also.

Glen, Brian, and I spent a lot of time explaining the footprints to the scores of visitors who were walking in the river bed. Nearly without exception, they were fascinated by the footprints and by what could be learned by studying them. Parents helped their fascinated kids walk right alongside the dinosaur trackways. Some of the teens and tweeners asked some really good questions. And they made some pretty insightful guesses. Some of the guesses were way off, but some were pretty good. And all of these guesses could have been formed into scientific hypotheses. Dare I hope that some of the kids we talked to that day might go on to become scientists, science educators, or at least science hobbyists?

The sun was hot (around 100 degrees) and we got sunburned and thirsty, but we had a good day of work. Glen helped me make videos; Mike got a lot of photos; Glen, Mike, and I explained a lot of things to the visitors. Oh, and by the way, all four of us were doing this for free. To be continued.

Don’t forget to check out my videos about the dinosaur footprints on YouTube. There will be a new one today, starring Glen.

Friday, October 14, 2011

Dinosaur Adventure part 2

As described in the previous blog entry, I went to Dinosaur Valley State Park in Texas, where I met with Glen Kuban, who showed me hundreds of dinosaur footprints in the bed of the Paluxy River. During the ongoing drought, the riverbed was exposed, and with it footprints left by dinosaurs 100 million years ago, when the ground on which we stood had been part of the Gulf of Mexico. In the globally warmed Cretaceous world, sea levels were higher, and reached up into what is now north Texas; also, North America was not quite in the same place that it is now.

Glen helped me make a few video clips, which I am posting, about one a week, on YouTube. In two of them, Glen shows the viewers the dinosaur footprints and explains what you can learn from them. Last week I posted a Darwin video clip; this week, an interview with Glen.

The most interesting revelations about dinosaur life come from not the individual footprints but the trackways of prints. The trackways were left by at least two species of dinosaurs. One was the large, long-necked, herbivorous dinosaur species in the genus Paluxysaurus, which was a sauropod similar to the brontosaurus. What can we learn about these dinosaurs from their trackways? First, Glen pointed out, a group of them was walking in the same direction. They apparently lived in herds rather than as loners. Second, the trackways were close together, indicating that the sauropods walked with their legs underneath them, like birds, rather than out to the side, like lizards. Third, these dinosaurs, though their tails may have weighed a ton, did not drag their tails. This sounds to me like the sauropods had a pretty healthy metabolism and lots of muscle. If they had dragged their tails, they would have left grooves in the mud. See one of the above photos of sauropod trackways. These are the same trackways that I photographed back in March, when they were underwater and visible as green smudges in the photos that I took at that time.

The other species of dinosaur whose prints are common in the Paluxy River bed was a theropod in the genus Acrocanthosaurus; it was sort of a medium-sized T. rex. These dinosaurs left three-toed footprints. The above photos include some adult footprints and a baby footprint (with my foot for scale). The theropods were walking in lots of different directions, and were probably foraging. While it is possible that they were tracking the sauropods to attack and eat them, it is also possible that they were searching for shellfish to eat in the tidal flats. By knowing the size of the dinosaur and the distance between the footprints, it is possible to calculate the speed at which they were walking. Most of them were ambling along, as you might expect if they were looking for seafood left by the receding tide, but in another location the prints were far enough apart that they must have been running at almost 30 miles per hour, which is a very rapid speed for such a large animal—and this was in mud! Imagine how they could have run on solid ground!

The footprints were made 110 million years ago, and subsequently hardened into stone, along with the sediments that had covered them. There may be hundreds of thousands of dinosaur footprints in this layer of rock in northern Texas, but almost all of it is covered with hills. Only in a few places, such as the Paluxy River bed, has this rock layer been exposed by recent erosion. You can’t even find them in the nearby Brazos River, which has apparently eroded through them. Since nobody is going to spend millions of dollars to bulldoze away the hills to expose new footprints, the Paluxy prints represent a rare trove of dinosaur footprints.

And they do not last very long once they are exposed. Large areas of the Paluxy River bed, which used to have dinosaur footprints (even as recently as the 1980s, when Glen began his work), have broken up due to erosion caused by the river. It doesn’t take very long. The river undermines the trackway layer, and then the layer (of soft limestone) cracks and crumbles. Glen and I stood on an approximately 100 square meter slab of limestone with tracks in it, while right beside it was a larger area of riverbed with broken stones which had formerly had dinosaur footprints.

So if you want to see the Paluxy footprints, you’d better go now, while the drought is going on (before God heeds the entreaties of Governor Perry) and before the footprints erode away. To be continued.

Don't forget my website and, if you are interested, my religion blog.

Don't forget my website and religion blog (if you are interested).