Skepticblog

Niles Eldredge as he looks today, Curator Emeritus at the American Museum of Natural History

Experimental biology … may reveal what happens to a hundred rats in the course of ten years under fixed and simple conditions, but not what happened to a billion rats in the course of ten million years under the fluctuating conditions of earth history. Obviously the latter problem is more important.

—George Gaylord Simpson, 1944, Tempo and Mode in Evolution

Last Sunday, Feb. 12, we celebrated the 203rd birthday of two of the most important figures in world history, Abraham Lincoln—and Charles Darwin. To mark the occasion properly, I spent part of my weekend visiting the Creation Museum in Santee, California, with Carrie Poppy and Ross Blocher of the podcast “Oh no, Ross and Carrie!” (more on that trip in my March 7 post). But I thought I’d mark this anniversary with a discussion of another important anniversary in the history of evolutionary science.

(left to right) Stephen Jay Gould, Michael Shermer, and yours truly, Mt. Wilson Observatory, 2001

It was 40 years ago this year that the most frequently cited  paper in the history of paleontology was published. That was none other than the legendary 1972 article by Niles Eldredge and Stephen Jay Gould which proposed the “punctuated equilibrium” hypothesis. (Full disclosure: I took seminars from Niles while I was a student at the American Museum of Natural History, and Steve Gould was very interested in and supportive of my research even though I was not his student in a formal sense). At the time the paper came out, the dominant concept about speciation was the allopatric speciation model. In a nutshell, good biological evidence showed that new species arise not in the large mainland populations (with their extensive gene mixing) but in small isolated populations with unusual gene frequencies (peripheral isolates), usually living separate (allopatric) from the mainland population. Once these allopatric populations were no longer isolated but remixed with the mainland population, they would be genetically and behaviorally distinct from their parent species. Thus, they would be no longer capable of interbreeding, which is part of the definition of a biological species.

Even though the allopatric speciation model was accepted by biologists as early as 1942, it took paleontologists 30 years to recognize its implications. In their historic 1972 paper, Niles and Steve pointed out that if you took Ernst Mayr’s allopatric speciation model seriously, it would predict that species should arise in a normal biological time frame: a few years to a few hundred years at most. That’s a geologic instant, the difference between one bedding plane and the next in strata that span millions of years. The allopatric speciation model also predicted that species should arise in small, peripherally isolated areas, so they were unlikely to be fossilized in the few places for which we have a good fossil record. Rather than slow gradual change through millions of years of strata (the “phyletic gradualism” model), the allopatric speciation model accepted by biologists should give a fossil record where species seem to appear suddenly without any gradual transition preserved (“punctuation”), and then persist for long periods of time without change (“equilibrium”). Continue reading…

JIngmai O'Connor '04 collecting fossils in the Triassic Ichigualasto Formation, Argentina

A teacher affects eternity; he can never tell where his influence stops.

—Henry Adams

In teaching you cannot see the fruits of a day’s work. It is invisible and remains so, maybe for 20 years.

—Jacques Barzun

Having taught at small liberal arts colleges (first Vassar, then Knox College in Illinois, now Occidental College in Los Angeles and also Caltech in Pasadena) for over 30 years now, I’ve experienced all sorts of highs and lows. Sure, there are the bored unmotivated students, the nasty administrators and colleagues, the grind of teaching all my own labs with no help, and teaching the same intro courses year after year, the low pay for long hours with no support for research, the difficulty of getting any time off from teaching to attend essential professional meetings. But there are also the pluses: flexibility of schedule, freedom to teach what I want to teach with minimal interference from above, the small classes where I really get to know the students, and can make sure they understand the material,

But the best benefit of all is the outstanding students who want to do research as undergrads. Since we have no grad program, for years I’ve been treating undergrads as grad students and getting them involved in research. I include them in my field crews or museum research trips (where they find their own projects), help them attend professional meetings and do their own presentations, and help them publish their research. I’ve had many such students over the years, including over 50 different student coauthors on quite a few of my papers. Some, like John Foster ’89, have made it professionally (he’s Curator of Paleontology at the Museum of Western Colorado), and many others are working in environmental or energy firms, earning twice what I make. One never knows how you change the lives of your students when you work closely with them. Of the recent grads, Linda Donohoo-Hurley ’00 finished her Ph.D. at Univ. New Mexico—and I inadvertently introduced her to her future husband, John Hurley, when she presented  our research at a Penrose Conference I organized. Others are about to finish their doctorates. These include Jonathan Hoffman ’03, who came specifically to study with me (M.A. at Florida, nearly done with his Ph.D. at Wyoming);  Josh Ludtke ’04. who took care of my eldest son at times (M.S. at San Diego State, finishing his Ph.D. at Univ. Calgary); and Kristina Raymond ’08, just finishing her master’s at ETSU. Our program is small (only 3-7 graduating geology seniors each year, yet we have 5 full-time tenured faculty), but we turn out a lot of good grad students per capita.

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Even before the annual meeting of the Geological Society of America (GSA)  in Minneapolis started on October 9, there was a huge buzz among my colleagues about this remarkable abstract that claimed evidence of a giant squid, or “Kraken”, that had arranged the bones of the whale-sized ichthyosaurs (marine reptiles shaped like dolphins) from Berlin-Ichthyosaur State Park in Nevada. There was a post on the October 10 page of Pharyngula.org, and also one on Brian Switek’s Laelaps blog, “The Giant Prehistoric Squid that Ate Common Sense”. The only things geologists and paleontologists could evaluate was a short abstract, but it made such a sensational claim that the press was buzzing and the story was all over the internet.

Image of the ichthyosaur bones, showing the "alignment" of the disk-shaped vertebral centra that are alleged evidence of cephalopods arranging the bones.

Based on the abstract and the GSA press release, the argument seemed to be absurd. The only positive evidence presented before the talk occurred was the claim that the bones were arranged in a pattern that resembled the alternating pattern of suckers on the arm of a giant squid. No actual physical evidence of the squid itself—no soft parts, no tentacle hooks, not even the hard “pen” that holds up the back of the animal, or its horny beak. The only “evidence” given in the press release was the alternating pattern of the vertebral centra (the large disk-shaped bones in the photograph). According to the author, this was evidence of a conscious effort on the part of a large cephalopod to “arrange” them that way! There was no mention of the possibility that any string of disks connected in the vertebral column would settle in that pattern once the tissues rotted and fell away from the backbone. No suggestion that the entire premise of the talk was just speculation based on a “pattern” of bone distribution, or “seeing patterns” where there are none, known as pareidolia (such as seeing the Virgin Mary in a grilled cheese sandwich, or reading “patterns” in tea leaves and clouds). PZ Myers of Pharyngula.org immediately got very suspicious, as did Brian Switek, and so everyone was itching to find out if there was more to this story than just a press release. Continue reading…

Spread from Ankylosaur Attack (Kids Can Press, 2011). Art by Daniel Loxton with Jim W.W. Smith. All rights reserved. (Click image to enlarge)

With the release of my new dinosaur storybook, Ankylosaur Attack (available from most booksellers, including Amazon.com, Amazon.ca, and Skeptic.com) many younger scientists (especially those aged four to eight) are asking, “How did you make these pictures look so real?” I’ll be discussing that further at the Vancouver International Writers Festival next week, but I thought I might give Skepticblog readers a first glimpse behind the scenes.

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Two weekends ago, the country was absorbed in remembering the events of September 11, 2001, but September 10 was another anniversary:  the 70th birthday of Stephen Jay Gould, paleontologist, evolutionary biologist, historian of science, Harvard professor, prolific writer and columnist, and probably one of the most influential public scientists of the 20th century. A number of prominent evolutionary biologists and bloggers paid tribute to him, including P.Z. Myers, Jerry Coyne, and others. Even though Steve lived to the age of 60 and passed away on May 20, 2002, most of us were shocked when he was stricken so suddenly by cancer and wasted away to nothing in a matter of weeks. In spite of his rapid decline in health, during his final semester he gamely kept traveling up from his New York apartment to Harvard to teach his classes, even though he was so weak he could barely stand. Though he accomplished more in  his lifetime than any other scientist of his generation (books,  essays, research, scientific papers, etc.), most of us felt that his death at 60 was premature and that he had so much more to offer us had he lived his fullness of years.

Yours truly (right) with Gould (left) and Michael Shermer (center) at Mount Wilson Observatory, 2001.

I should explain to the reader of my personal perspective in this matter. Although I was never formally his student, Stephen Jay Gould was a friend and mentor to me while I was at Columbia University and the American Museum of Natural History (AMNH) as a graduate student from 1976-1982. When I arrived at the Columbia/AMNH program, all the grad students heard the legends of Steve when he was a grad student in the same program two generations earlier. Each year, the stories got more and more amazing: how he outshone all the other students with his brilliance, published his first paper early in grad school, wrote entire papers in a few hours of work, wrote his entire dissertation in a few hours/days/weeks when his advisor Dr. Norman Newell thought he should finish and defend, and so on. His were enormous shoes to fill, and we all felt his shadow when we were being evaluated as students. I saw him on numerous occasions when I was a grad student, not only at professional meetings, but also when he came down to Lamont-Doherty Geological Observatory to see for himself the work that Dave Lazarus and I (Lazarus et al. 1982) were doing on gradual evolution in plankton (he was more open-minded that you would expect), or when fellow student Paul Sereno and I paid a visit to him at Harvard while we were working on a project on allometry and dwarfing in mammals (Prothero and Sereno 1982). Subsequently, he was extremely supportive to me during my professional career, recommending me for a Guggenheim Fellowship (which I got, thanks to  him), plugging my work in his Natural History columns several times, and graciously replying to my letters whenever I had an idea that truly required his attention. When my job and my department at Knox College were about to be eliminated in 1983-1984, he spoke out not only in front of the audience at the GSA meeting, but also wrote letters on our behalf to try to reverse the decision. Thus, I cannot claim to be impartial about Steve, but I do speak from personal experience and from watching paleontology change over the past 40 years.

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What’s in a name? That which we call a rose by any other name would smell as sweet.

—William Shakespeare, Romeo and Juliet

ITEM: A few years ago there was a big fuss in the media about the fact that astronomers had demoted Pluto from one of the classic nine planets to a “minor planet,” just another body in the solar system. Some people were shocked and upset, since they had always learned that Pluto was the ninth planet and didn’t want to unlearn it, no matter what astronomers said. Astronomers pointed out that numerous other small icy objects had been found in the Kuiper belt outside Neptune, including some that were larger than Pluto—but no one was ready to promote 2060 Chiron to the 10th planet. Instead, the logical solution was to demote Pluto to the class of “dwarf planets” along with these other objects, since it really didn’t have much in common with the other eight planets. The state legislatures of Illinois (where Pluto discoverer Clyde Tombaugh was born), New Mexico, and California passed resolutions against the change (despite the fact they had no legal authority in the matter). Caltech astronomer Mike Brown, who spearheaded the change, wrote in his book How I Killed Pluto and Why it Had it Coming that “I’ve been accosted on the street, cornered on airplanes, harangued by e-mail, with everyone wanting to know: why did poor Pluto have to get the boot? What did Pluto ever do to you?” In 2007, the American Dialect Society recognized the neologism “to pluto” (meaning “to demote or degrade”) as the 2006 Word of the Year.

ITEM: In 2010, paleontologists Jack Horner and John Scannella suggested that Triceratops was just the juvenile form of the longer-frilled dinosaur Torosaurus. Once again, there was public outrage and protests. People complained that their beloved three-horned dinosaur was being snatched away from them. Unfortunately, the public and the media got the story completely backward. IF other scientists eventually agree with Horner and Scannella, and formally decide to ratify the idea that Triceratops and Torosaurus were the same animal, then the invalid name would be Torosaurus, not Triceratops. As Brian Switek pointed out in his blog “Relax—Triceratops really did exist”, Triceratops was named by Yale paleontologist O.C. Marsh in 1889; the same scientist named Torosaurus in 1891. According to the rules of the International Code of Zoological Nomenclature (ICZN), Triceratops has priority over Torosaurus, so no one will weep or gnash their teeth if Torosaurus becomes the invalid synonym and is officially demoted. Continue reading…

I am a vertebrate paleontologist. I have collected fossil bones out in the Big Badlands of South Dakota and many other places all over the western United States. Although I have collected plenty of dinosaur fossils, I don’t do research on them, but on fossil mammals that are equally cool, including North American rhinoceroses, horses, camels, musk deer, peccaries, and a number of extinct groups that only another mammalian paleontologist would recognize, such as oreodonts and dromomerycids.

People seem to think that my primary job is to collect new fossils and describe them, but in most cases, this is not true. I could spend dozens of man-years getting sunburned in the desert, and not find but a few really scientifically important specimens. Luckily for me and many other paleontologists, there have been many collectors over the past century who have done the hard work in the field, building up large collections in the major museums. What has been missing for a long time is people who want to spend the months and years figuring out what these new fossils are, describing and publishing them, and giving us a correct and up-to-date picture of what fossil animals lived when and where. This is called systematics, and although it’s not as glamorous as the “Indiana Jones”-”Jurassic Park” image of paleontology that most people think of, it is the most important job in paleontology. Without hundreds of hours of careful work in museums, measuring and studying and photographing and then publishing the fossils in highly specialized  monographs that only a few people can understand, all the computer-driven arm-waving about how many species lived at a given time, or what caused their extinction (all based on outdated names or incorrect identifications) is “garbage in, garbage out.”

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