Many years later, I read an article that featured Wallace Broecker, the Columbia University scientist with revolutionary ideas about catastrophic climate change caused by abrupt slowdowns in ocean circulation. I was fascinated by his idea that the rapid onset of the Younger Dryas cold spell could have been caused by the collapse of an ice dam and a deluge of freshwater into the North Atlantic that shut off the Gulf Stream, stopping the flow of tropical heat to the northern continents and plunging them into ice-age conditions. He showed that there could be other causes of global catastrophes that don't involve impacts.

I was delighted when Broecker agreed to give the opening presentation at the American Geophysical Union (AGU) session I helped organize, but I was surprised to learn that he had abandoned his famous hypothesis about the cause of the Younger Dryas. He started his presentation by reminding everyone that he used to argue that it was triggered by the flood from the ice-age Lake Agassiz, but when he flew over the route the floodwaters should have followed, he saw no geomorphic evidence for a flood. He had changed his mind!

His primary objections to the impact hypothesis were the same as his objections to the flood he had previously championed as the explanation: lack of evidence and lack of uniqueness of the Younger Dryas. Abrupt changes in climate, both warming and cooling, have happened many times, and Broecker argues that the climate system is inherently unstable. Why should only one of a long sequence of changes have such an improbable and catastrophic trigger event—whether impact or flood—when the climate system has repeatedly undergone such changes all by itself?

In his 1987 CSICOP address, Carl Sagan said, "In science it often happens that scientists say, ‘You know that's a really good argument; my position is mistaken,' and then they actually change their minds and you never hear that old view from them again... . I cannot recall the last time something like that has happened in politics or religion."

Broecker's esteem among scientists was not diminished when he changed his mind. The Younger Dryas impact proponents would do well to follow his example.

Mark Boslough was co-organizer of the AGU Younger Dryas session in December. He is a physicist at Sandia National Laboratories and an adjunct professor at the University of New Mexico.

An Evolutionary Algorithm Beats Intelligent Design

How an intelligent design theorist was bested in a public math competition by a genetic algorithm—a computer simulation of evolution.

In the summer of 2006, a different kind of war was waged on the Internet—a war between computer programs written by both evolutionary scientists and by intelligent design (ID) advocates. The war came to a climax in a public math competition in which dozens of humans stepped forward to compete against each other and against genetic ("evolutionary") computer algorithms. The results were stunning: The official representative of the intelligent design community was outperformed by an evolutionary algorithm, thus learning Orgel's Second Law—"Evolution is smarter than you are"—the hard way. In addition, the same IDer's attempt to make a genetic algorithm that achieved a specific target without "specification" of that target was publicly exposed as

a rudimentary sham. And finally, two pillars of ID theory, "irreducible complexity" and "complex specified information" were shown not to be beyond the capabilities of evolution, contrary to official ID dogma.

Genetic Algorithms

"Genetic algorithms" (GAs) are computerized simulations of evolution. They are used to study evolutionary processes and solve difficult (and sometimes intractable) design or analysis problems. Several novel designs generated with genetic algorithms have been patented (Brainz.org 2008). Evolutionary algorithms are currently used in a variety of industries to get effective answers to very difficult problems, including problems whose brute-force solutions would require centuries, even on superfast computers. In contrast, GAs can often produce highly useful results for the same problems in just a few minutes.

The basic idea for a genetic algorithm is simple. You start with a randomly generated "herd" of possible solutions to a given difficult problem, where the general structure of any conceivable solution can be represented with a chunk of memory in a computer program. Treat the members of this herd as "organisms," and test every herd member's performance with a fitness function. While the fitness function can be written in terms of proximity to a distant known "target," it is more often just a straightforward calculation of some parameter of interest, such as the length or cost of some component or feature, or perhaps the gain of a wire antenna. Any candidate organism can have its fitness readily measured, and the performances of any number of candidates can be impartially compared. The fitness test is commonly used to help decide which organisms get to be "parents" for the next generation of organisms. Throwing in some mutations, and letting higher-fitness organisms breed for a few hundred generations, often leads to surprising (and sometimes even astonishing) results.

Creationists and intelligent design proponents vigorously deny the fact that genetic algorithms demonstrate how the evolution of novel and complex "designs" can happen. They claim that GAs cannot generate true novelty and that all such "answers" are surreptitiously introduced into the program via the algorithm's fitness testing functions. The support for this claim stems mainly from a few pages of a book Richard Dawkins wrote nearly twenty-five years ago.

Dawkins and the Weasel

Creationists have been fixated for decades on Richard Dawkins's "Weasel" simulation from his 1986 book The Blind Watchmaker (Dawkins 1986). Unlike real genetic algorithms developed for industry or research, Dawkins's Weasel algorithm included a very precise description of the intended target. However, this precise specification was used only for a tutorial demonstration of the power of cumulative selection rather than for generation of true novelty. In the Dawkins example, the known target is the phrase from Hamlet, "Methinks it is like a weasel." The organisms are initially random strings of twenty-eight characters each. Every generation is tested, and the string that is closest to the target Weasel phrase is selected to seed the subsequent generation. The exact Shakespearean quote is obtained in just a few dozen generations. Despite Dawkins's explicit disclaimer that, in real life, evolution has no long-distance target, creationists of all varieties have latched on to "Weasel" as a convenient straw version of evolution that is easy to poke holes in.

The main ID theorist dealing with genetic algorithms is William Dembski, who stated the ID/creationist position as of September 2005 with these words:

And nevertheless, it remains the case that no genetic algorithm or evolutionary computation has designed a complex, multipart, functionally integrated, irreducibly complex system without stacking the deck by incorporating the very solution that was supposed to be attained from scratch (Dawkins 1986 and Schneider 2000 are among the worst offenders here). (Dembski 2005)

Stephen Meyer is a top gun in the Discovery Institute's Center for Science and Culture, the Seattle-based center of ID pontification and promotion. In Meyer's "peer-reviewed" ID paper, "The Origin of Biological Information and the Higher Taxonomic Categories," he states:

Genetic algorithms ... only succeed by the illicit expedient of providing the computer with a target sequence and then treating relatively greater proximity to future function (i.e., the target sequence), not actual present function, as a selection criterion. (Meyer 2004)

Both Dembski and Meyer cite Weasel in these statements and go on to claim that all GAs are similarly targeted. And that is the gist of the formal ID response to genetic algorithms: paint them all with the Weasel brush, and pretend they all need predefined targets to work.

Steiner's Problem

In 2001, as I was preparing a response to an upcoming talk by ID's Phillip Johnson at the University of New Mexico, I decided to address the Weasel problem. I set out to develop a genetic algorithm of my own for solving difficult math problems, without using any specified target. I wanted something visual yet simple—a sort of miniature digital playground on the very edge of complexity. I ended up choosing "Steiner's Problem": given a two-dimensional set of points, find the most compact network of straight-line segments that connects the points (Courant and Hilbert 1941).

In Steiner's problem, there can be variable "Steiner points" in addition to the fixed points that are to be connected. If there are four fixed points arranged in a rectangle, the Steiner solution consists of five segments connected in a bowtie shape; each of the points on the rectangle's corners connects to one of two Steiner points in the interior of the rectangle, and a fifth segment connects the two Steiner points (figure 1).

A Genetic Algorithm for Steiner's Problem

In my Steiner genetic algorithm, the organisms are represented by strings of letters and numbers—a kind of primitive "DNA." Two such DNA strands are shown in figure 2. The strands, when read by the transcription routine, supply three types of information about the network represented by each organism: the number of Steiner points, the numerical locations of these points, and a true/false connection map that dictates which points are to be connected by segments.

Steiner points can be placed anywhere in the region encompassing the fixed points; for these simulations, the region is a square with 999 units on a side. Length is measured in these units; for example, the length of the horizontal segment joining points (550,600) and (650,600) is 100 units.

Some representative networks for a six-point Steiner problem appear in figure 3. These are the "phenotypes" that correspond to the transcription of DNA (or the "genotype"). The fitness function used tests for two things: Are the fixed points all connected? What is the total length of all "expressed" segments? It's critical to emphasize that the fitness function need not have any descriptions of the actual Steiner solution for any given set of points. Fitness, here, is not based on any specific future function but only on present function. For example, the two organisms of figure 3 are clearly not the optimum Steiner solution for six fixed points (solid circles) in a rectangle. Yet, they can both easily be evaluated for current function. Here, the organism on the right is considerably shorter than the one on the left, and thus it has a better chance of having its "seed" continue on to the next generation. If an organism fails to connect all the given points, it is given a large "death" length of 100,000 units, making it extremely "unfit."

The Cyber Battles Begin

I posted a detailed discussion of this work on the Panda's Thumb blog on July 5, 2006. The point of that report was to demonstrate that genetic algorithms can solve difficult problems without knowing anything about the answer(s) in advance. I demonstrated that, while occasionally producing the correct (Steiner) solution, most of the time the algorithm converged on imperfect solutions. I called these "MacGyver" solutions, after the television hero who often found clever ways to get out of tough fixes. While the MacGyver solutions are clearly not the optimum Steiner shape, they get the job done efficiently and are often within one percent of the length of the formal Steiner solution itself. The GA operates by seeding the next generation with those organisms that are shorter in length in the current generation. This GA does not, as Meyer falsely claims, select for future function (a precise target) rather than for present function (here, the lengths of the digital creatures).

The ID community responded to my article by simply reiterating their claim that the solutions were secretly introduced via the fitness function. IDers are desperate to make Dawkins's Weasel the poster boy for all GAs, and they continue to paint all GAs as similarly "target-driven" or "front-loaded." Some ID theorists have tried to skirt the obvious lack of specific target description in the Steiner genetic algorithm by claiming that its virtual environment—the condition "shorter is better"—is really a description of the "precise target" itself. They say, "After all, you wanted shorter networks, and the Steiner solution is defined as the shortest network, so you are selecting for a specific target!"

This ID argument fails because the specific details of complex solutions are not explicitly imbedded in the overall design goals. To use an analogy, simply stating the objective "Build a vehicle that can carry men to the Moon and back" does not result in the spontaneous appearance of the complete plans for an Apollo spacecraft (with separate command, service, and lunar modules), along with a Saturn V launch vehicle.

The Collapse of the Pillars of ID Theory

One reason I chose Steiner's problem was that Steiner solutions possess "irreducible complexity" (IC) and also exhibit "complex specified information" (CSI), two features that intelligent design theorists claim are impossible via evolutionary processes. I contend that the results of the GA—both Steiners and MacGyvers—exhibit IC: if any segment is removed or rerouted, basic function of the system (here, connecting the fixed points) is lost completely. In addition, the Steiner solutions themselves are CSI, by virtue of their being complex (in the sense that the correct answer is rare enough to be improbable) and by virtue of their nature as specified information (as the formal solution to a given math problem).

ID proponents responded by claiming that the Steiner solutions discussed were "not really IC," even though these solutions obviously represent "a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning," the very definition of IC from Michael Behe's book Darwin's Black Box (Behe 1996). Behe goes on to claim that IC structures are impossible in gradual evolution (improvement by slight, successive modifications to precursor systems) "because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional."

The general ID response to my article was that the Steiner solutions could not be IC because they were derived from ancestors that were longer but still functional. So, the very existence of functional precursors is now being used to redefine irreducible complexity. IC apparently no longer has anything to do with the existence of critical, precisely interlocking components. This is classic goal-post movement. The concept of IC has become a useless tautology: if it's IC, it can't have evolved, and if it evolved, it can't be IC. Of course, Behe was thinking only about bottom-up evolution initially. In the Steiner GA, however, populations of organisms often become less complex through shedding of redundant complexity. This type of pathway to IC structures has been observed numerous times in nature.

The ID Version of a Genetic Algorithm

Bill Dembski's coauthor of his Uncommon Descent blog, software engineer Salvador Cordova, was the most prominent member of the ID community to weigh in on the series of GA articles. Cordova repeatedly misrepresented GAs as necessarily "front-loaded" and dismissed the results as "computational theatrics." On August 15, 2006, Cordova posted his code for a genetic algorithm, which he contended could solve for the sum of the first 1,000 integers without specifying the answer. He said this program was based on the same "theatrics" I was employing in my Steiner GA. However, I proved that his program was, despite copious amounts of smoke and mirrors, simply a direct method of specifying the answer, or target. Instead of matching the string "Methinks it is like a weasel," Cordova engineered his GA to converge on the specific target sequence 251, 252, 253, ... 750. Cordova then added these 500 numbers and doubled that sum, inevitably arriving at the sum of the integers from 1 to 1,000, or 500,500. It was easy to prove that his badly written and confusing program was a direct encoding of a fixed target, leading directly to the summation of the first N integers.

The Design Challenge

On August 14, 2006, I posted a public "Design Challenge" on the Panda's Thumb blog in which readers were given one week to submit answers for the tricky six-point Steiner system shown in figure 4. It was an open-book test. Since the ID person responding to this discussion, Salvador Cordova, had been claiming that the answer was "front-loaded" into the fitness test, I challenged him to follow that lead to the answer.

I had come up with the six-point problem two days earlier, while trying to design a system that would have the "double bowtie" as its Steiner solution (figure 5). Upon reviewing an overnight batch of three-hundred runs, however, I was surprised to see solutions with lengths much shorter than the double bowtie's 1,839 units. And when I checked out the GA's best solution, the odd design shown in figure 6, it was like finding a diamond in the rough. I realized the GA had found the correct Steiner solution, and it wasn't what I had been expecting at all. Instead of the double bowtie, the actual Steiner solution twists both bowties a bit, and they become conjoined in a three-segment "dogleg" along the center vertical. There are two possible Steiners, one with the bowties skewed up and the other with them skewed down. The GA found both solutions, along with hundreds of compact MacGyvers.

Dozens of Panda's Thumb readers responded to the Design Challenge. Most were pro-science enthusiasts, but ID theorist Cordova submitted several candidate answers as well. Cordova had repeatedly compared the Steiner GA's fitness function to a T-shirt with a large bull's-eye emblazoned on it and the Steiner solution itself to the person inside that shirt. He analogized shooting a paintball gun at the bull's-eye symbol and then telling the victim, "Don't be mad, I wasn't aiming at you, I was aiming at the shirt you were wearing." Curiously, Cordova did not reverse-engineer my publicly posted GA (the shirt) to deduce the solution (e.g., the person wearing the shirt). Instead, he went the traditional route and tried to design an answer using Fermat points and trigonometry. Interestingly, Cordova failed to deduce the basic network shape for the six-point solution, finding instead the slightly longer MacGyver solution of figure 7. Fifteen other "intelligent designers" (humans, in other words) were able to derive the correct answer—the true Steiner solution. However, all of these humans were pro-science skeptics of intelligent design creationism. Correct solutions were also found by not one but two independent genetic algorithms! An additional fifteen designers derived various MacGyver solutions, thus proving these, too, are complex specified information.

And that's how ID theorist Cordova learned the true meaning of what Daniel Dennett terms Leslie Orgel's Second Law: "Evolution is smarter than you are."

After being bested by an evolutionary algorithm, Cordova changed his tune and moved the goalposts over to computer speed. He said there was no shame in being beaten by the computer because computers are designed to do lots of math very, very fast and are thus superior to humans in that regard. But that argument doesn't wash either. The computer can check out lots of random solutions very quickly (about 8,000 per second), but simply guessing randomly at the answer is a terrible way to solve the problem. After dozens of hours, random guessing couldn't come close to matching even one of the efficient designs the genetic algorithm was pumping out every ninety seconds (figure 8).

Conclusion

The 2006 "War of the Weasels" was, to say the least, not kind to the ID movement. The central dogma of ID regarding genetic algorithms—the Weasel offense—was definitively and publicly shot down. ID theory's two main "evolution stoppers"—irreducible complexity and complex specified information—were shown to be child's play for an evolution-based program that evaluates current function only and is mindless of any specific future optimum. Finally, an ID "theorist" was bested by a program that used evolution to derive solutions. Check out the complete archives of the War of the Weasels on the Panda's Thumb blog, in the "Evo Math" category. l

References

Behe, Michael. 1996. Darwin's Black Box. New York: The Free Press.

Brainz.org. 2008. 15 real-world uses of genetic algorithms. Available online at http://brainz.org/15-real-world-applications-genetic-algorithms/.

Courant, Richard, and Herbert Robbins. 1941. What is Mathematics? London: Oxford University Press.

Dawkins, Richard. 1986. The Blind Watchmaker. New York: W.W. Norton and Company.

Dembski, William. 2005. Rebuttal to reports by opposing expert witnesses. Design Inference, May 14. Available online at www.designinference.com/ documents/2005.09.Expert_Rebuttal_Dembski.pdf.

Meyer, Stephen. 2004. The origin of biological information and the higher taxonomic categories. Proceedings of the Biological Society of Washington 117(2): 213–239.

The rise and fall of the theory that cosmic catastrophes altered human prehistory in North America.

Ever since the Alvarez (1980) hypothesis that the end-Cretaceous (Cretaceous-Tertiary or KT) mass extinction was the result of a cosmic impact sixty-five million years ago, the idea of killer asteroids or comets has been frequently discussed. The stunning confirmation of the KT impact initiated a revolution in our thinking about possible external events and their effects on biological evolution. David Raup of the University of Chicago famously proposed that perhaps all major mass extinctions were impact induced. He even published a "kill curve," suggesting that lesser extinctions might be the result of smaller impacts. Unfortunately for those of us who sought a general explanation for mass extinctions, these broader suggestions have not been verified. It seems increasingly likely that cosmic impacts are only one of several catastrophic events that have produced mass extinctions. Still, the discovery that an impact sixty-five million years ago led to the extinction of the dinosaurs remains one of the iconic ideas of late twentieth century science.

The most dramatic recent hypothesis linking extinctions with impacts was proposed in 2007 by a team of twenty-six scientists, led by nuclear chemist Richard Firestone of Lawrence Berkeley National Laboratory, with independent geophysicist Allen West; geologist James Kennett of the University of California, Santa Barbara (a member of the National Academy of Sciences); and archaeologists Douglas Kennett and Jon Erlandson of the University of Oregon. In a widely reported presentation at a joint assembly of the American Geophysical Union (AGU) in Acapulco, Mexico—followed a few months later by a paper in the Proceedings of the National Academy of Sciences (PNAS)—these scientists proposed a cosmic origin for a geologically recent event, the extinction of many large mammals (megafauna) in North America approximately 13,000 years ago. The events they linked were the presence of a dark soil layer that coincided with the extinction of megafauna (including the mammoth and mastodon), the end of the Clovis culture (identified by its large and well-made spear points), and the start of the Younger Dryas (YD) cool period (a millennium pause in the general warming at the end of the last ice age). The in situ bones of extinct megafauna, along with Clovis stone tools, occur below this black mat but not within or above it. At this boundary the team reported finding enriched levels of iridium and other signatures of extraterrestrial material.

In a sweeping conclusion reminiscent of the Alvarez hypothesis, Firestone and his colleagues postulated that these events were tied to one or more cosmic impacts over North America, releasing energy they estimated at about ten million megatons (equivalent to an impacting comet four kilometers in diameter). They suggested that an airburst and/or surface impact by a dense swarm of carbonaceous asteroids or comets set vast areas of the North American continent on fire. This swarm would have exploded above or even into the Laurentide Ice Sheet north of the Great Lakes. Such an airburst would have been a million times larger than the Tunguska impact event of 1908.

Scientific Reactions

While archaeologists pondered the reality of this sharp boundary layer and the new evidence of extraterrestrial materials, a few astronomers and impact experts immediately questioned this scenario. They noted that there was no mechanism to hold such a dense swarm of impactors together in space. To the suggestion that a large comet had broken up just before hitting Earth, they replied that this lacked a physical mechanism. If the comet had shattered when it encountered the atmosphere at an altitude of about one hundred kilometers, the lateral dispersion would be at most tens of kilometers, hardly enough to distribute the effects across North America. An alternate suggestion was that this event was analogous to the 1992 tidal break-up of comet Shoemaker-Levy 9, which resulted in the separate impact of about twenty-three fragments on Jupiter two years later. However, these comet fragments were spread over more than a million kilometers in space, and the impacts were distributed over all longitudes on Jupiter. While it is true that some comets have been seen to spontaneously disintegrate in space, the chances of this happening just before an impact with Earth is negligible—something that might have happened at most once in the past four billion years. There was apparently no way to get a swarm of impactors to target North America alone.

One of Firestone and his colleagues' suggestions that troubled geologists and impact experts was that the same event (or a similar one) might have been responsible for the Carolina Bays geologic formation. The Carolina Bays are several hundred thousand shallow, elliptical depressions of disputed origin along the U.S. eastern seaboard. Firestone suggested that each of these more than 100,000 features was the result of a cosmic impact. Since the well-known Tunguska airburst in Siberia in 1908 did not form a crater, the implication is that these were made by larger objects that reached the ground. But calculation of average impact frequency suggested that only about one super-Tunguska could be expected to hit Earth in the past 13,000 years. The chances of two such extremely unlikely swarm impacts happening within the past few thousand years is worse than negligible.

A warning of the problems with this hypothesis should have been apparent to anyone who read 2006's The Cycle of Cosmic Catastrophes: Flood, Fire, and Famine in the History of Civilization by Richard Firestone and Allen West, with writer and publicist Simon Warwick-Smith. This trade book, which appeared a year before Firestone's AGU presentation, described the YD impact hypothesis as part of a much larger cycle of cosmic events. This book develops Firestone's 2001 suggestion that a cosmic ray catastrophe, probably caused by a supernova, occurred in northeastern North America in the late Pleistocene. He concluded that massive thermal neutron irradiation radically altered the radioactivity of terrestrial materials and "probably figured in the mass extinction of Ice Age fauna." In The Cycle of Cosmic Catastrophes, Firestone links the YD impact to this postulated nearby supernova, which he asserted took place 41,000 years ago and initially devastated most life in Asia. Then 34,000 years ago the shock wave from this supernova initiated another wave of intense cosmic bombardment of Earth. The only evidence for this event is the remarkable claim that mastodon tusks from about that time are pitted with cosmic dust, suggesting that these animals received the direct blast of supernova material striking Earth (unstopped, apparently, by our atmosphere).

In The Cycle of Cosmic Catastrophes, the debris cloud from the supernova is supposed to have reached Earth about 13,000 years ago. The YD impact was one manifestation of this blast wave, bathing the planet in radioactivity and destabilizing the magnetic field. In this book the authors suggest that the Carolina Bays were created by secondary impacts of ejecta from the main hit in the North American ice sheet. To produce this much ejecta, the hit must have been among the most catastrophic events in Earth's history. They suggested that the YD impact excavated Hudson Bay, making it larger than the KT impact of sixty-five million years ago, which is estimated to be a once-in-one-hundred-million-years event. Yet supposedly this huge hit did not produce a worldwide mass extinction but influenced only the megafauna of North America. This entire scenario is inconsistent with what astronomers know about supernovas, which Phil Plait summarized in his recent book Death from the Skies. It raises serious questions about the reliability of the PNAS paper that Firestone and West, with two dozen additional authors, published a year later.

New Data and Continued Controversy

In January 2009, Doug Kennett published a paper in Science asserting that nanodiamonds provide the strongest evidence for the impact hypothesis, with multiple airbursts and impacts at the onset of the YD cooling. He argued that these nanodiamonds were produced in the moderate shocks associated with comet airbursts. By this time, earlier claims about iridium enrichment and other possible impact markers had been withdrawn. The usual geological evidence of large crater-forming impacts such as the KT, namely shocked quartz, had never been reported at the YD boundary sites. Now the nature and origin of nanodiamonds became the primary issue.

There were a variety of claims and counterclaims concerning the nanodiamonds. Were they produced in the impact, or were they primordial material trapped in the comet when it formed billions of years earlier? Most impact experts agree that nanodiamonds were unlikely to have been formed in the impact. In fact, Mark Boslough of Sandia National Laboratories calculated that the high temperatures and pressures in a large impact would likely destroy existing nanodiamonds. Some note that nanodiamonds are actually ubiquitous on Earth and can even be formed in fires. One scientist joked that perhaps the nanodiamonds were concentrated at human habitation sites where hunters were roasting the meat from mammoths and mastodons. The history of these claims and counterclaims is well documented in articles by Science journalist Richard Kerr published in 2007, 2008, and 2009.

At a meeting of the Geological Society of America (GSA) in October 2009, several presentations argued strongly against the YD impact from a variety of perspectives (see GSA summary in references). One paper claimed that the black mats at the YD boundary were not charcoal from widespread fires but rather peat-rich dark soils formed during a wet period. Another speaker noted that there was no archeological evidence for a sudden decline in the human population of North America at the YD. While one speaks of the end of the Clovis culture, this only means that the style of stone tools changed. We don't know why, although one possibility is a shift to hunting smaller animals. Other scientific teams reported that their efforts in the field to find nanodiamonds or other impact markers at the YD boundary layer were unsuccessful.

Some impact proponents who were not present at the GSA meeting wrote blogs and circulated e-mails accusing these scientists of sloppy fieldwork. They asserted that the boundary layer was very thin and rather spotty in distribution, requiring care to find it—care they implied had not been exercised by their critics. The GSA session resulted in the undercutting of the credibility of the original PNAS and Science papers, but since the two sides did not confront each other directly, nothing was settled.

The American Geophysical Union Symposium

Given the conflicting interpretations concerning a possible YD impact catastrophe, many scientists thought a debate between proponents and critics might help clear the air. The YD impact hypothesis had been discussed for more than two years without any common ground emerging. Indeed, the original team of twenty-six scientists was itself fragmenting, with only Richard Firestone and Allen West still strongly advocating the original multi-comet impact scenario. Mark Boslough of Sandia worked with Allen West to organize a symposium at the 2009 fall meeting of the AGU, with speakers from both sides. While no one expected that public discussion would lead to reconciliation, the organizers hoped this symposium would at least focus on the main issues.

The December 2009 AGU session topic was "Younger Dryas Boundary: Extraterrestrial Impact or Not?" Ten speakers were squeezed into a single two-hour session, including Allen West, impact specialist Peter Schultz of Brown University, and former NASA geoscientist Ted Bunch from among the original PNAS authors. Firestone chose not to attend. There was standing room only at the session, and several hundred others were turned away at the door.

The star of the event was Wally Broecker of the Department of Earth and Environmental Sciences at Columbia University. Broecker is one of the most respected environmental scientists in the world. Credited with first describing the ocean current conveyer belt and inventing the term "global warming," his honors include membership in the National Academy of Sciences and award of the Presidential Medal of Science. His presentation was sober and low key, but he made it clear that he was unconvinced by the evidence for an impact or any catastrophic change at the YD boundary. But rather than condemning the hypothesis, he stated simply that the decline in the North American megafauna could be understood as a result of climate change and overhunting—the conventional explanation. Broecker said, "We do not need the impact hypothesis."

Most of the speakers who followed Broecker restated positions that were already on the record. West and his colleagues repeated their evidence of extraterrestrial markers in the black mat at the YD boundary, with emphasis on the presence of nanodiamonds. They suggested several possible impact scenarios, such as oblique impact on the ice sheet, but admitted that there were many uncertainties. Several critics reiterated that the proposed impact is highly unlikely statistically and that an airburst as large as proposed is inconsistent with our understanding of comets and the impact process.

The most interesting new results were presented by Jacquelyn Gill, a graduate student in the Department of Geography at the University of Wisconsin–Madison. She has been studying lake sediments that contain spores of sporomiella (a fungus that occurs in herbivore dung) in the time range around the YD. This fungus is related to the total mass of herbivores and can be used as a proxy for the megafauna population. Her data show a gradual decline, beginning well before the YD marker and extending beyond the end of the Younger Dryas cool period. Indeed, in some isolated locations mammoths and mastodons did not go extinct until much later: there were dwarf wooly mammoths on Wrangle Island in Alaska until about four thousand years ago. Some large North American mammals did not go extinct at all, including the bison, the moose, and the grizzly bear. Gill's results seem consistent with the worldwide evidence that rapid declines in large mammal population accompanied the arrival of early human hunters, presumably as a consequence of overhunting.

Unfortunately, the overcrowded session ran late, and there was no time for discussion or questions. Even when their conclusions were challenged, most of the scientists in the audience chose not to respond. The result was a lost opportunity for real debate. Perhaps not surprisingly, the AGU session received very little press attention. Indeed, following the AGU and GSA meetings, the YD impact hypothesis seems to have retreated into the obscurity of a few e-mail list-serves and blogs, such as "The Cosmic Tusk" where George Howard (one of the original PNAS authors) is presiding over a variety of catastrophist interpretations of Holocene history.

Conclusions

It is instructive to compare the trajectories of the YD and KT impact hypotheses, as there are close parallels. Both research teams were led by nuclear scientists (Luis Alvarez and Richard Firestone) from the University of California, Berkeley. Both challenged the orthodoxy of mass extinctions. Both postulated an environmental catastrophe triggered by a large cosmic impact. Both were published initially in prestigious journals (Science and PNAS). They each presented a grand synthesis, not only identifying evidence of extraterrestrial materials at the extinction boundary but also proposing a broad impact scenario to explain a wide variety of previously unrelated data. And both ideas were initially resisted by the "old guard" of paleontologists and archaeologists.

While each hypothesis encountered initial resistance, the KT impact theory also gained enthusiastic support (see popular accounts by Walter Alvarez and James Powell). The first confirming paper was published within weeks, and soon multiple impact markers had been identified at a number of additional exposures of the KT boundary. Astronomers and geologists praised the paper and provided context by estimating the impact rate for ten-kilometer comets and asteroids. Atmospheric scientists such as Brian Toon and Kevin Zahnle of NASA Ames Research Center calculated the dispersion and lifetime of dust ejected into the stratosphere by the impact. Paleontologists like Peter Ward (University of Washington)—who initially argued for a gradual decline of populations—gathered new field data and used modern statistics to support an abrupt extinction at the KT boundary. Within three years the first of a series of Snowbird Conferences was held, bringing together top scientists to discuss the role of cosmic impacts on the evolution of life. The idea of an impact extinction gained early and continuing currency in the press.

In contrast, efforts by other scientists to confirm the presence of impact markers at the YD boundary have so far been unsuccessful. Astronomers, rather then welcoming the impact idea, have raised serious objections to the proposal by Firestone and colleagues. New data on megafauna extinction, such as the work of Gill, point to a gradual decline. Archaeologists emphasize that changing styles in stone tools do not demonstrate a sudden shift in human populations at the start of the YD but merely a change in technology or hunting style. In the aftermath of the 2009 GSA and AGU meetings, the press seems to have lost interest, and continuing support for the YD impact comes mostly from blogs by catastrophists who have long advocated cosmic intervention in human history.

Even without considering the technical issues at stake, there are two clues that something is amiss with the YD impact hypothesis. First is the 2006 book The Cycle of Cosmic Catastrophes, which formulates the YD hypothesis within the context of catastrophist pseudoscience. If more scientists and science journalists had been aware of this earlier publication when the YD hypothesis was first published in PNAS, it might never have gained traction. Second is the absence of confirming or supporting papers by scientists who were not members of the original team. A good hypothesis naturally accretes confirmation and gets better with time, as did the Alvarez KT impact hypothesis. Firestone's work has not done so.

It seems clear that the YD impact proponents were trying to follow in the footsteps of the Alvarez team, discovering evidence of a sudden extinction event and linking this to an extraterrestrial impact. However, the story isn't working out that way, and the impact they propose seems to be virtually impossible. One parallel that troubles me, however, is that the reaction of the traditionalists—scientists who say that the megafauna were in decline anyway and "we don't need an impact"—rather closely echoes the reaction of many old-guard scientists to the KT impact hypothesis. There also may be philosophical and political overtones that influence the reception given any proposal that deals with early human history. There is a long tradition of catastrophist ideas, going back to the biblical flood and Plato's story of Atlantis. Philosophically, many people prefer the idea that humans have not had much effect on the planet, either 13,000 years ago or today—better to blame thunderbolts from the gods than to accept responsibility for our stewardship of Earth.

Acknowledgments

I am grateful to Mark Boslough, Clark Chapman, and Alan Harris for many stimulating discussions of the YD impact hypothesis and especially for their insightful and generous suggestions for improving this paper.

References

Alvarez, L.W., W. Alvarez, F. Asaro, and H.V. Michel. 1980. Extraterrestrial cause for the Cretaceous-Tertiary extinction. Science 208: 1095.

Alvarez, W. 1997. T. Rex and the Crater of Doom. Princeton University Press.

Firestone, R.B., and W. Topping. 2001. Terrestrial evidence of a nuclear catastrophe in paleoindian times. Mammoth Trumpet Magazine (March): 9, published by the Center for the Study of the First Americans.

Firestone, R., A. West, and S. Warwick-Smith. 2006. The Cycle of Cosmic Catastrophes: Flood, Fire, and Famine in the History of Civilization. Bear and Company, Rochester, Vermont.

Firestone, R.B., et al. 2007. Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling. Proceedings of the National Academy of Sciences 104: 1616.

Geological Society of America (GSA) Annual Meeting (October 18–21, 2009), Portland, Oregon. Relevant oral presentations, with quotes from their abstracts. Paquay et al.: No evidence of extraterrestrial geochemical components at the Bølling-Allerød/Younger Dryas transition. ("Our study discredits the YD impact hypothesis.") Surovelle and Holliday: Non-reproducibility of Younger Dryas extraterrestrial impact results. ("We were unable to reproduce any results of the original Firestone et al. study and find no support for Younger Dryas extraterrestrial impact.") Pinter et al.: Extraterrestrial and terrestrial signatures at the onset of the Younger Dryas. ("Many of the purportedly unique markers at the YD boundary layer were found in most or all other sites and horizons analyzed, often at concentrations much higher than at the YD layer itself.") Holliday and Meltzer: Geoarchaeology of the 12.9 ka impact hypothesis. ("Sites purported to provide direct evidence of the 12.9 ka impact are not well constrained to that time. An ET impact is an unnecessary ‘solution' for an archaeological problem that does not exist.")

Gill, J., J.W. Williams, S.T. Jackson, K.B. Lininger, and G.S. Robinson. 2009. Pleistocene megafaunal collapse, novel plant communities, and enlarged fire regimes in North America. Science 326: 1100.

Kennett, D.J., et al. 2009. Nanodiamonds in the Younger Dryas sediment layer. Science 323: 94.

Kerr, R. 2007. Mammoth-killer impact gets mixed reception from Earth scientists. Science 316: 1264.

———. 2008. Experts find no evidence for a mammoth-killer impact. Science 319: 1331.

———. 2009. Did the mammoth slayer leave a diamond calling card? Science 323: 326.

Powell, J. 1998. Night Comes to the Cretaceous: Dinosaur Extinction and the Transformation of Modern Geology. Freeman.

Plait, P. 2008. Death from the Skies: These Are the Ways the World Will End. Viking Press.

Raup, D.M. 1991. Extinction: Bad Genes or Bad Luck? W.W. Norton.

Signor, P.W., and J.H. Lipps. 1982. Sampling bias, gradual extinction patterns, and catastrophes in the fossil record. In: Geological Implications of Impacts of Large Asteroids and Comets on the Earth, L.T. Silver and P.H. Schultz, editors. Geological Society of America Special Publication 190: 291.

Toon, O.B., K. Zahnle, D. Morrison, R. Turco, and C. Covey. 1997. Environmental perturbations caused by the impacts of asteroids and comets. Reviews of Geophysics 35: 41.

Ward, P.D., W.J. Kennedy, K.G. MacLeod, and J.F. Mount. 1991. Ammonite and inoceramid bivalve extinction patterns in Cretaceous/Tertiary boundary sections of the Biscay region (southwestern France, northern Spain). Geology 19: 1181.

Debora Moscogiuri was a mystical seer living in Manduria (Taranto) in southern Italy. During ecstatic periods, she could supposedly see and receive messages from the Madonna, which she would then deliver to worshippers. Other phenomena were said to take place in and around the seer's home, including religious icons (pictures and statues) allegedly weeping blood. As is usually the case, none of these phenomena had been carefully investigated or documented, nor were DNA tests performed to ascertain the origin of the blood.

In 1995 one of Moscogiuri's statues of the Virgin Mary allegedly began to drip olive oil. Sealed containers, such as small bottles or jars, left in the proximity of the statue were later found to be partially filled with oil. These had been tied with ribbons, taped, sealed with wax, and placed inside plastic bags. At Moscogiuri's request, some olive leaves were placed inside the bottles before they were sealed.

This phenomenon was reproduced when Dr. Giorgio Gagliardi, a physician from Milan, prepared two such wax-sealed containers: one was kept in his office and a second identical one was sent to Manduria, which was returned to him weeks later with some oil in it—still sealed. Nothing had happened inside the jar kept in Milan. Realizing that wax and tape seals are inadequate against tampering, Gagliardi asked us about secure, "tamper-evident" containers.

Evidence of Tampering

When testing psychic claimants, it is sometimes necessary to allow the subject to take some target material away from the laboratory in order to try and obtain a psychic effect on it in his home. Until a short time ago, the importance of using foolproof containers when conducting this kind of experiment was not fully recognized. Consider, for example, the naiveté with which some parapsychologists investigated the claimed psychokinetic powers of children and teenagers in the past. Since children and teenagers were thought unlikely (or unable) to cheat, they were too readily left alone with target material, such as spoons or pieces of metal to bend. Then, when bends were found in the material, psychic investigators immediately assumed that some kind of psychic force was at work. Later investigations showed these suppositions to be wrong, and now stricter controls are (or should be) used when testing psychic claims.

Preparing "fool-proof" containers (e.g., bags, envelopes, or boxes), which do not allow the subject access to the item contained inside, has always been a challenge. However, preventing access to the item (e.g., by placing it in a steel safe) is probably not as important as making sure that the container is "tamper-evident," meaning it is prepared in such a way that any improper attempt to open it can be easily detected. Special security items are now used to this end. The old sealing wax, for example, has been replaced by self-adhesive labels that show signs of physical tampering, such as attempts to peel it off or the application of heat or solvents. These strips also carry unique identification numbers, used to determine when someone has replaced a strip with a duplicate after opening the container.

Sealing the Tubes

Returning to our investigation of Debora Moscogiuri, Luigi and I confirmed with Gagliardi that the kind of seals he had used could be easily opened and later replaced. Therefore, we prepared a set of sealed test tubes as follows: a) an olive leaf was put into each glass test tube; b) the tubes were flame-sealed on a Bunsen burner, taking care not to scorch the leaf inside; c) each tube was numbered in several positions using a vibrating glass-etching instrument; d) each tube was checked for invisible gaps by holding it under water (in such conditions small air bubbles would escape from those imperfectly sealed); e) the tubes were weighed on a precision lab balance (tared just prior to this operation), recording all digits within a milligram of precision; f) each tube was then photographed with additional close-up lenses to record the etched number and shape of the sealed tip, where the glass had been melted.

When these tubes were slightly heated, the leaf inside gave off a few tiny droplets of water. The general look was quite different from that of oil, the total weight of course did not change, and the droplets were re-absorbed after a few days. Thus we decided not to worry about this detail. Each tube could then be identified by its weight and photograph, and each was "tamper-evident," as there is no way that glass can be melted and resealed exactly in its original shape.

Eight of these vials (numbered 1, 2, 3, 4, 6, 7, 8, 10) were delivered to Moscogiuri through Gagliardi and Father Civerra, a Catholic priest who followed the seer. We did not know the whereabouts of the sealed tubes, nor what was happening to them at the other end of Italy.

Surprise, Surprise!

Two notable events followed. We received news from Civerra, wherein he reported a mystical vision by Moscogiuri of the Blessed Virgin: she had seen a large tongue of flame (of the Holy Ghost) approach the tubes and take one of them away, leaving just seven (the number of the Virgin's sorrows). Later, there was speculation that some of our tubes contained oil.

Through the intermediacy of Gagliardi and Civerra, we managed to get our tubes back. We then examined them during a videotaped meeting attended by both Gagliardi and Civerra. Afterward, all participants signed a statement of the results. Civerra had put the tubes we had prepared into a jar and then into a plastic bag; each of these containers had been wax-sealed. For the reasons given above, we disregarded these extra security measures and requested that only our tubes be taken out and checked. It should be noted that when asked, Civerra admitted that he had no way of verifying whether his wax seals had been tampered with and replaced.

It turned out that: a) one of the eight tubes (number 3) was missing; b) tubes 1, 2, and 7 were intact and did not contain any liquid; c) tube 4 had a broken tip that had produced a small gap, but no liquid was present; and d) tubes 6, 8, and 10 contained a yellow viscous liquid.

A comparison with the photographs of the originals showed that the tips had been melted and resealed. The shapes of the tips were clearly different. One of the tubes had been tampered with on the side, and the glass was deformed, leaving a large bubble. One tip was also slightly cracked. All three of these phials contained traces of a black substance, and the leaf was partially or completely carbonized.

It was quite apparent that some crude tampering had occurred, which was indicative not of a miracle but, on the contrary, of some sort of fraud carried out by somebody in Moscogiuri's group. However, Civerra did not accept our suggestion of fraud, claiming that he placed more trust in his own external wax seals and that any deformity in the tubes was due to the "Holy Ghost's flame" in Moscogiuri's vision.

Despite Civerra's claim, we concluded that such flame-sealed glass test tubes—prepared with the few simple control procedures described above—could actually be a useful tool in the hands of researchers testing psychokinetic abilities.

As for Debora Moscogiuri, it appears that she still claims to have visions and periodically receive messages from the Virgin Mary, but strangely enough, materializations of oil inside containers no longer take place. l

Acknowledgment

This study would not have been possible without the work of Luigi Garlaschelli.

Carrying a Power Balance card in your pocket will supposedly improve your athletic performance and cure what ails you. The alleged mechanism ("frequencies" in an embedded hologram) is laughable pseudoscientific bunk.

Remember when professional golfers were wearing Q-ray bracelets to improve their game? The Q-ray folks recently had a run-in with the courts. They admitted their product was only a placebo but argued that it was acceptable to lie to elicit the placebo response. The judge disagreed: they were convicted of fraud, forced to pay back $16 million, and required to remove the deceptive claims from their advertising. Now they have a new competitor: Power Balance Performance Technology. Like the Q-ray bracelet, it is based on "resonance." It doesn't even have to come in contact with your body: one version is a card that you simply put in your pocket.

Power Balance representatives demonstrate their products

in sports stores at malls. They test your strength and balance and then give you a Power Balance card to hold or put in your pocket. When they retest you, you miraculously do better. There are some revealing videos on YouTube, including a short clip that shows the subject standing on one foot with arms outstretched. The salesman pushes down on the subject's arm near the wrist, and the subject starts to fall over. After the subject puts a Power Balance card in his pocket, the salesman repeats the test but this time pushes down near the elbow, creating a shorter lever arm that of course reduces the effect of the force applied, so the subject doesn't fall over. In other demonstrations, they use other simple biomechanical tricks like this to create false impressions of improved strength. The amount of force applied is subjective, both parties know when the card is in use, and they know what is expected to happen—it's a recipe for self-deception.

What's in these magic cards? I will quote at length from their Web site for the entertainment value:

POWER BALANCE Performance Technology has been embedded with naturally occurring frequencies found in nature that have been known to react positively with the body's energy field. This helps to promote balance, flexibility, strength and overall wellness.

For thousands of years, eastern medicine has been using the same techniques for personal wellness through finding things in nature that react positively with your body, such as rocks, minerals, crystals, etc. Through kinesiology we have learned that certain foods cause the body to react either positively or negatively as well. Although not all substances found in nature work the same on everyone, we have narrowed it down to a few that we believe are highly beneficial and have put them together to create Power Balance Performance Technology.

It's hard to argue with nature and the fact is that everything in nature resonates at a particular frequency. That is what keeps it all together. We react with frequency because we are a frequency. Most simply, we are a bunch of cells held together by frequency. If you hold processed sugar or a cell phone in your hand and hold your arm straight out to your side and have someone push your arm down while you resist, it goes down pretty easily because processed sugar and cellular telephones do not react positively with the human body. Basically, the frequencies in sugar and cell phones create a reaction that makes your body weaker. Adversely, if you put certain vitamins or minerals in your hand and do the same test with your arm, you will find it is much harder for that person to push your arm down. Your body's energy field likes things that are good for it and craves to be around those things. At Power Balance, we have taken a few of those items and through advances in technology, have been able to duplicate those positive energies and imprint them onto our holographic media.

Why Holograms? We use holograms because they are composed of Mylar—a polyester film used for imprinting music, movies, pictures, and other data. Thus, it was a natural fit. In fact, the hologram is so complex with such infinite depth and minimal surface area, that many companies are now using them as hard drives. Along those same lines, we felt that it would be a lot easier to get someone to put a hologram in there [sic] shoe rather then [sic] a Power Balance equipped rock or apple.

Power Balance products include a ten-pack of stick-on embedded holograms ($59.95), a pendant ($39.95), a wristband ($29.95), and an eight-pack of pocket cards ($59.95).

The company targets athletes, particularly surfers. According to numerous testimonials, Power Balance seems to improve performance. One surfer claims he can even sense the presence of the card: "I can feel it on me." Another testimonial is from Tommy Grunt, United States Marine Corps. Maybe Grunt is real, but ads for quack products have been known to feature fabricated testimonials, and I can easily imagine a copywriter putting tongue in cheek and creating a name like that to relieve the boredom. There are reports of the products' effectiveness in animals, from horses to birds. The products allegedly relieve headaches, menstrual pain, and all kinds of other symptoms. The testimonials give the impression that if you feel unwell in any way, the magic card will restore you to normal. If you already feel well, it will make you better than normal.

"A primitive form of this technology was discovered when someone, somewhere along the line, picked up a rock and felt something that reacted positively with his body." I don't doubt that someone believed he felt something, but I seriously doubt it was due to the frequency of the rock resonating with the frequency of his body.

For resonance to occur, something has to vibrate. You may be able to make a rock resonate, but the rock doesn't create its own vibrations. Crystalline structures can be made to vibrate. The tympanic membrane and the vocal cords vibrate, but the whole body doesn't. When a soprano wants to break a glass with her voice, she can first listen to the sound made by tapping it with a spoon; if she can match that sound frequency, the glass will resonate and possibly shatter. How can you tap a cat to see what its frequency is? Can you imagine a soprano shattering a cat?

This whole resonance and vibration business is pseudoscience emanating from the myth of the human energy field—not the kind of energy physicists measure but some vague life energy like the acupuncturists' qi, the chiropractors' Innate, and the imaginary fields that Therapeutic Touch practitioners claim they are smoothing down with their hands. "We are a frequency" and "We are a bunch of cells held together by frequency" and "Your body's energy field likes things that are good for it" are statements so incoherent, so much at odds with scientific knowledge, that they "aren't even wrong."

The definition of frequency is "the number of repetitions of a periodic process in a unit of time." A frequency can't exist in isolation. There has to be a periodic process, like a sound wave, a radio wave, a clock pendulum, or a train passing by at the rate of x boxcars per minute. The phrase "33 1/3 per minute" is meaningless: you can't have an rpm without an r. A periodic process can have a frequency, but an armadillo and a tomato can't. Neither a periodic process nor a person can "be" a frequency.

Pushing down on the arm is a bogus muscle testing technique known as applied kinesiology. It is supposedly used to diagnose allergies: if you hold a sealed vial of an allergen, your strength supposedly diminishes. It only works if the doctor and patient know what substance is being tested; when double-blind controls have been used, kinesiology has failed every test.

Omitting for a moment the crucial question "Frequencies of what?" how did the Power Balance creators determine which frequencies to use? "We have narrowed it down to a few that we believe are highly beneficial." Okay ... how exactly did they measure the frequencies, and what criteria did they use to narrow them down? I think the wording of the ad is revealing: the company says they "believe" they are highly beneficial, not that they have any evidence that they are—assuming there really are any frequencies and that they have somehow put them in a hologram. I e-mailed the company and asked simple questions like "How do you measure the frequency of a rock?" They didn't answer.

In online discussions, one man "tested" the product by having one hundred athletes try it, with no controls of any kind; not surprisingly, all of the athletes reported improvement. A man watching a demonstration suggested a real test, blinding the subject as to whether the card was present, but (not surprisingly) the salesman wouldn't cooperate.

This would be so simple to test properly. Take five Power Balance cards and five credit cards, put them in opaque envelopes, shuffle, number the envelopes 1 through 10, have a third party slip an envelope in the subject's pocket, and then challenge the salesman to tell which envelopes had the real card. I could not find evidence that they have ever done such a test, presumably because they know it would fail.

These products may actually do some good. Modern versions of an amulet or rabbit's foot (without harm to rabbits), they elicit a placebo response, giving people confidence and possibly making them try harder. They are not exorbitantly expensive and even come with a money-back guarantee.

The marketing is pure genius. If I were a professional scam artist, I don't think I could come up with anything better. The company has an impressive trick demonstration that easily fools most people. They spout a lot of pseudoscientific hooey that sounds impressive to the scientifically illiterate, but they are careful to make only vague claims that the Federal Trade Commission can't object to. The harmless products are inexpensive to manufacture, but the company charges enough to afford a money-back guarantee and still make money. They package the cheaper cards and stickers in multiples so they can charge more, but the prices are still low enough that the average person is willing to take a chance. Who knows what is actually in the products? If it were my scam, I'd put in any old hologram or none at all. No one is likely to investigate your production line to see how you get all those "beneficial frequencies" into the Mylar.

Tell me you use the Power Balance card and it makes you feel better, and I can readily believe you. Tell me your performance improves when you carry it, and I will believe you. But that won't convince me that the improvement has anything to do with bioresonating frequencies in the holograms—or even with the cards themselves.

It's like the tooth fairy. Tell me money appears under your pillow, and I will believe you. But that won't convince me that the tooth fairy did it.

The tooth fairy phenomenon is easily explained by human psychology and parental behavior. The Power Balance phenomenon is easily explained by suggestion, confirmation bias, the placebo response, and other well-known aspects of human psychology that conspire to persuade people that ineffective things work.

Before writing this article, I discussed with CSI Research Fellow Benjamin Radford whether the Committee for Skeptical Inquiry might want to do a simple double-blind test. We decided not to because it is just too silly to bother with. As Radford put it, "This sort of scientific testing should be done by the company; it is not the skeptics' job to spend time and money testing outlandish claims for which no reliable evidence has been offered."

We're not going to bother setting up a video camera to catch the tooth fairy either.

The evidence provided by Stan Romanek that purports to prove he has been repeatedly visited or contacted by extraterrestrials is all of a suspicious nature.

I was queried by ABC News about an alien video that subsequently aired on the ABC show Primetime: The Outsiders (August 18, 2009). The documentary focused on the personal experiences of a few people who believe they have been abducted by aliens, as well as on certain physical evidence, offered by one alleged abductee, that purports to prove alien visitation.

The reported experiences were consistent with other abductees' reports. Many of the abductees have simply had common "waking dreams," which occur in the borderland between wakefulness and sleep. Others have been hypnotized by alien-abduction gurus like the late Dr. John Mack and therefore have merely gone on a trip to Fantasyland that can conjure up false memories. Some of the more elaborate experiences happened to subjects (like Whitley Strieber, author of Communion) who, though sane and normal, nevertheless exhibit many of the traits of fantasy-prone personalities: being easily hypnotized, having vivid memories, experiencing intense dreams, and having out-of-body experiences, among others (Nickell 2007, 251–258; Baker 1987–88). A few alleged abductees may be psychotic, while others seem so craving of attention that they have turned to hoaxing.

The physical evidence was offered by Stan Romanek, forty-six, who claims to have had contact with extraterrestrials since 2000. Indeed, if he is to be believed, he serves as a virtual magnet for extraterrestrial attention and has been getting quite a bit of terrestrial notice too—not all of it favorable. Living on disability income, he spends much time actively promoting the notion that aliens are fascinated by him. His obsession began when he caught on video a UFO that was witnessed by others at a park on the outskirts of Denver. Romanek also offers a video of an alien peering in his window and an X-ray showing an alien "implant" in his leg.

On Primetime: The Outsiders he was supposedly hypnotized by Leo Sprinkle, a psychologist who studies abductees and contactees. (Formerly of the University of Wisconsin, Sprinkle was asked to leave his position when colleagues found his work unprofessional and unscientific [Chang and Dubreuil 2009].) Under hypnosis, Romanek, who claims to have only a fifth-grade proficiency in math, wrote out a high-order mathematical sequence known as Drake's equation (an astrophysics formula approximating the number of planets in the Milky Way galaxy that could have intelligent life) (Chang and Dubreuil 2009).

To a professional mathematician, the equation feat seemed no more than memorization by an amateur. When ABC News asked Romanek for an independent medical assessment of his alleged implant, he claimed it had suddenly disappeared (Chang and Dubreuil 2009).1 As for the videotaped alien, which Romanek named "Boo," a reporter appropriately described it as resembling "one of the glow-in-the-dark heads I got when I was in Roswell, New Mexico" (Meadow 2009). It certainly embodies the stereotypical likeness—the big-eyed, big-headed little humanoid that has evolved in popular culture and is seen in toy stores (Nickell 2001, 160–163). Romanek's alien provoked many parodies on the Internet.

Romanek's wife seems extraordinarily credulous, though she insists she is not. It is difficult to keep a straight face when you hear her say: "... when all your [TV] remotes in your house disappear for three days and you have searched everywhere, and then you wake up the next morning and they're all lined up on the counter, that's something I can't explain when I've searched for them." Less naive people would surely look not to aliens but to nearby terrestrial beings for suspects.

To assess Romanek's UFO video, I turned to my colleague Tom Flynn, a video expert, who treated me to a frame-by-frame analysis. He noted that the object was below clouds and appeared to pick up "illumination from ground sources such as street lights," suggesting it was rather low-flying and small, which was further suggested by its apparent rate of motion relative to the camera. As Flynn explained:

A very large object would have to move at a very high rate of speed to display the apparent motion seen in this clip. A smaller object, which would be correspondingly closer to the camera, could display the same apparent rate of motion if it were simply drifting on a modest breeze, particularly if it had been quite close to the camera at the beginning of the shot.

Flynn concluded:

Given the modest amount of visual evidence, many other explanations are possible. But in my opinion the imagery of this just over 11-second clip is consistent with a translucent, slightly underinflated balloon between 2' and 6' in diameter that carries or contains two light sources: one circular whitish constant light source, and one flashing red strobe with a period of 8–10 flashes per second, released from a position to the left of camera prior to the shot and allowed to drift overhead on a wind blowing from the videographer's left.

He characterized the red flashing light as "similar to emergency strobes found on some toys, camping lanterns, and the like" (Flynn 2009; see figures 1–3).

In short, the evidence provided by Stan Romanek that purports to prove he has been repeatedly visited or contacted by extraterrestrials is all of a doubtful, even suspicious, nature. I cannot distinguish it from hoaxing. Romanek, who is reportedly working on a feature film, asks of the entities, "Are they from a different planet? I can't tell you. I know they're not human, whatever they are" (qtd. in Chang and Dubreuil 2009). The evidence would appear to indicate that they, and their craft, hail from the familiar planet Latex. l

Acknowledgments

I am grateful to CFI colleagues Henry Huber, Tom Flynn, and Tim Binga for their help with this investigation.

Note

1. For more on alien implants, see Nickell 2001, 204–205.

References

Baker, Robert A. 1987–88. The aliens among us: Hypnotic regression revisited. Skeptical Inquirer 12(2) (Winter): 147–162.

Chang, Juju, and Jim Dubreuil. 2009. Man claims aliens send him messages. ABC News. Available online. (accessed August 18, 2009).

Flynn, Tom. 2009. Report to Joe Nickell, August 25.

Meadow, James. 2008. Rocky Mountain News report on Larry King Live, May 30.

Nickell, Joe. 2001. Real-Life X-Files: Investigating the Paranormal. Lexington, KY: University Press of Kentucky.

———. 2007. Adventures in Paranormal Investigation. Lexington, KY: University Press of Kentucky.

Interview with Scott Crocker

Strangely enough, the ivory-bill has captured the imagination of people the world over for a very long time.

The chance sighting in Arkansas's Cache River National Wildlife Refuge of a presumed extinct woodpecker led to a 2005 scientific expedition that confirmed that the birds still live. The ivory-billed woodpecker (Campephilus principalis), last known to exist in 1944, was supposedly sighted in eastern Arkansas in 2004. A blurry video clip showed the bird's distinctive size and markings. "The bird captured on video is clearly an ivory-billed woodpecker. Amazingly, America may have another chance to protect the future of this spectacular bird and the awesome forests in which it lives," said John Fitzpatrick, director of the Cornell Laboratory of Ornithology.

The discovery of the bird spawned international headlines and an article in the journal Science (see "Rare Woodpecker, Presumed Extinct, Found in Arkansas," SI, March/April 2006). The rediscovery was also trumpeted by believers in Bigfoot and lake monsters as proof that animals thought long extinct may still exist.

Yet after five years of searching (at a cost of over $10 million) the ivory-billed woodpecker's existence remains unproven. Not a single bird has been found. A discovery once touted worldwide as a hopeful environmental miracle has turned into a complex and fascinating tale of environmentalism, anecdotal evidence, and scientific debate. What happened is the subject of a new documentary film titled Ghost Bird. I interviewed the film's director, Scott Crocker.

Benjamin Radford Why was the story of the rediscovery of an obscure woodpecker such a big deal?

Scott Crocker Strangely enough, the ivory-bill has captured the imagination of people the world over for a very long time. They were truly striking black and white woodpeckers, the males having bright red crests, and they were once the largest woodpeckers in North America. Full grown they were two feet tall and had a wingspan of nearly three feet.

The alleged rediscovery of the ivory-billed woodpecker in 2005 made headlines around the world. That a species of this magnitude had returned from the dead after being presumed extinct for over half a century was both miraculous and astonishing. A kayaker's sighting was confirmed by a search team from Cornell University's Laboratory of Ornithology, one of the world's leading institutions devoted to studying all things avian. Their rediscovery in Arkansas was perceived as a kind of environmental miracle suggesting that mankind was getting a second chance to save a species he had singlehandedly exterminated. And just maybe, the efforts of conservationists were beginning to turn the tide of human-caused extinctions.

Radford The tiny town of Brinkley, Arkansas, was the epicenter of the furor over the ivory-bill. What effect did all this international publicity have on the town?

Crocker Brinkley played a central role in both receiving and reinforcing the rediscovery hype, partly because they had nothing to lose.

Radford Many towns that have a local "monster" are quick to capitalize on their local mystery (for example, Bluff Creek, California, has a booming Bigfoot-related business, and Inverness, Scotland, earns a lot of money from Nessie tourism). Brinkley, quite understandably, did the same thing.

Crocker They tried. While some locals were quick to capitalize on the publicity by selling ivory-bill burgers, haircuts, and T-shirts, the influx of birders and their fat wallets never quite materialized. The world's only ivory-billed woodpecker gift shop has closed, and there was only one Annual Ivory-bill Celebration in Brinkley's new convention center.

Radford How did you get involved in making Ghost Bird?

Crocker I heard about the ivory-bill's rediscovery like everyone else, when then-Secretary of the Interior Gale Norton announced it had been seen in Arkansas. And as fascinating as the rediscovery was, I was equally intrigued by the descriptions of the yearlong top-secret search and the many hours birders spent deep in the snake- and mosquito-infested cypress swamps of Arkansas waiting for a glimpse of the largest and rarest woodpecker in North America. It sounded like a Samuel Becket play, Waiting for a Woodpecker.

I didn't get personally pulled into the story until the following September. I was attending the Jackson Hole Wildlife Film Festival where I met a cameraman who had practically lived in those swamps waiting for the ultimate money shot. Fourteen months later he emerged with a couple brief sightings and a few compelling bird sounds only to discover his second wife had left him. I thought, wow, these people are seriously obsessed. I needed to find out why. While I didn't go into it as a skeptic, I also didn't unquestioningly accept everything the search team announced or claimed about their very blurry video of something flying through the swamp.

Radford One person in your film described the debate as about "hope versus skepticism."

Crocker That was [bird expert] David Sibley's distillation of the whole issue, and I think he hit the nail on the head. The sightings by top ornithologists, their scientific documentation, and the controlled media campaign announcing the ivory-bill's rediscovery created an atmosphere that was not unlike G.W. Bush's doctrine of "Either you are with us or you are against us."

Radford That doesn't sound like open, scientific debate.

Crocker Well, some of that exclusiveness came down to the good intentions of protecting the species from being "loved to death" by birders. However, it was also driven by the need to raise money and acquire local land inexpensively. Questioning the evidence was a threat to the $10 million in federal, state, and private money the search team raised. Questioning the sightings also meant questioning the integrity of the ornithologists and birders who made those sightings—and the birding community heavily relies on individual integrity. Since the search scientists didn't invite any real critique of their findings, in the end you were either on board and hopeful, or you were a skeptical outsider. And no one wanted this iconic bird's rediscovery not to be true.

Radford Political grandstanding and bird expert squabbles aside, the ivory-bill's rediscovery was given scientific credibility by a high-profile cover article in Science, right?

Crocker Absolutely. The Science article in many ways is the lynchpin to all of this. Without that article and the magazine's enormous clout, I don't think the rediscovery would have had much traction. That their editorial staff seemingly looked the other way and gave the ornithologists the benefit of the doubt raises some of the more interesting questions about the whole rediscovery fiasco. How much of this had to do with selling magazine issues? How much had to do with everyone hitching a ride on a career-making moment?

Radford What does the story of the woodpecker say about how science works?

Crocker I think the most disturbing message of the rediscovery is the central role money plays in driving scientific inquiry and research. One academic who has been tracking this trend described to me the process of acquiring funding for research as being akin to throwing spaghetti at the wall: whatever project sticks gets the green light. This "stickiness factor" of proposals is often determined by very unscientific agendas having more to do with commercial and public relation interests.

Radford How did the search for the ivory-bill become so politicized, with agendas and egos?

Crocker Territorial squabbles are of course nothing new to academics. And there was a healthy amount of slinging from both sides in the ivory-bill debate. However, the real anger surrounded the redirection of scarce funding from existing endangered species recovery programs to the search for a ghost bird. It's one thing to run around in the swamp seeing things. It's another thing entirely to do that with money "rediscovered" in the research accounts of other scientists. This brings us back to the legacy of the Bush administration: they promised $10 million in funding for the search but then robbed Peter to pay Paul; it wasn't new funding.

Radford What's been the response to your film? Is there any current funding for the search, or is it effectively dead?

Crocker Cornell continues to maintain that they saw an ivory-bill and documented it on video. They admit that the bird has not been quite as "persistent" as they had hoped. As of this year they are no longer actively searching for the bird in Arkansas, though they were one of two groups looking in Florida last year.

Radford Does it matter if the ivory-billed woodpecker exists or not?

Crocker If there's only one of them, no, not really. I think what matters is that we collectively come to grips with taking responsibility for the species mankind is causing to go extinct. Ultimately, perhaps the most lasting significance of the ivory-bill is how it has become a mirror that reflects back to us our difficult relationship to the natural world and our uncertain place in it. We can look deeper into that mirror and change how we inhabit the planet, or we can look away and go about our business as usual.

Ghost Bird opened in New York City at the end of March for a week at Anthology Film Archives. The DVD should be available in June; find more details at www.GhostBirdMovie.com.

Benjamin Radford is managing editor of the Skeptical Inquirer and an avid fan of documentary films.

This Online Extra is a follow-up to the article “War of the Weasels” from the May/June 2010 issue of the Skeptical Inquirer (Volume 34.3, May/June 2010). The print article discusses the use of a genetic algorithm (GA) to solve tricky math problems and demonstrates that no specific “target” is required for such algorithms, contra the interminable creationist attacks on the “Weasel” simulation discussed in Richard Dawkins's book The Blind Watchmaker. The problem I developed the GA for is called Steiner's Problem; it involves finding the shortest straight-line-segment networks connecting an array of given fixed points. This problem provides a miniature digital playground on the very edge of complexity.

I first became interested in Steiner networks because of their connection to minimal surfaces and to physical analogs like soap films. These are useful in some minimization problems because surface tension in the soap films acts to minimize the total area of film. This property allows Steiner network problems to be solved directly with soap films. First, two parallel clear plates are connected by posts that represent the nodes or “cities” of the problem. Then, the assembly is dipped into a solution of soapy water and then carefully withdrawn to produce the Steiner solution (one hopes).

(Hover over images for more detail)

Figure 1. Soap film realization of Steiner Solution for four-node system.

Here is a soap-film realization of the five-node system. Seven segments are joined with three variable nodes to make the compact network shown—the proper Steiner solution for the five-node system. Again, the segments meet at 120-degree angles.

Figure 2. Soap film realization of Steiner Solution for five-node system.

It wasn’t until I started investigating whether some of the MacGyver solutions could also be realized with soap films that things really got interesting. I quickly found that several of the configurations that evolved from the genetic algorithm could also be obtained with soap films, simply by pulling the parallel plates out of the soap solution at angles other than horizontal. A soap film incarnation of one of the MacGyver shapes appears below.

Figure 3. Soap film realization of “MacGyver” Solution for five-node system.

Not all of the MacGyvers could be obtained with soap films, however. The shape below, which I named the “Face Plant,” features four segments meeting at a common point. While this presents no problem for DNA representations of solutions, it is almost impossible in real soap films, as the junction of four films is invariably a very unstable equilibrium. In soap films, such junctions of four segments will quickly resolve into a bow-tie shape as typified in the solution to a simple four-node Steiner system. The Face Plant turned out to be a MacGyver solution that could easily exist in the genetic algorithm but could not be realized with minimal-surface soap films.

Figure 4. The “Face Plant”: a viable genetic algorithm solution for a five-node system.

As if that wasn’t strange enough, I soon stumbled on the “Doggie”—a stable soap film configuration that never appeared during the genetic algorithms simulations. Even the formal (but topologically tricky) Steiner solution popped out one of two hundred runs on average—why did the Doggie never appear?

Figure 5. The “Doggie”: A viable soap film solution for a five-node system.

After several frustrated attempts at Doggie evolution, I decided to go ahead and do what Dembski implies I am doing for all such shapes—deliberately perform some “genetic engineering” to “front-load” the system with a specified solution. Accordingly, I deduced the DNA configuration for a typical Doggie and forced this particular organism to be present as one individual of the very first generation of a simulation.

“the Doggie” length = 1403

Figure 6. The “Doggie”: a nonviable genetic algorithm solution for a five-node system.

Sure enough, the Doggie was much more fit than most members of the initial (random) population and persisted for several generations. However, at 150 to 200 units longer than all of the MacGyver solutions, it was quickly out-competed and forced to extinction by such fitter solutions. After a dozen generations or so, the Doggie was simply wiped out by the competition.

Had I actually been feeding the proper Steiner solution into the algorithm—“front-loading” in Dembski’s parlance—it would have always triumphed, and I would never have found the bizarre and wonderful world of MacGyver also-rans. The same boring result would also have been obtained had I defined “fitness” as deviation from a single, specific “target”—the proper Steiner solution itself. Either way, I wouldn’t have found that some (but not all) of these new structures could be realized with soap films, and I wouldn’t have found that some stable soap film configurations are far longer than the minimum possible and are not retained in evolutionary algorithms. As I said, I have never been as astonished at the unexpected output of one of my digital programs.

As the ID community flailed about trying to answer the Design Challenge, reader Sam Garret commented, “Can’t they just figure it out with soap bubbles? Assuming they can remember the way to the lab, of course.” Alas, such was not the case.

Notes

The "War of the Weasels" on the Web: http://pandasthumb.org/archives/evolution/evomath

The fact that either of these authors felt the need to write their respective books is, in a way, somewhat bizarre and sad. Charles Darwin published his book On the Origin of Species in 1859; the world has had 150 years to digest and understand evolution, and evidence for Darwin’s theory has grown more robust with each passing year. In an ideal world, Dawkins and Loxton would be chided for wasting their time and effort pointing out the patently self-evident. What’s next, a book explaining to the public that the sun shines upon them every day?

And yet polls and surveys show that a significant number of people (around 40 percent, but depending on the exact poll question) have doubts about evolution. Some of them are creationists, but many others simply have never had evolution explained to them correctly.

Evolution by natural selection is not necessarily clear or intuitive. Evolution is not inherently obvious; it is a slow, complex process with many nuances. Whether stunted by a poor educational system or religious fundamentalists, it is a minor tragedy that one of the greatest scientific ideas in history remains the subject of dispute.

That is why books like The Greatest Show on Earth and Evolution are important. The former is meant for educated adults who want complete, well-rounded information on the evidence for evolution; the latter is aimed at children and teens who want a solid understanding of evolution’s fundamentals. Each is very appropriate for its audience, and paired together both books make a complete evolution literacy package (along with On the Origin of Species, which remains very readable). To be honest, I’ve not had a chance to more than skim Dawkins’s 460-page tome, though I expect it’s excellent. Loxton’s book, with only fifty-five pages and enticing full-color art on every page, is more accessible, and I’ll focus on that.

Loxton has a lot of ground to cover, and he begins by noting that different fossils are found in different geological strata—a fact that suggested to early researchers that many now-extinct animals had once roamed the planet (and much longer ago than most people could imagine). Evolution goes on to touch on a wide variety of subjects related to evolution, from DNA to the alleged “living dinosaur” mokele-mbembe. Along the way, new concepts such as species and mutation are introduced, often in the form of posed questions. Charles Darwin’s experiments are briefly described, including his research into avian inbreeding and the variations in beaks in isolated populations of Galapagos island finches. The elements of evolution are explained in terms that are neither dumbed-down nor too complex for its target audience.

Loxton, editor of Junior Skeptic, also shows off his considerable illustration skills. The book is clearly written for children, and eye-catching graphics are of course a necessity. Every page has one or more enticing, full-color images illustrating everything from dinosaurs to the bird-dinosaur Archaeopteryx to cute, flirty little zebra-like things called Zooks. This helps reinforce the important concept that evolution is not a stale, dry theory dusted off from irrelevant history or science books but instead a real, active process occurring all around us at this very moment. It’s rare to find such an accessible, dynamic treatment of the subject of evolution.

Evolution also wisely anticipates and addresses some of the most common anti-evolution fallacies (such as that the eye is too complex to have evolved naturally). This feature alone makes the book better than other simplified descriptions of evolution because it inoculates readers against bogus creationist arguments they may hear but would be otherwise unable to answer.

While the content of the book is very good, a few elements could have used better organization. For example, there are about a dozen sections that begin with a question. This is a useful way to present information, but the questions appear next to illustrated oval portraits of people whose relevance to the book is unclear. The questions themselves are fine, but I found the associations with anonymous portraits confusing at first. It might have been more effective if the book had begun with two or three recurring characters who would be asking questions on behalf of the reader throughout the book, instead of introducing a different, apparently random face each time. The book also needed a references or further reading section. Though Richard Dawkins is quoted several times in the text, for example, none of his books or articles are mentioned or referenced. Overall, however, these minor issues don’t detract from the book’s presentation and message.

I hope that 150 years from now books on evolution, such as those by Dawkins and Loxton, will be considered obsolete, a redundant parroting of basic facts that every schoolchild knows.

Until then, the world is sorely in need of high-quality, accessible science and skeptical books for teens and children, and Loxton’s book is an excellent and long-overdue introduction to evolution.