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The Rancorous Asteroid Impact vs. Deccan Traps Volcanism Dinosaur Extinction Debate

Dewey McLean

So Dewey is now a forgotten person in the field, or when he is remembered, it is only for a few good laughs, at the cocktail party at the end of the Deweyless meeting . . . . I’m sorry to say I see you going down the Dewey McLean lane.

—Luis Alvarez, letter to Robert Jastrow, head of NASA's Goddard Institute for Space Studies in New York; founder, George C. Marshall Institute, 1984

If the president of the college had asked me what I thought about Dewey McLean, I’d say he’s a weak sister. I thought he’d been knocked out of the ball game and had just disappeared, because nobody invites him to conferences anymore.

–Luis Alvarez, The New York Times, 19 January 1988

In your Luis Alvarez biographical memoir published on the National Academy of Sciences website you stated: "Luie could be devastating when publicly demolishing a wrong result. Sometimes he was personally gracious, as with his critique of Buford Price's magnetic monopole claim, and at other times not, as with Dewey McLean's volcanism explanation for the K-T extinction."

–Excerpt from my Open Letter to W. Peter Trower in response to his Luis Walter Alvarez 1911-1988 Biographical Memoir (2009)

Operating in a science you do not comprehend, you publicly insult paleontologists. In the New York Times (1/19/88) you abased paleontologists as "not very good scientists...more like stamp collectors," and attacked opponents by name as "weak sister," "incompetent," and "publishing scientific nonsense." In your own field, you have stated "There is no democracy in physics. We can't say that some second-rate guy has as much right to opinion as Fermi" (in Greenberg, The Politics of Pure Science, 1967, p. 43). Now, you would deny paleontologists the right to opinion in their own field. Some tell of threats to silence them.

–Excerpt from my Open Letter to Luis Alvarez, 1988

. . . the member of a mature scientific community is, like the typical character of Orwell's 1984, the victim of a history rewritten by the powers that be.

–Thomas S. Kuhn, The Structure of Scientific Revolutions, 1970.


K-TEC II meeting: Violent Beginning of the K-T Impact vs. Volcanism Debate

19 May 1981. K–TEC II (Cretaceous-Tertiary Environmental Change) meeting, Ottawa, Canada. Beginning of the Cretaceous–Tertiary asteroid impact vs. Deccan Traps volcanism K-T extinctions debate.

Luis Alvarez, Nobel Laureate author of the theory that a giant asteroid slammed into earth 65 million years ago triggering a mass extinction that wiped out much of earth’s life, including the dinosaurs, glared red–faced at me across the tables that separated us. He and his Berkeley impact team had started off the K-TEC II meeting by presenting evidence supporting their theory (Alvarez et al., 1980) and already, before the first coffee break, contflict was erupting. The primary evidence for the Alvarez impact theory was enrichment of the chemical, iridium, in rock strata at the geological Cretaceous-Tertiary (K–T) boundary. Some extraterrestrial objects are enriched in iridium, and Alvarez claimed that the K-T boundary (KTB) iridium was proof of impact. I did not agree. I argued that the KTB iridium had likely been released onto earth's surface by volcanism.

Four months earlier, at the January 1981 meeting of the American Association for the Advancement of Science (McLean, 1981a), I had proposed that the Deccan Traps volcanism in India, one of the greatest episodes of flood basalt volcanism in earth history, had erupted at K-T boundary time, flooding earth’s surface with the greenhouse gas, carbon dioxide, triggering a perturbation of the carbon cycle which caused the K-T mass extinctions, and released the iridium onto earth’s surface. My research, by providing an earthly source for the iridium, equivocated the Alvarez asteroid impact theory. As I presented my work at the K-TEC II meeting, Luis Alvarez became increasingly upset with me.

Luis Alvarez had big stakes riding on his impact theory. I would learn later that in June 1980, the same month of publication of the Alvarez theory, NASA (the National Aeronautics and Space Administration) had chosen it to be the basis of a new program known as Project Spacewatch. At that time, President Ronald Reagan was putting the budgetary axe to the space agencies. The Alvarez impact theory which evoked death from the heavens--imminent, unavoidable, catastrophic, horrifying mass extinctions of life on earth--was just what the space agencies needed to rejuvenate them via new funding and career opportunities. Alvarez, as originator of the impact theory, and as a major player in this vast new enterprise of saving our civilization from future impacts, had motivation for being upset over the equivocation of his impact theory. As I discussed how the Deccan Traps volcanism likely released the K-T iridium onto earth’s surface, Alvarez leaned his tall frame over the table toward me, his face flushed and his eyes like those of a goshawk fixed on a prey--me. He was obviously upset with my attributing the K-T iridium spike--the basis for his impact theory--to the Deccan Traps volcanism.

Dale Russell, convener of the K–TEC II meeting, called for a coffee break. The other 23 participants headed for the coffee urn. Alvarez headed for me.

"Dewey, I want to talk with you," Luis Alvarez said, "directing" me to a corner across the large room away from the other scientists. We stared at each other briefly.

"Do you plan to publicly oppose our asteroid?" Alvarez said.

"Dr. Alvarez, I’ve been working on the K–T for a long time," I said. "I published my greenhouse theory two years before you published your asteroid theory."

"Let me warn you," he said. "Buford Price tried to oppose me, and when I finished with him, the scientific community pays no more attention to Buford Price."  (I had never heard of a Buford Price prior to Alvarez' comment).

"Dr. Alvarez, I did the first work showing that greenhouses can cause global extinctions," I said. "We’re facing a possible greenhouse today. I have an obligation to continue my work...."

"You’ve been warned," he said, turning abruptly, and striding rapidly to where the other scientists were having coffee without ever looking back.

I wrote down the words of our exchange.

That afternoon, another member of the Alvarez impact, Walter Alvarez, son of the Nobelist, Luis Alvarez, told me, "Dewey, count them, 24 are with us. You are all alone. If you continue to oppose us, you will wind up being the most isolated scientist on this planet."  I wrote down Walter’s words.

The Alvarezes, it was clear, would deal harshly with anyone whose own research stood in the way of their agendas, even to the point of trying to intimidate them into silence.

That evening, a young scientist whom I met at the K–TEC II meeting, one who would later become a prominent impactor, told me, "Dewey, you’re here to be won over, or run over." Here’s what journalist Pat Ohlendorf said about the K-TEC II meeting in his 25 May 1981 article in The Globe and Mail titled "Several reasons for extinctions: scientists":

There were probably several reasons for the extinctions of 75 percent of the animal and plant species 65 million years ago, but a major cause was an object from space, a group of scientists meeting in Ottawa has decided.

Of course their general agreement is not surprising, because all but one of the 25 participant–astronomers, physicists, geologists and paleontologists from North America and Britain and elsewhere in Europe–already favored the possibility of an extraterrestrial event and rapid extinctions.

All in all, 24 out of 25 participants were in "violent agreement" as Luis Alvarez put it.

The lone member of the opposition was Virginia paleontologist Dewey McLean.

Aftermath to the Ottawa K-TEC II Meeting

Soon after the K-TEC II meeting, Luis Alvarez instituted a widespread vendetta against me that was dedicated to wrecking my Deccan Traps K-T extinction theory. I next met Luis Alvarez at the Snowbird I meeting titled "Large Body Impacts and Terrestrial Evolution: Geological, Climatological, and Biological Implications," which was held at Snowbird, Utah, from October 19-22, 1981. Prior to my talk, Dale Russell, curator of vertebrate fossils at the National Museum of Canada in Ottawa, Canada, told me that Luis Alvarez was circulating among the scientists at the meeting badmouthing me.

Russell was the one who had invited me to attend the Ottawa K-TEC II meeting in which 24 of the 25 invited participants were already in "violent agreement" with Alvarez impact theory. In fact, the meeting seemed to have been designed as a rubber stamp of approval for the Alvarez theory. Later, at other scientific meetings, other scientists told me about Alvarez' widespread political undermining of both my research and me personally.

Most insidious of all were the vicious politics by Luis Alvarez and some of his paleobiological followers that were injected into the Virginia Tech Department of Geological Sciences where I worked with devastating impact upon my career and health. So severely was I harassed by my department head who was distressed that Alvarez, a Nobelist, was publicly criticizing me that he tried to divert me away from my K-T research. I was to learn that my most trusted departmental colleague was, in fact, bringing vicious politics into the department and feeding them to the department head and other faculty colleagues. I became a literal pariah in the department. The stresses I was subjected to because of my K-T research ground me down.

David Wones, a petrologist, was Chairman of our Department. He was the best boss I had ever known. He was supportive of my K-T volcanism–extinctions work, insisted that I attend the 1981 Snowbird I conference, and even paid my way. He even hinted at joining me in my research. Wones’ 1/13/81 Faculty Activities Report to the Dean stated, “Dewey is one of the creative and original thinkers in the department . . . If he is correct in his analysis of fossil extinctions, the department will have housed one of the major figures of our time.” And, “Dewey has been most cooperative with me.” I adored David Wones.

Then, my most trusted departmental colleague--an old buddy of two paleontologists who openly promoted the Alvarez impact theory, and wanted to use it to develop new theory that impacts drive bioevolution on our planet--was promoted to full professor, and got on the Executive Committee. One of those old buddies brought my departmental colleague and Luis Alvarez together at a meeting in California. My relationship with Chairman Wones deteriorated quickly and badly.

By 1/12/83, Wones was so distressed with me that his Faculty Activities Report noted, “Dewey McLean remains the least collegial of the faculty in the Geological Sciences.” Wones would get angry with me for reasons I could not fathom and, when he saw me, might turn red–faced, and utter scathing remarks. Finally—I had “no future here.” And should “look elsewhere.” Wones had “no time” to discuss what was wrong.

A friendly Assistant Dean of Arts and Sciences confided in me that "someone" could get fired because of his involvement with the K-T debate. I was the only one on campus who was working on the K-T. The vicious subversive political campaign to destroy me and my career because of my opposition to the Alvarez impact theory was psychologically crushing me, and made even more devastating because I had no way to confront it.

Then, one day, quite by accident, I overheard my trusted colleague scathingly discussing my research with the Chairman of our Department. I later confronted the Chairman and learned that two prominent paleontologists--the old buddies of my colleague--in addition to Luis Alvarez, had influenced him against me. By threatening to bring lawsuit against the Chairman for the psychological trauma he had put me through, I found out who the paleontologists were.

What happened to me was extremely unfair. In my undergraduate teaching, I had won four Teaching Excellent Awards, and my graduate research program had been cited by the Association of Stratigraphic Palynologists as second only to the program of my mentor, Bill Evitt, at Stanford University. I was being politically attacked because of vicious politics regarding my K-T work that were meant to undermine and wreck my theory.

Stresses because of those unfair politics and "dirty tricks" took their toll. Horrific pain woke me one January 1984 morning. Nearly every joint in my body was inflammed and so excruciatingly painful that I could barely function. That malady lasted through the year of 1984, causing me at times to be a virtual invalid. I developed a Pavlovian response to the K-T such that I was able to work on a field of science that I had pioneered only with the greatest of difficulty, fearing that stresses might trigger relapse of my health. I never recovered physically or psychologically from that ordeal. It essentially wrecked my scientific career. To understand, at least partially, what happened to me, please read my Letter to Luis Alvarez, my Letter to David Raup, my Letter to Stephen J. Gould, and my Open Letter to Peter Trower.

Death from the Heavens: The Big Sell

In June 1980, the same month as publication of the Alvarez theory, NASA adopted it as the basis for its Spacewatch program. Promises of new monies for the space sciences, new careers, honors, and glory were in the air. Physicists, chemists, astronomers, astrophysicists, journalists, popularizers of science, and historians, who suddenly discovered Earth's fossil record as a rich plum ripe for the picking, raced into K-T science like miners flooding to a new gold strike. Some meant to take over K-T science for their own agendas, in the process playing rough and dirty with scientists who had spent much of their careers doing K-T research. The media blitz—and the Big Sell—was on.

As part of the sales pitch that an impact caused the K-T mass extinction, the Alvarez theory is often presented as a literal truth. Luis Alvarez made the following claims: "1) that the asteroid hit, and 2) that the impact triggered the extinction of much of the life in the sea, are no longer debatable points" (talk, Nat. Acad. Sci., 4/18/82; pub. Proc., 1983: 80, 627-642). In the New York Times (1/19/88), he stated, "There isn't any debate." In Physics Today (1988: 41, 118-120), he stated "it is no longer appropriate to say, 'Whether this impact was the primary cause for the extinction of the dinosaurs is still an open question'...that question has been thoroughly closed off in the past several years." His public media blitz has been rich in "everybody believes...."

In fact, the impact theory has such big holes in it that an Argentinosaurus could be flung cartwheeling through it without touching anything. So does the volcano theory. Today, both theories are but frameworks for future research. At the beginning of the debate in 1981, and for some time after, the impact and volcano theories were evenly matched. But quickly, the corrupting politics of science and journalism began to overwhelm the science, and favor began to shift toward the Alvarez impact theory. Paleontologists who had spent much of their careers investigating the K-T extinctions found themselves under attack as being slow fellows who did not know how to evaluate earth history--but impactors who had no publication records indicating that they knew much of anything about the K-T data base--did.

Editors and journalists at the prestigious publishing houses of Nature and Science, the most popular and widely read scientific magazines in the world, embraced the Alvarez theory. In 1984, at a time when the impact versus volcano K-T extinction debate had hardly begun, the editor of Nature, John Maddox, stated (Nature, 1984, v. 308, p. 685) that, “Luiz and Walter Alvarez appear to have proved their original case that the massive extinction at the end of the Cretaceous period was caused by the impact of some extraterrestrial object.” Some scientists, who were not supportive of the Alvarez theory, claimed little support of their manuscripts by Nature editorial. Same for Science magazine.

For Science, its favoritism of the Alvarez theory, and the literal blanking out of the volcano side by Richard Kerr, a staff writer who covered the K-T debate for Science, are little short of shameful. It was not until 1991, ten years into the debate, that Kerr informed the readers of Science magazine that volcanism may have been a factor in the K-T extinctions. Please see Science Coverage of the K-T Debate, and my Letter to Richard Kerr.

The "K-T Letters"

Beginning with the 1981 K-TEC II meeting, I took copious notes of events and conversations, and wrote many letters, that I call the “K-T Letters,” to other people. They document historical aspects of the K–T debate, that might otherwise be buried in the dusts of the history of the K-T debate. Some went to political and scientific leaders, calling to their attention corrupting aspects of K-T science. I called for the development of a meaningful Code of Ethics for science, and an Appellate Commission that might, in the future, prevent destructive politics from overwhelming the processes of science. Others were appeals for help, and others to record the history of events and circumstances. Those letters went to the President of the National Academy of Sciences; members of the National Academy of Sciences who were helping promote the Alvarez theory; Nobel Laureates; Presidents, and President Elects of the American Association for the Advancement of Science (AAAS); editors of Science, Nature, Mosaic and other magazines; staff writers, and members of the Science editorial board; the Director of the National Science Foundation; popularizers of science; the self–appointed historian of the K–T debate; members of the U. S. House of Representatives, and Senators; and many others. The K-T Letters are an integral part of the historical development of the K-T scientific debate. Some detail actions by individuals that served to corrupt K-T science. I include some K-T Letters in this website.