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19 May 1981. K–TEC II (Cretaceous-Tertiary Environmental Change II) meeting, Ottawa, Canada. Day one of the Cretaceous–Tertiary (K–T) asteroid impact versus volcano extinctions debate (Russell and Rice, 1982).

Luis Alvarez, Nobel Laureate, glared red–faced at me across the tables that separated us. He and his Berkeley team had just spent half the morning presenting their theory that a giant asteroid slammed into earth 65 million years ago killing most of earth’s life, including the dinosaurs (Alvarez et al., 1980). Their evidence was enrichment of the chemical, iridium, at the geological Cretaceous-Tertiary (K–T) boundary. Some extraterrestrial objects are enriched in iridium, and Alvarez claimed that the iridium was proof of impact. I did not agree. Four months earlier, at the January 1981 meeting of the American Association for the Advancement of Science (McLean, 1981a), I proposed that the Deccan Traps volcanism in India, one of the greatest episodes of mantle plume volcanism in earth history, had flooded earth's surface with carbon dioxide, perturbed the carbon cycle, triggered the K-T mass extinctions, and released the K-T iridium onto earth’s surface. My research indicated that the iridium was not proof of impact.

Luis Alvarez, who had big stakes riding on his theory, became angry with me. At the first coffee break, he "ushered" me into an isolated corner out of earshot of the others, and demanded to know if I intended to publicly oppose his asteroid impact theory. I told him that I had no choice but to continue with my research. My research was indicating that greenhouse climatic warming can trigger mass extinctions, and our civilization is today facing a possible greenhouse, so I had a moral obligation to continue with, and publish, my research. Alvarez then threatened me with the same fate that had befallen another scientist who had opposed him. “Let me warn you,” Alvarez said. “— — tried to oppose me, and when I finished with him, the scientific community pays no more attention to — —.” “You’ve been warned,” he concluded.

Alvarez had a long history of brutality toward others who stood in the way of his agendas, as witness the fate of J. Robert Oppenheimer, leader of our national atomic bomb project after World War II, whose career Alvarez helped to destroy. Alvarez's style of dealing with others is expressed in part by the following quote from Nuel Pharr Davis's Lawrence and Oppenheimer (1968, p. 314):

One of the leaders in the atomic establishment says that he was appalled by an intimation he caught in 1954 of the way anger and frustation had affected Alvarez' mind: "I remember a shocking conversation I had with Alvarez. It was before the Hearings (the Oppenheimer hearings). I want to make it clear that I am not giving his words but trying to reconstruct his reasoning. What he seemed to be telling me was 'Oppenheimer and I often have the same facts on a question and come to opposing decisions—he to one, I to another. Oppenheimer has high intelligence. He can't be analyzing and interpreting the facts wrong. I have high intelligence. I can't be wrong. So with Oppenheimer it must be insincerity, bad faith—perhaps treason?'

That afternoon, Walter 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.”

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. By 1984, some members of the impact community had reached into the Virginia Tech Department of Geological Sciences where I worked, and nearly destroyed my career, and health.

My departmental Chairperson, a petrologist, who had been highly supportive of my work, and who even wanted to write papers with me, became terrified on learning that a powerful Nobelist, Luis Alvarez, was publicly badmouthing me. He became even more distressed with me when Alvarez's politics, and those of two of Alvarez's main paleontologist supporters were slipped into the department. One, whose research in K-T science has been largely discounted, said that my work was "not going anywhere." The other, who has never written a scientific paper on the K-T extinctions that I am aware of, said that I had spent my career puttering in a "little square mile." Those cheap political shots, although incorrect, hurt me badly. I learned from a friend in the Dean's office that "someone could get fired" because of the K-T scientific debate. I was the only one on campus doing K-T science.

Academic freedom became a meaningless concept for me as my departmental Chairperson and his Assistant Chairperson tried to force me to stop my work on the K-T extinctions. The Chairperson, a petrologist, tried to divert me from K-T research by forcing me into writing up descriptive paleontological materials that had accumulated as part of my graduate research program when I desperately needed time to further develop the theoretical models I had created. I was attempting to articuate a Law of Nature which relates bioevolution and extinction to variations in earth's variable greenhouse, a topic of far greater significance than descriptions of fossils. The Assistant Chairperson, a geochemist, told me that my research should not be done at Virginia Tech, but at a think tank. He told me several times that I should relocate. His close colleague, also a geochemist, told me that Virginia Tech is "not designed to accomodate" my theoretical work. "It does reward your approach," he said. He also stated that I should relocate to "where my kind of work is appreciated." It was under those conditions of terrible harrassment that my health failed in 1984 while I was trying to hold up one side of one of the great scientific debates in history, that I had originated. To understand what happened to me, please read my Letter to Luis Alvarez, my Letter to David Raup, and my Letter to Stephen J. Gould.

In June 1980, the same month as publication of the Alvarez theory (Alvarez et al., 1980), 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. 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. No one has proven any dinosaur extinction theory to be correct.

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 shifted toward the Alvarez impact theory. It could hardly have been otherwise.

In the Big Sell, some popularizers of science—who have never published a scientific paper on the K-T extinctions—operated as experts to sell the Alvarez theory to the public. One even testified before Congress on the correctness of the Alvarez theory. 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.

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.

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.

In the historical analysis of the K-T debate that I am preparing, in which the actions of a few people tilted major attention to the Alvarez theory, my intent is to record historical aspects of the K-T debate as accurately, and scrupulously, as I am able. It is not my intent to demean or damage any individual, or institution. I want only to record for posterity some actions that might otherwise be lost to history. For Luis Alvarez, whose years-long personal attacks upon me nearly destroyed my career, I now feel no animosity. Please see my Letter of Condolence to Walter Alvarez that I wrote to him following the death of his father, Luis Alvarez.

Late breaking information: There are no fullerenes in the K-T boundary layer:

Fullerenes are a family of molecules composed of carbon atoms that are arranged into a cage-like structure with a hollow interior. The number of individual carbon atoms in individual molecules range from a few dozen to many hundreds. Such molecules that contain 60 carbon atoms (or 70) have a spheroidal shape resembling the geodesic domes created by Buckminister Fuller, and are known as buckministerfullerene, or bucky balls. Fullerenes can trap other types of atoms, such as helium and argon, within them. Some scientists have argued that the helium and argon ratios within some fullerenes are indicative of an extraterrestrial origin, and that such fullerenes found in K-T boundary sediments are evidence of impact event (Heymann et al., 1994).

However, new research has discounted the presence of fullerenes in K-T boundary sediments. R. Taylor and A. K. Abdul-Sada's reexamination of K-T boundary sediments using mass spectrometric analysis capable of detecting 0.001 parts per billion detected no traces of either C60 or C70. They published their findings in a paper titled "There are no fullerenes in the K-T boundary layer" (Taylor and Abdul-Sada, 2000).

In the mid-late 1970s, I was directing a Cretaceous and Tertiary marine microplankton graduate research program on the Atlantic Coastal Plain along the eastern margin of the United States. We often worked along the K-T boundary. My theoretical work on the K-T extinctions grew out of my research program. For the K-T extinctions, I began by examining them within the context of variations in the carbon cycle, one of earth's great cycles. By 1977, I identified what I believed was a major perturbation of the carbon cycle during the K-T, and proposed it in a paper in Science magazine titled "A Terminal Mesozoic 'Greenhouse': Lessons from the Past" (McLean, 1978).

The year 1979 was a good one for me. I coupled the Deccan Traps volcanism to the K-T carbon cycle perturbation and extinctions (McLean, 1981a, b, and later), and also isolated a physiological mechanism that links variations in earth's climate directly to vertebrate population dynamics, and thus to bioevolution and extinction. (Please see the text of A Climate Change Mammalian Population Collapse Mechanism [McLean, 1991] and Greenhouse Vertebrate Physiological Killing Mechanism). Linking variations in the carbon cycle to a physiological mechanism by which climate influences population dynamics provided what I believed was a universal mechanism that exerts control upon vertebrate bioevolution and extinctions through geological time. Basically, I am interested in all phenomena that can trigger perturbations of the carbon cycle sufficient to triggered changes in Earth's life, and that includes impact events. If a K-T boundary impact can be shown to be linked meaningfully to the extinctions, I will accept it, and go on with my work. (Please see Proposed Law of Nature Linking Impacts, Plume Volcanism, and Milankovitch Cycles to Terrestrial Vertebrate Mass Extinctions via Greenhouse-Embryo Death Coupling [McLean, 1994]).

In my K-T work, I have concentrated upon the Deccan Traps volcanism as a causative factor in the extinctions because it was one of the greatest episodes of mantle plume volcanism in Earth history, and the vast bulk of its lavas erupted right at K-T boundary time. The duration of its eruptions was coeval with major shifts in the carbon and oxygen stable isotope records, "Strangelove conditions" in the oceans, and the K-T bioevolutionary turnover. In addition, it occurred simultaneously with other phenomena such as marine transgression, reduced photosynthesis of terrestrial and marine floras, and reduced weathering rates that would all have contributed to producing a major trans-K-T perturbation of the carbon cycle (McLean, 1995).

I have long believed that my volcano-greenhouse model will serve as a mechanism to investigate the relationships between other major episodes of mantle plume volcanism, the carbon cycle, and extinctions. Following is a direct quote from Richard Kerr, staff writer at Science magazine: "Four other extinctions, both major and minor, have now been linked in time with huge basaltic eruptions like that of the Siberian Traps" (Science, 2000, v. 289, pp. 1666-1667).

The search for cause of a mass extinction event 65 million years distant in time has been a wonderful, but humbling, learning experience. The K-T world was more vast, and complex, than I could ever have imagined at the beginning of my work back in the middle 1970s. I never dreamed that I would have to integrate elements of up to two dozen branches of science to develop a working "picture" of the K-T transition world that I could operate within. Even more intimidating was the fact that in order to ever understand the K-T extinctions, one must consider them within the context of thermal evolution of the Earth, itself. One must reconstruct the physicochemical dynamics of the world before the time of an extinction event to examine how changes in that world might trigger mass extinctions. For the K-T transition world, this involves integrating elements of the Cretaceous and Tertiary fossil records (animal and plant, marine and terrestrial, microscopic and megascopic), biostratigraphy, physical stratigraphy, plate tectonics, the carbon cycle, stable isotopes, internal earthly processes that include mantle degassing, paleobiology, paleoecology, climatology, oceanography, biochemistry, the solar-earth-space energy flow system, and system dynamics, to name some. Knowledge of geological time-rock relationships is critical because they can create the illusions of instantaneous, catastrophic, extinctions where none occurred. Compounding the complexity, missing strata at the K-T boundary in most places has destroyed the data most critical to testing theories. Rebuilding the K-T transition world is like trying to assemble a gigantic jigsaw puzzle that has most of its pieces missing. And limitations confound us at every turn. For example, theories that evoke sudden, catastrophic, extinctions simply cannot be tested from the actual geobiological record because the K-T boundary rocks are usually missing at most localities.

For any progress I have made, I owe special debts of gratitude to a handful of people who gave me the inspiration and methodology to address the vastness and complexity of the K-T world. Albert Einstein provided a philosophy, and courage, to tackle the seemingly incomprehensible. Lord Kelvin's Second Law of Thermodynamics provided insights into my linking the thermal evolution of the Earth to evolution of Earth's biosphere. Jay Forrester provided system dynamics, methodology to find meaning in complexity. Ilya Prigogine's extension of the Second Law provided insights into how environmental fluctuations can invade systems, and grow into structure-breaking waves. And, of course, I owe thanks to many others, impactors and volcanists alike, whose thinking, and data, provided me a rich milieu within which to work.

In the broadest sense, the state of the biosphere at any time is a function of the rate of flow of energy from the sun to earth, and on to outer space. Variations in the carbon cycle influence the solar-earth-space (S-E-S) flow rates. Great volcanic events release greenhouse gases (water vapor and carbon dioxide) onto earth's surface, thus influencing the carbon cycle, and the S-E-S flow system. Thus, volcanism exerts control upon the state of earth's biosphere in ways to influence bioevolution and extinction. So vast was the Deccan Traps volcanism that it would have flooded earth's surficial systems with carbon dioxide faster than they could have absorbed it, creating fluctuations that would have grown into structure-breaking waves that would have invaded and destabilized them, forcing life to change, or become extinct. Some forms of life, such as the dinosaurs—in the strict sense—could not do so, and became extinct. To examine how earth's systems are interconnected such that changes in one might affect others see the Holistic Earth Causal Loop Diagram.

NOTE: The Deccan Traps research is but a special theory within the general theory that variations in the carbon cycle exert control upon bioevolution and extinction.

		Sixty-five million years ago, right at K-T boundary time, and coinciding with major shifts in the oxygen and carbon stable isotope records, and the K-T extinctions, the vast bulk of the Deccan Traps lavas erupted onto earth's surface (Basu et al., 1993). One of the greatest episodes of volcanism in earth history, it flooded over a million square miles of India and surrounding areas with layer after layer of basaltic lava flows, one over the other, forming a vast lava pile. Today, after 65 million years of erosion, the Deccan Traps lava pile is still about one and one-half miles thick in western India, near Bombay. For details of the Deccan Traps mantle plume volcanism, please see the Deccan Traps Mantle Plume Volcanism and Brazos River, Texas, Isotope Record.

In the early 1980s, the K-T boundary iridium enrichment provided the sole basis for the Alvarez impact theory. At the January 1981 national meeting of the American Association for the Advancement of Science meeting held in Toronto, Canada, I proposed that the Deccan Traps mantle plume volcanism likely released the K-T boundary iridium onto earth's surface, and did so later at the May 1981 Ottawa K-TEC II meeting, and at the October 1981 Snowbird I Conference (See References). Earth's core is rich in iridium and the Deccan Traps mantle plume, originating at earth's core-mantle interface, likely served as a conduit to transport iridium from the core to earth's surface. In fact, the hotspot volcano that produced the Deccan Traps (Piton de la Fournaise on Reunion) is still releasing iridium today (Toutain and Meyer, 1989).

	Earth is zoned into great spheres. At earth's center is the partially molten metallic core. Next outward are the mantle, crust, hydrosphere, atmosphere, and biosphere. Via the 2nd Law of Thermodynamics, earth loses its internal heat to outer space. This heat flow determines the direction and rate of evolution of the earth. It causes convection in the mantle, causing the continents to drift about on earth's surface, and carries materials, and gases such as water vapor and carbon dioxide, to earth's surface via volcanos, fumaroles, and hot springs. As the earth loses its internal heat to space, the great spheres must evolve along with it. Thus, thermal evolution of the earth, by forcing changes of the biosphere, is a driving source of bioevolution and extinction.

In earth's early history while it was forming as a protoplanet, water and carbon dioxide were trapped inside it. Later, when the entire earth melted, water vapor and carbon dioxide were sweated out of earth's interior to the surface. This process is called mantle degassing. Mantle degassing continues today as volcanos, fumaroles, and hot springs release these gases into earth's atmosphere.

Water vapor and carbon dioxide in the atmosphere are called greenhouse gases because they trap heat from the sun, warming earth's surface. These gases are always present in the atmosphere so earth is a perpetual greenhouse planet. Without them, earth's surface would be frozen solid. As it is, earth's surface is about 30 degrees K warmer than it would be without them, allowing earth to support life. However, the greenhouse effect varies through time and, as it changes, earth's life must evolve along with it or become extinct.

Over long geological intervals, a steady state exists between release of greenhouse gases upon earth's surface and their uptake by surficial systems. At those times, relative ecological stability prevails on earth's surface. However, vast episodes of mantle plume volcanism, such as the Deccan Traps, releases vast amounts of CO2 onto earth's surface faster than it can be taken up by surficial sinks, disrupting the steady state to which earth's surficial systems are adapted, triggering a perturbation of the carbon cycle, ecological instability, and mass extinctions (McLean, 1985a, b, c).

Study of the Deccan Traps model promises to shed new light on the role of earth's thermal evolution upon the evolution of life. Most interestingly, the great Permian-Triassic mass extinction of 250 million years ago, the greatest mass extinction in earth history, coincided with the Siberian Traps volcanism in Siberia, one of the greatest episodes of flood basalt volcanism in earth history (Renne et al., 1995). The K-T and Permo-Triassic marine extinctions show striking parallels between environmental CO2 buildup and extinctions.

		Major carbon cycle perturbations affect nearly every aspect of earth's surficial systems, and in often drastic ways. As carbon dioxide builds up in the atmosphere, causing greenhouse climatic warming, climate zones shift causing tropical conditions to migrate over temperate zones. These shifts in climate zones trigger great ecological instability, migrations of animal and plant populations, expand the range of tropical diseases to plague temperate-adapted organisms, and cause them to experience elevated body temperatures, a condition known as hyperthermia, beyond their experiences. In the oceans, warming, and acidification of the upper waters as atmospheric carbon dioxide diffuses into them, can kill life on a massive scale. For example, warming of Pacific Ocean waters during modern El Niño events devastate marine life. And, as prey species migrate to cooler regions, animals dependent upon them for food might starve. Based on my studies of the impact of greenhouse warming upon life, I believe that a major perturbations of the carbon cycle can trigger transitions from order into chaos, and are the most dangerous phenomenon that life can experience.