Why We Should Pay Attention to Gerta Keller's Battle with the Alvarez Impact Theory
Why We Should Pay Attention to Gerta Keller's Battle with the Alvarez Impact Theory
By Phil Wilson
I am hiking along the Metacomet Ridge in Greenfield, Massachusetts - a rather steep basaltic structure, modestly less than five hundred feet high and topped by a stately brick tower constructed in honor of transcendentalist poet, Frederick Goddard Tuckerman.
Today, in mid spring, a cloudless sky and blissfully warm breezes carry the odor of blossoms and the fragrance of pine. A solitary hawk circles lazily above. The woods boast the typical array of New England trees - hemlock, birch, oak, maple, locust, fir and spruce. Squirrels chatter and birds of all sorts can be seen soaring below the ridge in shifting, collective shapes - crows, finches, sparrows and even vultures. Movement, vagueness, the shaping and reshaping of wind-blown shadows paints a path streaked with green, blue and brown - the colors of life. Immersed in the spell of nature, one does not easily reflect on the historical role of the Metacomet Ridge, part of the Central Atlantic Magmatic Province (CAMP). Nor does it at all seem as though I am hiking both within an unfolding mass extinction event while contemplating the remnants of one of the all-time lethal murder weapons of the ancient past.
The CAMP is the likely smoking gun for one of the five great mass extinctions of geological history - the end Triassic. Some two hundred million years ago as the continent of Pangea broke apart magma flowed from a series of rifts, and parts of a "large igneous province (LIP)," now remain in Africa, South America and North America. I had hiked these trails for decades before a community college geology course imposed context upon my private affair with nature. For almost all of human history plate tectonics eluded science. Now, in my short lifespan, the history of the planet has opened up like an enormous flower.
We now understand the historic role of volcanic greenhouse agents - the serial killer of deep time.
According to Princeton geologist, Gerta Keller, all five of the earth’s great mass extinctions originated with volcanism. The last one, Keller asserts, can be traced and dated precisely to remnants of an LIP in India - the Deccan Traps. There is a general consensus about the lethal legacy of the basalt flow under my feet. The end Permian, the lord of all earthly apocalypses, allegedly originated in the volcanism of the Siberian Traps some 252 - 251 million years ago, and few scientists take issue with that conclusion. But the K-Pg extinction has been popularly traced to a wayward meteor some 66 million years ago, and Keller's fidelity to mother-nature’s volcanic habits has come to be regarded as an act of paleontological heresy.
Paleontology has historically attracted colorful, contentious, irascible pioneers - men, for the most part - craving excitement and eager to engage in faraway expeditions to places like the Gobi Desert in Mongolia, or the badlands of Montana. Ancient fossils are most accessible in barren areas with exposed sedimentary rocks. In the 1920’s the American Museum of Natural History sent a group of armed fossil hunters to the Gobi under the leadership of Roy Chapman Andrews. Chapman Andrews began his professional scientific career as a museum janitor. He kept a gun in his belt to protect himself from “bandits.” Chapman Andrews may have been the inspiration for Indiana Jones, but one may also imagine him as a colonial plunderer pilfering Chinese fossils on behalf of American science during a time of US imperial expansion. He saw no irony in his use of the word bandit. The first US expedition to the Gobi desert took place during the administration of Herbert Hoover – a time of unprecedented economic growth, the roaring twenties. Paleontology has long worn the aggressive cloak of patriarchy.
One of the most famous scientific feuds of all time - designated as the "bone wars"- pitted two 18th century fossil hunters, Othniel Charles Marsh and Edward Drinker Cope, in a manic race to find and identify the most new dinosaur species. There were no theoretical issues girding the battle between these two - naked ego sustained this feud.
The battle between Gerta Keller and the late Nobel Prize winning physicist, Luis Alvarez, and his son, paleontologist Walter Alvarez, may have involved narcissistic undercurrents, but a substantive issue keeps the feud alive 36 years after Luis Alvarez’s death. Since the days of Marsh and Cope the mystery of dinosaur extinction has tormented much of humanity.
Keller, a woman in a field famous for larger than life men, is one of the most unlikely scientific protagonists ever. Born in 1945, she grew up in a poor family on a farm situated in Liechtenstein - the 6th of 12 children. In her culture, girls were expected to leave school in their early teens and work at menial jobs in either clothing manufacturing or farming. Keller worked in a dress factory throughout her teens for 25 cents an hour until she attempted to take her own life with an overdose of sleeping pills. According to journalist, Bianca Bosker, Keller declined to delve into the reasons for her suicide beyond a rather generic nod to sexual harassment and poverty. Nor did Keller elaborate much to Bosker about the internal complexity that set her off on a global odyssey. I have watched a number of interviews with Keller, and she tells a beguiling, fascinating tale that somehow never ventures into her internal spaces. We are left with a skeletal plot separating Keller’s childhood in a remote, intolerant culture, and her Phoenix-like emergence as a renowned scholar. In between, we learn that she wandered across the face of the earth goaded by a vague death wish.
These seemingly aimless, frantic international treks across Europe, the Middle East, North Africa, Australia and Asia featured a number of near death experiences and one might simply adopt the facile interpretation that Keller had melded her suicidal propensities to a rather inchoate curiosity. Keller’s minimalist confessional style demands that we fill in the blank spaces as best that we can. All along, one daringly speculates, Gerta Keller was searching for her great white whale - ultimately she found it in Luis Alvarez. In the end, Keller, who had nearly been destroyed by the most toxic and extreme version of parochial patriarchy, honed in on her masculine target.
We should not diminish the Alvarez/Keller confrontation - reduce it to a mere example of oversized egos vying for academic acclaim. No, this is a shadow drama of the subconscious, a morality play, an essential reckoning, an allegory defining the uncertainty of our times. Are we to see the saurian demise as a biblical apocalypse sent from the heavens (masculine retribution) or do we see the dinosaurs as falling via the slow, steady rhythms of mother earth? The feud between Alvarez and Keller is, among other things, a story about gender masquerading as a scientific disagreement.
In her early twenties, Keller almost died after being shot outside a bank in Sydney, Australia by an escaping robber. A priest attempted to give Keller the last rites, but his insistence on her confessing her sins, she told Bosker, made her so angry that she refused to die - yet another showdown with the patriarchy. The story of Keller’s life is a feature film begging to be made, full of action, for sure, but also with the space and silence of European surrealism. Most of Keller’s story remains untold. What happened to her family in Liechtenstein? One interviewer coaxed Keller into disclosing that she has been married for decades and loves to garden, but even that was like pulling teeth.
She recovered from the gunshot that collapsed one of her lungs and travelled throughout Asia. In her middle twenties, with only a 7th grade education, she arrived in San Francisco and somehow hatched a plan to go back to school. Keller made up a tale about her high school transcripts having been lost in a fire - the school authorities accepted her story and she began studies in a local community college before transferring to San Francisco State College. There, an advisor recommended that she focus on geology. If you like to travel, there are rocks everywhere and someone is always willing to fund your research, he told her.
It is difficult to believe that a scientist as important as Keller simply fell into her niche by a series of serendipitous events. I prefer to imagine Keller’s story as having the purpose, economy and preordained motion of fiction. Every twist and turn leads inevitably to Luis Alvarez.
Keller attended Stanford and graduated with a doctorate in geology and paleontology in 1978 - she was 33 years old, a reasonable age to attain such an honor, but an almost inconceivable achievement for someone who had spent a full decade working in starvation wage factories and travelling about the world with no viable plan. Then there is the matter of class and social context. World class scholars do not generally emerge from rural poverty. No one in her family had ever been to college. But the story gets even stranger – Keller did not become a paleontologist content, like Chapman Andrews, Marsh and Cope, to crawl about searching for old bones. Rather, she became one of the world’s foremost authorities on fossilized foraminifera – microscopic protists that exist abundantly in the fossil record. These according to Keller, act as a proxy for the haphazard and woefully incomplete fossil record of vertebrates. She argues that mass extinctions leave a vivid imprint in the fossilized remains of microscopic life. She developed exactly the sort of rarified, eclectic expertise that seems eerily designed to place her at the center of mass extinction controversy. You could not make this up – which is what we always say about true stories that resemble fiction.
In 1980 world renowned physicist, Luis Alvarez, along with his son, the paleontologist, Walter, discovered the iridium layer at the K-Pg (Cretaceous/Paleogene) boundary near Gubbio, Italy. This would soon lead to a new theory of dinosaur extinction. The dinosaurs succumbed to the ultimate act of cosmic violence. The magnificently adapted, dominant terrestrial animals for 135 million years were deleted instantly from the fossil record according to the Alvarez duo. All that they needed was an impact crater, and that turned up in 1991 when geologists working for oil prospectors discovered an enormous depression in Mexico’s Yucatan Peninsula. The parts fit together almost perfectly and, almost instantly the academic community and the public accepted the killer meteor theory as established truth. The issue was closed.
If one sees Gerta Keller as an improbable protagonist in this bizarre narrative, who emerged out of nowhere, Alvarez is an equally unlikely character in our story. His biggest claim to fame involved his role in developing the nuclear weapons for the Manhattan Project that had been dropped on Hiroshima and Nagasaki. Alvarez even flew along as an observer in a plane called The Great Artiste that accompanied the Enola Gay in its mission to obliterate Hiroshima. He had seen Armageddon as intimately as anyone might – not simply seen it, but created it. With the discovery of the Italian iridium layer and the Chicxulub crater, Alvarez understood that the non-avian dinosaurs had their own Hiroshima. Indeed, the Chicxulub meteor is invariable quantified in Hiroshima’s terms – the meteor struck down with the force of 100 million Hiroshima bombs we are told.
Keller has alleged that Luis Alvarez used his position of authority to intimidate those who disagreed with him:
"Luis Alvarez’s personal attacks went beyond paleontologists to anyone that disagreed with the impact hypothesis and especially those who offered Deccan volcanism as the alternative killing mechanism. Special invective was also reserved for geologists Charles B. Officer and Charles L. Drake and physicist Robert Jastrow at Dartmouth College who advocated intense volcanism and sea-level changes as likely cause for the Cretaceous-Tertiary boundary (KTB) mass extinction."
Keller has been careful not to dwell on sexism as an impediment to her career, but to, rather, let her writing and research speak for itself. But one of her colleagues, Vincent Courtilott, told Bianca Bosker:
"She is a forceful woman and she is a courageous woman in a world where, I don’t have to tell you, for someone to rise to the top of geology as a female is much harder than for a male,”
As a person who once travelled aimlessly about the globe in an effort, one might assume, to evade the trauma, depression and emptiness that life in a sexist culture inflicts, Keller has become obsessively focused, perhaps monomaniacal. She told Bianca Bosker that Alvarez could not intimidate her as he did others:
"The more people attack me, the more I want to find out what’s the real story behind it.”
She has relentlessly attended to the issue of the K-Pg boundary, travelling to hundreds of sites to take data and publishing some 250 peer reviewed papers. She has made a number of assertions about the 5th extinction including:
1) The fossil record of foraminifera shows a gradual, rather than sudden decline up to the K/Pg boundary. This suggests that the extinction occurred via protracted climate and chemical changes and not in a sudden, extraterrestrial driven apocalypse.
2) Examination of fossilized foraminifera colonies in the post impact Chicxulub crater area show that microscopic life continued to thrive in the immediate aftermath of the meteor strike. This, Keller states, proves that the lethality of the meteor has been a matter of partisan hyperbole that the fossil record fails to support. Keller also asserts that no substantial climate change can be confirmed in the post Chicxulub geological record.
3) The glassy spherules, shocked quartz granules and tektites associated with the impact event are separated from the iridium layer by as much as eight feet of sediments. This suggests that the iridium, rather than being of extraterrestrial origin, might have resulted from later volcanism (which is also, according to Keller, rich in iridium). Proponents of the Alvarez theory argue that the sediments separating the two layers reflect the accumulated residue of a massive tsunami, but Keller has examined the sediments for foraminifera and determined that the fossilized microbes that she discovered in the dividing layers could only have flourished in gradually deposited layers.
4) Keller’s radiometric dating of Basaltic flows in the Deccan Traps regions suggests that the maximum intensity of lava deposition occurred in the 40,000 year interval immediately corresponding with expected reductions of foraminifera. This interval concluded, according to Keller, with the K/Pg extinction. Paroxysmal Deccan eruptions have been dated to the 25Ky period leading up to the extinction
5) Keller dates the Chicxulub impact as occurring at least 100,000 years prior to the K/Pg extinction event.
Keller often tells a story from her school days about organizing resistance against a policy requiring girls to wear dresses. She explains that she had to walk several miles in deep snow during winter. The authorities relented so long as she changed from pants to a skirt upon arrival. She refused to do so and the authorities simply threw up their hands. Keller had been battling against patriarchy since childhood. But Luis Alvarez was no ordinary patriarchal symbol, but a man credited with helping to design the most terrible weapon of war in human history, and then taking that weapon and employing it as metaphor for mass extinction. The dinosaurs had died in a nuclear strike, albeit from not one, but a hundred million Hiroshima bombs. What is more, Alvarez was well known as an academic bully – an opinion embraced by several of Keller’s colleagues.
Alvarez almost bullied the impact theory into a position of unquestioned hegemony. Eventually it became unsafe to advocate for the Deccan Volcanism theory of mass extinction. Scientists were wary of Alvarez’s attacks and fearful of losing opportunities for tenure. Only Keller remained as a lone voice against the “impactors.” Alvarez died in 1988 but venom between the hegemonic impactor camp and the now growing contingency of geologists rallying to the Deccan Traps volcanism theory still continues.
Why does it matter how the dinosaurs disappeared? Corporations and governments are quite possibly destroying the planet in a K-Pg reprise and they employ neither meteors nor volcanoes. But Keller has placed our methods of self-annihilation alongside the behaviors of tectonic movement. I am quoting Bianca Bosker’s 2018 Atlantic piece:
“Keller fears that we are filling our environment with the same ingredients—sulfur, carbon dioxide, mercury, and more—that killed the dinosaurs and that, left unchecked, will catalyze another mass extinction, this one of our own devising. “You just replace Deccan volcanism’s effect with today’s fossil-fuel burning,” she told me. “It’s exactly the same.”
There are places on the steep Metacomet ridge where one can safely descend the basalt columns and balance on heaps of eroded slag. From these vantage points one can intimately gaze into the face of deep time. The lava did not flow in a single cataclysm – it poured out across thousands of years and the empty magma chambers slept and refilled. Lakes, swamps and ponds meanwhile formed on top of the cooled lava and deposited layers of sediment. I am pulling out a thin slice of shale encased between massive basaltic structures above and below. Volcanism and sedimentary deposition took turns across hundreds of thousands of years.
If Keller is right then mass extinction on earth doggedly adheres to a recognizable template, and our own crisis – for all its volitional idiosyncrasies – follows the same plot line. It has even been proposed that the end Permian extinction involved the ignition of coal fields as Siberian Traps lava flowed across vast carbon deposits. India today is the second leading global coal producer and those Deccan Traps flows that Keller describes as traversing the entire Indian Continent run right smack through the richest coal mining districts. Might that be the common method, the nexus between humankind and run away volcanism – the burning of coal?
I have quoted Keller as saying that the Deccan Traps eruptions and our current burning of fossil fuels are “exactly the same,” but Keller, in other interviews has stated that our rate of warming is much faster and that the end result might be even worse than any volcanically precipitated extinction. Keller’s observations fit into the increasingly dark and ominous warnings by scientists like Gavin Schmidt who states that we may be in “uncharted territories.” or James Hansen’s statement that we have reached a point where geoengineering is now necessary.
At the heart of the debate between Keller and her supporters and those arguing on behalf of Alvarez’s theory is the matter of time. Do extinctions transpire across eons, or do they come on in a fit of cosmic rage – a “bad weekend?” And how slow is slow? Keller has proposed that volcanic emissions perform lethal deeds across the eons, but also speed forward in particularly condensed pulses of volcanic escalation. The K-Pg extinction climaxed with a mere 25Ky of paroxysmal eruptions she argues.
Time is the big question for us. How much time do we have to reach net zero, to employ new strategies of economic slowdown, to build a climate movement large and passionate enough to battle against those contributing to the growing concentrations of atmospheric greenhouse gasses? In the past four years atmospheric carbon has risen by 10 parts per million. That rate would double our atmospheric carbon in less than 200 years. Exxon is the Deccan Traps on steroids.
NASA has already responded to the fears of a meteor strike by launching the Dart mission to redirect an asteroid, but a speeding rock from the outer solar system is not our most fundamental threat – slowness is. The earth is heating by human designs, just not fast enough to mobilize action. That is why I prefer Keller to Alvarez, all other issues aside, she clarifies that what is now happening to the planet has happened before - and the same ending has repeated itself five times.