Her mother was the oldest of a dozen, her father the youngest of 18. She was the sixth of 12, and her mother’s confidante. She was born in Liechtenstein, just weeks before the close of the Second World War. The family soon moved just a few miles away, across the border into Switzerland. There still were military camps nearby, and the kids would go to the soldiers to ask for leftover food.
Their farm in Switzerland went on the auction block every six months or so, but there were no buyers because no one wanted to put a family with a dozen kids on the street. Eventually the government stepped in and ran the farm, giving the family an allowance.
Gerta learned to find snails, which she could sell for a few dollars a kilo.
“Even when I was 4 years old I would go all day long with two buckets to look for escargot. I would walk as much as five to 10 miles a day, all over Liechtenstein and Switzerland, and collect these white, big snails,” she says. “I loved the mountains. I would go hiking in the mountains, the forest. I didn’t pay much attention to rocks. I mostly paid attention to flowers.”
But she wanted more.
“I really longed to see the world. I was a voracious reader. I would see planes occasionally going overhead, and I would dream of what it would be like to see other places.”
In another black-and-white photo on her office wall, she’s standing by a watering trough, wearing a new, home-sewn dress. “My mother made it,” she says, “but she was a very bad seamstress. It was so tight that that was the only day I could wear it, because it tore apart. But I was very proud of that dress, the few hours it lasted.”
At 12, she decided she wanted to be a doctor. She remembers being told that she had to be realistic: “You can be a housemaid, a salesgirl, or you can be a dressmaker.”
At 14, she became an apprentice to a dressmaker. She gradually grew depressed. She started working as a waitress, saved some money, and finally, at the age of 18, hit the road. She went to England to study English. She visited North Africa, the Middle East, Eastern Europe, and Greece, and caught hepatitis along the way. She returned to Switzerland to recuperate, and then, at 20, emigrated to Australia.
One day she and a friend were returning from a trip to the beach near Sydney when they noticed that there were no other cars on the road. A man in a trench coat was running, shooting a rifle. A movie, they thought — someone’s filming a movie. Except there were no cameras. The man — a bank robber — came up to their car and demanded that they get out; then he shot Keller in the upper arm, and the bullet went through both lungs. She collapsed and her friend pulled her out of the car.
“I looked up at the sky. The whole sky seemed like a canvas. My life from my youngest days all went by. I thought, so, that’s it, this is what it’s like when you die.”
At the hospital, a priest insisted that she make a final confession.
“I have nothing to confess,” she said. She thinks her anger in that moment — her contrarian rage — saved her life.
That was 1967. She was not quite 23 years old. When she recovered, she flew with her boyfriend, Tim Callahan, to San Francisco and began to reinvent herself as a student. The counterculture was in full flower. She married Callahan — the union would last four years — and started taking college classes, first at City College, then graduating from San Francisco State. She was obviously bright, and determined, and she won over the geologists at Stanford, who accepted her as a Ph.D. candidate in 1973.
Sometimes, though, she got on people’s nerves. The field was dominated by men, some of whom were not accustomed to dealing with a strong-willed woman.
“She’s very stubborn, independent, not afraid to express her opinion,” says John Barron of the U.S. Geological Survey, who knew her in the 1970s. “She’s just so much different from what women were at that time.”
He adds: “She once told me that ‘Gerta’ was the spear wielder in German. She has certainly lived up to her name.”
Geology is a field that gets shaken up regularly. When Alfred Wegener proposed his theory of continental drift early in the 20th century, few people took him seriously. There simply was no way that something as huge as a continent could plow through the crust of the Earth, it seemed. Now, in revised form, continental drift is the orthodoxy; it’s impossible to discuss the history of the Earth without referring to plate tectonics — a theory developed to a significant extent at Princeton in the 1960s under the leadership of geology department chairman Harry Hess *32.
The Alvarez theory, likewise, redeemed the musty, pre-scientific notion that the Earth’s history has been shaped by catastrophic events. The field of geology in 1980 long had been dominated by the doctrine known as uniformitarianism. First promulgated by James Hutton and Charles Lyell in the 18th and 19th centuries, this was the belief that the planet had changed very gradually over long periods of time, an idea boosted by the discovery of Darwinian natural selection.
This is a field, it seems, where there is rarely anything that might be called a settled fact. It’s innately interpretive. Geologists work with broken, eroded, baked, compressed, and very old material. Rocks don’t speak. There always will be arguments about what the geological record is trying to say. “Geological data are messy, by necessity. There is always a devil in paradise,” Jan Smit, one of the originators of the K/T impact hypothesis, has written.
So it was that, as the Alvarezes’ impact theory was being developed, there remained skeptics such as Keller. Even after the discovery of the Crater of Doom, hailed as a smoking gun for the impact, a number of scientists challenged the orthodoxy. Two of the most prominent were professors at Dartmouth, Charles Officer and Charles Drake, both of whom preferred the Deccan Traps as the killing mechanism.
Keller was a bit late to get into the debate (“I didn’t want to jump on a bandwagon like everyone else,” she says). It was only in the mid-1980s that she dove in, first at a conference at Snowbird, Utah, where, as she recalls, she was such an unknown that she was introduced as “George.” She presented slides, based on her study of the K/T boundary, indicating that the extinction didn’t happen in one instant but rather over a broader period of time. A line quickly formed as one scientist after another wanted to take issue with her argument.
“That was considered incredibly heretical and I was attacked unbelievably,” she says. “It was almost pandemonium at the end.”
She recalls a colleague coming up to her at lunchtime, saying, “Gerta, you should know when you should shut up. You have to be more diplomatic.” Her response: “I can’t shut up if it’s so untrue what they’re saying.”
Keller has suggested that the mass extinction came from a one-two punch: The volcanic eruptions changed the climate, and weakened species then were finished off by a meteorite impact — though not the one at Chicxulub. She co-authored a study reporting signs of a meteorite strike in India from the time of the mass extinction. Such an impact could explain the iridium found at the K/T boundary, she says. Or perhaps the iridium came from volcanism bringing material from deep within the Earth. “I can’t say one way or another,” she says. But she’s convinced that the Chicxulub impact didn’t cause the K/T iridium anomaly or the mass extinction.