The Toba Catastrophe Theory

Lake Toba (photo by Andrey Samsonov)

Lake Toba (photo by Andrey Samsonov)

Werner Herzog’s quite enjoyable, and typically discursive, recent documentary Into the Volcano featured a short vignette on a specific volcanic eruption, and a theory associated with it, that I hadn’t encountered before.

Around 74,000 years ago, one of the Earth’s largest-ever volcanic eruptions, the Toba super-eruption, happened at what is now Lake Toba, in the northern part of the Indonesian island of Sumatra. According to the Toba Catastrophe Theory, this eruption caused a planet-wide volcanic winter that lasted six years or more, as well as global cooling that extended over a thousand years. Because of this, according to a related theory, the ancestors of modern humans nearly died out, or at the very least were severely challenged.

This super-eruption, sometimes called the “Youngest Toba Tuff” or YTT eruption, has been called “the largest known volcanic eruption in the history of the human species,” and is generally believed to have been the largest of the last 2.5 million years. Its estimated volcanic explosivity index was 8, the maximum possible. By way of comparison, the Toba super-eruption was about 100 times larger than the largest recent eruption, the one in 1815 at Mount Tambora in Indonesia, which resulted in 1816’s “Year Without a Summer” in the Northern Hemisphere. Current research says that Toba expelled an amazing 700 cubic miles of magma – one article put that number in context by saying that this mass is roughly equivalent to 19 million Empire State Buildings. The famous Krakatoa eruption of 1883 released only about 3 cubic miles of magma.

All life in the immediate area of the Toba super-eruption must have been destroyed. At least six inches, and perhaps even several feet, of ash were likely deposited over the entirety of South Asia, including the Indian Ocean and South China Sea. The volcano itself collapsed to form a huge caldera now home to Lake Toba, the fifteenth-deepest lake, and largest volcanic lake, in the world.

Michael Rampino and Stephen Self have argued that the Toba super-eruption caused a “brief, dramatic cooling or ‘volcanic winter.’” Temperatures around the world would have dropped, they suggest, by several degrees, and contributed to the beginning of the last glacial period, the Würm glaciation, which had probably already begun but was helped along by Toba.

This eruption might also have prompted what has been called a “population bottleneck” in the course of human evolution. Somewhere between 50,000 and 100,000 years ago, so the argument goes, the worldwide human population decreased sharply, perhaps as low as 3,000. There is some genetic evidence that all humans alive today are descended from just 1,000 to 10,000 breeding couples that lived around 70,000 years ago, and that the bulk of genetic differences between modern human populations dates from that time, rather than a more gradual process spread out over hundreds of thousands of years.

According to the “population bottleneck” theory, the Toba eruption and the resulting volcanic winter led to a global ecological crisis that could have destroyed most of the food sources available to the human population, thereby resulting in that much smaller population. Some evidence can be marshaled to support this idea. Mitochondrial DNA have shown that the major human migration from Africa happened between 60,000 and 70,000 years ago, which fits with the Toba timeline. There is also some evidence of genetic bottlenecks in other species from certain regions at that time, including chimpanzees, orangutans, tigers, and cheetahs.

On the other hand, a seven-year project led by Oxford University along with several Indian institutions found that many forms of life then existing in India survived the Toba super-eruption. This included human populations that seem to have been there at that time, whose stone tool assemblage, very similar to that of the human populations in East Africa, remained consistent before and after the super-eruption. (This is controversial, however, because there is argument about exactly when modern humans first arrived in India.) Also, in East Africa, where most or all humans lived at that point, there was apparently no volcanic winter, or even much of a change in climate. Farther afield, in Europe, Neanderthals certainly survived whatever global impact the Toba eruption had. However, it has been suggested that the eruption might have forced humans to adapt to a new environment, which helped them ultimately to replace the Neanderthals.

It is clear that as a result of the Toba super-eruption, some areas were totally devastated. Others, however, experienced minor changes and recovered very quickly. Not many people embrace the Toba Catastrophe Theory anymore, it would seem. Nor is it generally thought that there is a connection between the super-eruption and major changes in the human population that existed at that time. But the evidence either way isn’t extensive, and the theories are certainly interesting.

Sunday Salon 11-6-16

Sunday Salon badge squareTime and Place: 8:00 Sunday morning, at my main computer at home.

Viewing: I gave in to the overwhelming temptation and signed up yesterday for FilmStruck, the new streaming service from Turner Classic Movies and the Criterion Collection. An initial impression of the offerings, which in short look really good, will be following here in a few days. Last night, for my inaugural, I chose relatively at random two films I hadn’t previously seen. Beyond a Reasonable Doubt, the last American film directed by Fritz Lang before he returned to Germany, was not bad but didn’t overwhelm. Madhumati, a 1958 black-and-white Bollywood film directed by Bimal Roy, was fabulous in every way. It is one of nine Bollywood films currently featured at FilmStruck, and I feel a Bollywood binge coming on.

Listening: As I wrote last week, my major project for the next couple of weeks is the writing of program notes for the 2016 Nevada Chamber Music Festival presented by the Reno Chamber Orchestra. My music listening will likely be confined to pieces played at the Festival, which isn’t such a bad thing.

Reading: Having finished Elena Ferrante’s My Brilliant Friend, I have just started a translation-retelling by Linda Egenes and Kumuda Reddy of The Ramayana, in anticipation of the exhibition on the epic at San Francisco’s Asian Art Museum that I will soon be seeing. Thupten Jinpa’s A Fearless Heart and Julia Cameron’s The Right to Write are ongoing.

Blogging: It was, sadly, another slow week on the blogging front…

* My review of My Brilliant Friend by Elena Ferrante
* A couple of election-related cartoons from The New Yorker
* A quote on “permanent childhood” from Constantin Brancusi

Pondering: (1) When I left home this morning at 6:15 to go to the gym, the clouds were such that a golden glow suffused everything as the sun was rising, even setting the distant mountains off in relief in a vivid, uncharacteristic way. The quality of light was remarkable. By the time I left the gym at 8:00, a dull gray had set in – attractive in its own gloomy way, I suppose, but I think it was worth getting up early on a Sunday for the golden glow. (2) The life I lead now is such that if I chose to disappear tomorrow, no one would know that I was gone, at least not for several weeks. The freedom that comes with that has some appeal, I have to admit. But it would still be nice if someone noticed my absence. (3) If I never again see a political commercial, I could live with the loss.

Anticipating: In a few hours I will be heading to the Nevada Museum of Art to check out the latest exhibitions. Two weeks or so away is a trip to San Francisco to check out the museum offerings there. Some marvelous visual art is in store for me.

Gratuitous Bollywood Songs: Someone was kind enough to put some of the songs from Madhumati, the Bollywood film I watched last night, on YouTube. So I thought I would share two of them, highly enjoyable even without translations of the lyrics. The first, “Zulmi Sang Aankh Ladi,” comes early in the film, just before our hero and heroine speak to one another for the first time. The subject of the second, “Chadh Gayo Papi Bichua,” is a scorpion bite. The lead singer and dancer in both songs, Vyjayanthimala, was one of the biggest Bollywood stars in the 1950s and 1960s (and later served in India’s Parliament). She is among the highlights of Madhumati, for reasons that become clear below.

Elena Ferrante: My Brilliant Friend

ferrante-my-brilliant-friend-coverMy Brilliant Friend
Elena Ferrante
Translated by Ann Goldstein
(2012, Europa Editions, 331 pages)

Elena Ferrante’s four Neapolitan Novels – My Brilliant Friend, The Story of a New Name, Those Who Leave and Those Who Stay, and The Story of the Lost Child – have become something of a sensation. After all the hubbub regarding the apparent exposing by Claudio Gatti of the formerly pseudonymous Ferrante’s actual identity – good commentaries are available here and here – I thought it was finally time to find out for myself what makes Ferrante’s books so appealing for people.

The series as a whole examines the friendship of Elena, the story’s narrator, and Lila, her “brilliant friend,” starting in 1950s Naples and extending over the next fifty years. As the book’s subtitle explains, the first novel – beautifully translated by Ann Goldstein, who in addition to her much-acclaimed translating work is head of the Copy Department at The New Yorker – begins with their “Childhood, Adolescence.” Both born in 1944, Elena and Lila meet in first grade. Elena, the narrator, writes that their life was in large part defined by their fears – “words that killed: croup, tetanus, typhus gas, war, lathe, rubble, work, bombardment, bomb, tuberculosis, infection.” The poverty and violence surrounding the girls as they grow up are, for them, normal, matter-of-fact: “Men returned home embittered by their losses, by alcohol, by debts, by deadlines, by beatings, and at the first inopportune word they beat their families, a chain of wrongs that generated wrongs.”

Each of the girls comes from humble backgrounds. Lila’s father is a shoemaker, and Elena’s a porter at city hall. Lena is blond, tends toward being overweight, and is relatively passive. Lila, on the other hand, is dark in color, thin, and energetic, and occasionally suffers from episodes of what she calls “dissolving outlines,” in which people, sounds, the entire world, seem strange and unfamiliar, even monstrous, as though some awful part of their true natures was being revealed.

From the first, Elena regards Lila with a certain amount of awe for her extreme, apparently effortless, intelligence. Lila, for the very same reason, is despised and resented by her other classmates. Elena grows to define herself to a large extent by Lila’s example. “I, I and Lila, we two with that capacity that together – only together – we had to seize the mass of colors, sounds, things, and people, and express it and give it power.”

Ferrante creates a rich, immersive portrait of Elena and Lila, as well as the milieu, the neighborhood and neighbors, of their upbringing. Ordinary events seem elevated, take on an outsized importance. As Ferrante said in an interview, her goal is to create works “where the writing is clear, honest, and where the facts – the facts of ordinary life – are extraordinarily gripping when read.” There really isn’t that much dialogue in the book. Most of it is given over to Elena’s inner monologue, descriptions and analysis of her thoughts and feelings. Continue reading