Tuesday, December 8, 2009

Milestone Birthdays – Looking Back with Darwin

Milestone birthdays – the ones with nice, round numbers attached to them – can lead to reflection and reassessment, that’s their curse. Lengthy ruminations, such as this one, are also part of the downside.

Darwin’s 30th Birthday

In this the Year of Charles Darwin, it’s only appropriate to observe that 170 years ago he had a 30th birthday that should have pleased him. A wave of public and private successes had deposited him in 1839 on high scientific and social peaks. Just in the month and half between the beginning of that year and his birthday on February 12th, he’d secured election to the Royal Society of London (joining a very select group of influential scientists from around the world); had his first full, formal scientific paper accepted by, and read before, the same Royal Society; and married Emma Wedgwood. So, with good reason, any reflection in which he may have indulged probably generated a great deal of satisfaction at what he had achieved. Though, I suspect, in keeping with his natural inclinations, any happiness would have been tainted with concern about how demanding his work was and how poorly he felt.

My Milestone Birthday

I recently marked one of those milestone birthdays (not my 30th, by the way). Basic conclusion of my reflection and stock-taking is that I’m still an amateur at all of this, having gotten some things right and others . . . well, not so right. Frankly, lots of it in retrospect seems to be a muddle. Where are the bright lines? I am the Englishman in the scene at the beginning of Casablanca (link to full script). (Appropriately, that movie, like life, was assembled on the fly, with dialogue being composed for scenes even as they were being filmed.) Here’s the scene:

It’s Casablanca during World War II. The local police, in search of the murderer of two German couriers, are herding arrested suspects (the “usual suspects”) into the “Palais de Justice.” A middle aged English couple sits at a nearby cafe watching these events.

The husband turns to his wife and asks, “What on earth’s going on there?”

She responds, “I don’t know, my dear.”

A European of unknown nationality comes over and says, “Pardon, pardon, Monsieur, pardon Madame, have you not heard?”

The Englishman replies, “We hear very little, and we understand even less.”

Redefining One’s Self

Tom Boswell, the Washington Post sportswriter, had an interesting column in the December 4, 2009, issue of the paper (A Portrait of the Golfer As a Man, December 4, 2009). For this blog posting, it’s irrelevant that his piece was about Tiger Woods. Relevant is Boswell’s key premise that, just as our image of a person’s public persona can transform dramatically over time, for better or worse (such as Bill Gates from “self-centered monopolist” to humanitarian philanthropist), so too does how we view ourselves change. As Boswell puts it,

We spend our lives drawing and re-drawing the portraits of everybody we know – our family, friends, colleagues and, of course, those public figures that interest us most. We even redraw our own self-portraits.

It’s that redefining of one’s self that I’m mulling over. Milestone birthdays are a good time for seeing if there’s a different answer to the question, “Who am I now?” Sometimes the very events that we considered to be ones that defined who we are turn out, over time, not to be so critical, or, perhaps, we draw a different meaning from them. In my case, the decision to change my life’s work was a redefining moment if there ever was one. The new career, in my mind, was what most prominently identified me . . . well, that is, until the new career failed to “take.” With the passage of time, I now see the act of change as a defining aspect of that decision. Hey, if I did it once on such a large scale, I can do it again . . . even if I don’t. The alternative is to view the episode as a failure and dwell on it. I choose not to.

It must be particularly hard when defining events are carried out on a very public stage. That was certainly the case for Darwin and one of those central accomplishments from the beginning of 1839. When, in his case, the venue was the scientific world writ large, the transformation of a presumed success into a colossal embarrassment (at least, in his eyes) must have been particularly hard to acknowledge (and it took him a long time to do so publicly), much less understand. However painful it remained over the years (and it did), the failure itself may have actually transformed him as a scientific theoretician.

Glen Roy

In the summer of 1838, Darwin took what he called “my Scotch expedition,” which included a sustained examination of the “parallel roads” at Glen Roy in Scotland. These roads are a series of three very straight, parallel terraces or shelves on the slopes on either side of the valley at Glen Roy. Each terrace has a counterpart on the slope across the valley.

The first picture below on the left shows the three terraces -- the straight lines cutting across the slopes (image courtesy of http://www.undiscoveredscotland.co.uk/). The second picture shows one of the terraces in profile, while, across the valley, terraces on the far slopes are partly shrouded in the fog (image posted at http://www.geograph.org.uk/photo/243017,copyright by Andy Spenceley and licensed for reuse under a Creative Commons License.)

A trip to Glen Roy and hazarding theories to explain the creation of the parallel roads seem to have been a sort of rite of passage for many geologists or aspiring geologists of the period. Of course, non-scientific explanations abounded. According to University of Edinburgh environmental historian Jan Oosthoek, Gaelic legends ascribed the roads to fairies or to Fingal, the Celtic giant. Locals also asserted that the kings of Scotland built them. [The Parallel Roads of Glen Roy and Forestry at http://www.eh-resources.org/roy.html]

Writing to the preeminent geologist Charles Lyell (August 9, 1838), Darwin described how Glen Roy “astonished” him. The general landscape of Glen Roy and its environs were “far the most remarkable area I ever examined.” Amazing words from the man who had sailed on the Beagle. As for the parallel roads, Darwin went with something other than fairies or kings. Here’s what he concluded in his letter to Lyell:

I have fully convinced myself, (after some doubting at first) that the shelves are sea-beaches,-although I could not find a trace of a shell, & I think I can explain away most, if not all, the difficulties.

He added,

I am now employed in writing a paper on the subject, which, I find very amusing work, excepting that I cannot anyhow condense it into reasonable limits. At some future day I hope to talk over some of the conclusions, with you which the examination of Glen Roy has led me to.

An Aside – Darwin’s letters are a delight. It’s so easy to be drawn away from your research objective as you read them. For his “Scotch expedition,” Darwin traveled by ship to and from Scotland and told Lyell that he was particularly pleased with himself because he had not become seasick. As he put it, on the trip to Scotland, “I enjoyed the spectacle, wretch that I am, of two ladies & some small children quite sea sick, I being well. Moreover on my return from Glasgow to Liverpool, I triumphed in a similar manner over some full grown men.” Classic. It’s also easy to do research with the letters because of the online treasure trove that is the Darwin Correspondence Project. All of the letters cited in this posting are available from the Project. Over the past 35 years, the Project has located and published transcriptions of Darwin’s correspondence, letters from him, as well as letters to him. Information about, if not full transcripts, are available for some 15,000 letters.

Throughout the rest of 1838, Darwin labored on his Glen Roy paper, ultimately promising Emma that he would finish it before their wedding date. In a letter to her dated January 6, 1839, he wrote:

For the last three days, I have been working very hard at my Glen Roy Paper-the three day’s moving of my goods rested me almost as much as a visit in the country,-I have finished 65 pages & have only fifteen more, so I think I shall have done them by Wednesday.- [It was Sunday when he wrote to her.]

Darwin apparently kept to that schedule, enclosing a copy of the paper with a letter to Lyell, that is dated around January 9th. One senses that, though he wanted to be done with it, he was extremely proud of it. The letter to Lyell opens with a declaration that the paper is inviolate, despite its length. And it’s not hard to hear the false modesty in the second paragraph.

I send my Glen Roy paper, which thanks to Providence I have at last finished.- I hope the Secretary [of the Royal Society] will not grumble at its appearance.- it is all legible, although some pages look a little ugly from my corrections. Regarding its length, I devoutly trust they will not ask me to shorten it, for long as it is, I believe there is scarcely a sentence, that I have not considered whether I could strike it out, without injuring the general argument.-

If you think it worth your while to keep it & read it, pray detain it just as long as you like,-but I doubt whether it is your worth while.-

The Royal Society received the paper entitled, Observations on the parallel roads of Glen Roy, and of other parts of Lochaber in Scotland, with an attempt to prove that they are of marine origin, on January 17th and it was read on February 7th. A week after the paper was received, Darwin was elected a fellow in the Royal Society.

What was in question for the terraces at Glen Roy doesn’t seem to have been the agent responsible for creating them, rather, it was the nature of that agent. In the paper, Darwin acknowledged the consensus that the terraces resulted from the action of water on the mountainsides. But, he categorically rejected the theory, previously presented to the Royal Society, that lakes had occupied each of the several valleys in the area. He wrote,

It is a startling assumption to close up the mouth of even one valley by an enormous imaginary barrier; to do this with all would be monstrous. Of such barriers in the district we are considering I need not say there does not exist any trace . . . .

Instead, Darwin asserted these various valleys had been occupied by fingers of a sea. David Dobbs in his engrossing book Reef Madness: Charles Darwin, Alexander Agassiz, and the Meaning of Coral (2005) summarizes Darwin’s argument as follows (p. 33):

Here at Glen Roy, . . . Darwin saw not subsidence [which he identified in South America] but uplift. Specifically, he theorized that the entire valley had once been at or under sea level and that the three sets of terraces were former shores that rimmed a saltwater sea or inlet as the land rose in three subsequent surges.

What a heady moment it must have been, that 30th birthday. But, a year later, Louis Agassiz, the Swiss scientist, visited Glen Roy and summarily dismissed Darwin’s theory. As the leading thinker on glaciers and previous ice ages, Agassiz saw clear evidence that glacier ice had plugged the valley at Glen Roy, creating a glacial lake. The melting of the ice in three stages had left shorelines etched along the length of both sides of the valley.

Though he fought long against Agassiz’s theory, Darwin probably recognized it was a losing battle well before he publicly acknowledged he was wrong. A June, 1848 letter to publisher and geologist Robert Chambers suggests what an emotional rollercoaster the Glen Roy paper had become for Darwin and how invested he was in its success:

I will first make some remarks on Glen Roy, which is a subject that has always interested me beyond perhaps its just merit, & about which I feel much a personal interest, for I shd have been more sorry to have been proved wrong on it, than upon almost any other subject. Mr Milne, as you know, at first staggered me in favour of the glacier view, but I had quite recovered that & had resumed my old state of positiveness. . . . All this, I think, has made me the more pleased with your coming to the same conclusion as I did.

But, after a two decade effort to defend it, he finally threw in the towel. Following a visit to Glen Roy, geologist Thomas Francis Jamieson sent Darwin a letter in early September, 1861 which made a convincing case for the valley having been blocked by glaciers. In addition to the many features that said glacier to him were others that argued persuasively against the influx of a sea in the area.

To this letter, Darwin replied on September 6th:

I thank you sincerely for your long & very interesting letter. Your arguments seem to me conclusive. I give up the ghost. My paper is one long gigantic blunder.

. . . I have been for years anxious to know what was the truth, & now I shall rest contented, though ashamed of myself.-

Darwin was certainly gracious in acknowledging defeat, though he was mightily chagrined, and it continued to rankle. In an autobiographical piece written in 1876 (as printed in Charles Darwin: His Life Told in an Autobiographical Chapter, and in a Selected Series of His Published Letters, edited by Francis Darwin (1902)), he called the paper “a great failure” and wrote, “I am ashamed of it.”

So, one of the crowning glories of his 30th year proved otherwise. It was a stinging defeat that remained painful. He described the lesson it taught him in his letter to Jamieson in 1861 – in effect, he wrote, he’d rejected one explanation for a natural phenomenon and assumed that the correct one simply had to be the one that fit with his current state of knowledge. He later restated the lesson in his autobiography – “never to trust in science to the principle of exclusion.”

But, perhaps it really takes a neutral party to describe the full impact of such a defining (redefining) moment. David Dobbs writes of the consequence of this defeat for Darwin the theoretician (p. 36):

. . . Darwin's long, slow defeat on Glen Roy led him to test his theories more rigorously and hold himself to a higher level of proof. This lesson, added to his habitual caution, doubtless contributed to his twenty-three-year hesitation in publishing his theory of evolution. . . . [It] helped Darwin to forge the distinctive theoretical approach – imaginative in spawning ideas, rigorous in testing them.

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