Darwin

I'm always skeptical when pathologists attempt to diagnose the ills of historical figures. Even if there are medical records or abundant attestations of symptoms from contemporary sources, people in the past had different ways of describing the observations that doctors today collect.

But that doesn't stop people from trying. Last month, John Hayman published a paper in the British Medical Journal that claims a new diagnosis for the lifelong malady that Darwin described in his own journals and correspondence:

Darwin’s symptoms are those of cyclical vomiting syndrome. Although this is primarily a disease of children it may persist into adulthood or may appear for the first time in adulthood. The disease is related to classic migraine and abdominal migraine but is also linked to abnormalities of mitochondrial DNA, with mutations in the MTTL1 gene. This disease is neither well known nor well recognised, particularly in adults, although it was first described in the English literature in 1882.

People with cyclical vomiting syndrome experience abdominal, circulatory, and cerebral symptoms, including headaches and anxiety. Symptoms overlap with those of classic and abdominal migraine, except for a lack of aura. Affected people may experience some or all of these symptoms, with each individual having similar symptoms with each episode. Over time, however, progression or change may occur in the most prominent feature, and episodes may coalesce. Many people report severe motion sickness, and this may be associated with a full episode.

It seems plausible enough, as much so as any retrospective diagnosis could probably be. It bears all the drawbacks of other attempts to diagnose historical figures.

A test of the hypothesis: mtDNA is maternally inherited and haploid, so symptoms are very likely to be shared by maternal relatives:

Darwin’s mother Susannah died with abdominal pain when he was 8. As a child she had vomiting and boils, experienced motion sickness, had excessive sickness during pregnancies, and "was never quite well." Her younger brother Tom had similar symptoms, with headaches, abdominal pains, and motion sickness. A sister, Sarah, considered that Charles and his uncle Tom had the same illness. Evidence of a matrilineal inheritance pattern is good, consistent with an abnormality of mitochondrial DNA.

It's a sad thing to affect a family.

Mitochondrial disorders are increasingly recognized as causes of chronic disease -- just the other day, a new study implicated defective mitochondria as causes of Parkinson's Disease. I think it's hilarious because there is a cadre of geneticists who depend on the notion that mtDNA is a neutral marker of population history.

Darwin's DNA has nothing to say about whether it was neutral on an evolutionary timescale, but every famous mtDNA functional mutation reminds us that there is biological function there, which is a target of selection under some circumstances.

(via Why Evolution Is True)

References:

Hayman JA. 2009. Darwin's illness revisited. Br Med J 339:b4968. doi:10.1136/bmj.b4968

Nature has started a series of essays called "Global Darwin" on the way that Darwin's theory influenced non-Western scientific and political traditions. The first entry, by Marwa Elshakry, puts forward a claim about the reaction of some adherents of Eastern and Islamic traditions to Darwin in the late nineteenth to early twentieth centuries:

Yet the main reason for the worldwide success of Darwin's ideas was the ease with which they were assimilated into local traditions of thought — as the example of the Jewish attempt to reconcile science with scripture hints. Although Darwin himself may have found such reconciliation surprising, it was certainly not as unusual as he might have imagined. Scholars from Calcutta to Tokyo and Beijing constructed their own lineage for the theory of evolution by natural selection, tracing it to older and more familiar schools of thought and claiming ownership of what they saw as the precursors to these ideas. Although some, particularly in Europe, saw Darwin as a weapon beating down religious beliefs, around the world he was as much a force for religious resurgence and revivification as for religious scepticism. Even nineteenth-century Muslim thinkers reconciled Darwinian ideas with their own past religious and philosophical texts; which may seem ironic, given the rise of Muslim creationists today.

I didn't find the whole of this essay to be very satisfying. It does provide a few interesting examples of individuals making statements about Darwinism in integrative ways. But the essay does not look at the integration of Darwinism into the biology or naturalist traditions of non-Western cultures. I think that a close examination would be necessary to separate the political overtones of Darwinism -- broadly, an argument in favor of progress -- from the actual reception to the theory by people in a position to understand it.

As it is, Elshakry shows that some reformers favored a "Darwinian" approach to social change, as a bulwark against more revolutionary ideas. Such arguments did exist, but I think it's worth remembering that Marxism was based on its own evolutionary theory -- elevated to quasi-Darwinian status by some social thinkers -- and was broadly a defense of violent overthrow of the existing order. At the same time, Darwin's theory was part of the Western intellectual tradition that threatened to impose hegemony over non-Western cultures, so a resistance to Darwinism was a possible avenue of nationalism. Certainly that plays a role in the late twentieth-century resurgence of creationism in the Islamic world, as well as the rejection of Darwin/Mendelian inheritance by Stalin's USSR. It would be interesting to see how that dynamic plays out in other contexts.

My point: many have deliberately confused aspects of biological theories (including evolution) with social change, which is an error. Giving a list of interesting errors might make for a great essay, but mixing them with the general theme of "assimilation" apparently didn't.

References:

Elshakry M. 2009. Global Darwin: Eastern enchantment. Nature 426:1200-1201. doi:10.1038/4611200a

Michael Balter reports on the historical work of Alex Menez, at the Gibraltar Museum: "When Darwin Met a Neandertal".

Darwin’s reaction is recorded simply in a 1 September 1864 letter to his close friend, botanist Joseph Hooker: “F[alconer] brought me the wonderful Gibraltar skull.” As Menez put it: “We can imagine Darwin holding the skull, peering enthusiastically at its well-marked brow ridges, his own eyes beneath brow ridges that were themselves significantly larger than those of most people!”

Darwin had encountered both Australian and Fuegan aborigines, and may therefore have been more well-equipped than almost any of his contemporaries to think about the place of the browridge in human variation. But as Balter (and Menez) describe, we can tease out almost nothing about Darwin's thoughts on this matter.

I'm fascinated by the date. In May 1864, Darwin had been sent a copy of Wallace's paper on human origins, which appeared in the Anthropological Review. He reacted to this in the last week of May, trading letters with Hooker and Wallace, both expressing his praise for Wallace's "genius" and his disagreement with a few points. Darwin had been famously silent on the topic of human evolution in the Origin, leaving Wallace to take up the subject. I'll have more to say about that later; right now I just thought I would point out that Wallace referred directly to the Neander valley skull:

The Neanderthal skull may be a specimen of one of the lowest races then existing, just as the Australians are the lowest of our modern epoch.

Not too encouraging, I guess. Nobody ever loved them. Although he does not say so explicitly, Wallace seems to have accepted that rough contemporaries of the Neandertals belonged to a more modern race (he mentions Denise and Engis as examples that "agree so closely with existing forms", the Engis skull is now recognized as a subadult Neandertal).

Darwin's letter referring to the Gibraltar skull is online at the Darwin Correspondence Project website. My favorite part is in the DCP footnote:

In September 1864 the British Association for the Advancement of Science awarded Busk and Falconer a grant of £150 to further their researches on the remains.

Oh, yes. £150 used to be a lot of money. Nowadays it might just buy a cast of the skull.

John Scalzi hits on a formula to get wide U.S. distribution for Creation (the producers are complaining that they can't find a distributor):

Maybe if Charles Darwin were played by Will Smith, was a gun-toting robot sent back from the future to learn how to love, and to kill the crap out of the alien baby eaters cleverly disguised as Galapagos tortoises, and then some way were contrived for Jennifer Connelly to expose her breasts to RoboDarwin two-thirds of the way through the film, and there were explosions and lasers and stunt men flying 150 feet into the air, then we might be talking wide-release from a modern major studio.

RoboDarwin

It's a funny riff on a pretty obvious problem: Who's going to go watch it? I'm interested in the topic of the movie because there are few that touch on human evolution at all, but I'm not sure I'm interested enough to go and see it. A nineteenth-century costume drama about a dying child and a man's struggle with faith and guilt about cousin marriage -- I'm pretty sure if that came on Masterpiece Theatre, I'd turn the channel. Does it matter if it's Darwin? I'd like to think that it gave the writers a chance to make it interesting, but from what I've seen so far I have little hope of that.

Anyway, this is precisely the time that the producers are bargaining with possible distributors, so they have every incentive to try to get as much free marketing as they can, and as we all know controversy sells. A blockbuster movie is seen in theaters by fewer than 15 million Americans. A decent-grossing Oscar contender is seen by fewer than 3 million -- not one person in a hundred. There have been plenty of movies that are openly hostile to the majority of people that get distribution and make a lot of money, because only a narrow few have to actually go to the theater. The trick is motivating those few.

In this case, the producers have decided to get people to take their medicine by convincing them that their neighbors are getting worse.

It's probably a marketing win. Probably moreso than the RoboDarwin version. Heck, "Homo erectus" the movie -- which started out as a fairly successful stage play, and ended up rebranded as "National Lampoon's Stoned Age", direct to DVD. It had all the things that American audiences love -- sight gags, bawdy jokes, Ron Jeremy -- hey, it's "prehysterical"! That was a marketing fail.

The Fitzwilliam Museum, Cambridge UK, is putting on an exhibition titled, "Endless Forms: Darwin, Natural Science and the Visual Arts."

The exhibition is accompanied by a well-produced webiste, which includes descriptions of the collection, some material for educators (including visit information for the UK), and a virtual exhibition. Some of the text may be stretching Darwin's direct influence on the arts -- a naturalistic eye goes back farther than Audubon, for example, but several sections are interesting. Here's an excerpt from "Darwin and the Impressionists":

Edgar Degas, too, is known to have engaged directly with Darwinian theory, especially through reading Expression of the Emotions in Man and Animals soon after it was published in French in 1874. His images of dancers, singers, and criminals in the decades that followed stressed a kinship with animals in their features and gestures, and hinted at the possibility of human degeneration to an animal condition.

I think it's an open question how much Darwinism really affected popular culture. Several of the artists represented (e.g., Robert Farren) were already representing ancient creatures well before the publication of the Origin. Artists seem to have reacted to a greater understanding of nature, and science drew on that art as well as upon itself.

(via Jeff Hayes)

UPDATE (2009/06/23): I should mention that the BBC has a slideshow based on the exhibition. It doesn't have as much material, but it does have nice big versions of some of the included artwork. Plus, kinda depressing classical music.

No, that's not a snark on Jennifer Connelly. Although she was in Labyrinth...

A release from ScienceDaily has a headline I can't resist:

Darwin Killed Off The Werewolf

It was Darwinian theory that did away with the werewolf. For much of recorded history, humans have reserved their greatest fears for dog-human hybrids like the werewolf. These beasts were once thought to be real, hiding behind every tree waiting for the unsuspecting traveler.

But, argues Brian Regal, assistant professor of the history of science at Kean University in Union, New Jersey, USA, the publication of Charles Darwin’s On the Origin of Species 150 years ago focused minds on a different kind of monster – ape-men such as the Yeti, Bigfoot and Sasquatch.

That's an interesting take on it. I think that greater contact with exotic places, including exhibitions of apes, probably had more influence than Darwin's ideas. Nineteenth-century travelogues and lectures caused a sensation with their description of gorillas and chimpanzees. Later on, people started to record myths and stories of indigenous peoples -- including Sasquatch, ebu gogo, orang pendak, and others. Those raised the possibility of unknown creatures in unexplored parts of the world. Meanwhile, industrialization and associated development markedly reduced the potential that supernatural creatures were roaming Europe.

Still, if public education about hybridity made a difference, so much the better!

(via Gene Expression)

Now, usually if I were to say "anti-Darwinists", I'd be talking about some kind of creationism or intelligent design. But noooooo. This week, the anti-Darwinists are all otherwise respectable evolutionary biologists using the occasion of Darwin's bicentennial to trash the man.

The one that has me writing is an essay in the NY Times by Carl Safina:

But our understanding of how life works since Darwin won’t swim in the public pool of ideas until we kill the cult of Darwinism. Only when we fully acknowledge the subsequent century and a half of value added can we really appreciate both Darwin’s genius and the fact that evolution is life’s driving force, with or without Darwin.

Is Darwinism a cult? Does this kind of statement remotely help the cause of evolutionary biology, in any way?

Now, I can understand the argument. Naming a modern science after a nineteenth-century geezer is probably not the best PR move. If a scientific idea is known mostly by the name of its founder, it is almost invariably wrong. Newtonism? Wrong. Lamarckism? Wrong.

Moreover, all the "right" ideas have impressive names. Do we talk about Boltzmannism? Heck no, it's thermodynamics. Wundtism? Nope -- that's experimental psychology. What about Einsteinism? Sorry, relativity.

Darwinism is like the only holdout. And honestly, I don't know any evolutionary biologists who call their field "Darwinism". They call it, well, "evolutionary biology."

"Darwinism", like "Trotskyism" and "Marxism", is the kind of name that sounds like it was coined by someone writing an enemies list. And it was. Certain creationists spit it like a bad wad of chaw.

But there's something unseemly about the anti-Darwin bandwagon:

That all life is related by common ancestry, and that populations change form over time, are the broad strokes and fine brushwork of evolution. But Darwin was late to the party. His grandfather, and others, believed new species evolved. Farmers and fanciers continually created new plant and animal varieties by selecting who survived to breed, thus handing Charles Darwin an idea. All Darwin perceived was that selection must work in nature, too.

Oh, well then. If that's all he perceived, let's by all means kill the dead man. Really, kill him?

The ninth-century Buddhist master Lin Chi said, “If you meet the Buddha on the road, kill him.” The point is that making a master teacher into a sacred fetish misses the essence of his teaching. So let us now kill Darwin.

Here's my problem. People who say that Darwin didn't have many ideas usually haven't read any Darwin. Now, I might say this about many nineteenth-century thinkers. When you go through the works of Spencer, or Haeckel, or Wundt, you discover that these people were remarkably thoughtful. They went through reams of examples -- the kind of writing you rarely see people do anymore. Darwin was one of this number, perhaps the foremost. So it should come as no surprise that his works were full of details that would precipitate or presage developments as much as 150 years later.

But there's something more. Darwin threaded many needles in his writing, finding the right solution for many contradictions -- not only in his naturalism but also in the way his theory provoked social resistance. Darwin had the first theory of human evolution. It wasn't correct, as we now know, but it did the essential thing: it showed a way that human features could have emerged by natural pressures of the environment. Darwin found a plausible explanation for the diversity of races -- one not rooted in the divine order, but in natural history. He championed the monogenetic theory against polygenists who held that human races had separate origins. And he integrated the best empirical data from animal and plant breeding into the understanding of the natural world. Possibly most important, he insisted on the testability of his hypotheses, and gave specific criteria that would falsify them.

Sure, many of Darwin's ideas now seem obvious. When different varieties have different rates of intrinsic growth, one will inevitably supersede the others. Small changes add up to big changes over long times. Common descent explains common morphology.

But it is precisely the reams of details that remind us so forcefully that there is more to being a scientist than having good ideas. You also have to have the courage to tell the world exactly how your ideas could be rejected. We have rejected many of Darwin's in the succeeding 150 years. Still the core remains.

If someone want's to call herself a Darwinist, or a neo-Darwinist, or even a crypto-Darwinist, well, that's just fine by me.

I will be giving two public lectures out of town later this week.

The biggest is this Thursday evening, February 12, when I will be giving the Darwin Day lecture at the University of Wisconsin-Whitewater. This is a really great venue, and I'm really looking forward to it! So I'm bringing out all the good stuff:

Neandertals, Darwin and the Sicilian Mafia: What do they have in common?

If you're in the SE Wisconsin area, the lecture is Thursday 2/12, at 7:00 pm, in the Young Auditorium at UWW.

Earlier in the week, on Wednesday, I'll be giving a lecture in the Human Genetics department at the University of Chicago. This talk will cover some of my current research on recent selection in humans, as well as the connections between our evolutionary history and documented written history. The title is:

Spatial dynamics of positive selection, language dispersals, and human history

If you're familiar with UC, you're ahead of me in finding the place. The talk will be Wednesday 2/11, at 4:00 pm in CLSC 101.

This Saturday, February 7, is Darwin Day at the University of Wisconsin-Madison. The official site is online, including the full schedule of the day's activities.

I will be giving a short presentation in the afternoon session, around 1:30 or so, covering my work on the evolution of hearing and language in humans. With the participation of my great graduate students, we're also planning to have some hominid casts for the exploration stations in the afternoon.

Meanwhile, there are other very interesting events. The morning presentations by evo-devo expert Sean Carroll, zoologist Patricia McConnell, and Jeremy Jackson of the Scripps Institution of Oceanography should be really good. And there's a panel in the afternoon covering science in the media, featuring James Crow, Steve Paulson of Wisconsin Public Radio, Jeremy Jackson and Molly Jahn.

The Wisconsin State Journal has published a nice article about the events:

To Tony Goldberg, a professor in the University of Wisconsin-Madison’s School of Veterinary Medicine, the concept of evolution is far from a dusty theory. It’s a real process that informs just about everything he does in his laboratory.

Goldberg studies the ecology and evolution of disease and disease-causing organisms and he sees evolution every time he studies a virus or a bacteria that has changed to resist our latest efforts to control it.

"People would be surprised," Goldberg said, "at how deeply evolutionary biology affects our everyday lives."

This is the start of a busy week for me, as I will be giving a lecture in Chicago next Wednesday and at UW-Whitewater next Thursday evening. I'm looking forward to both those events as well, and will post later with some more information if you're in either area.

The New York Times today reviews a new book by Adrian Desmond and James Moore, titled Darwin's Sacred Cause: How a Hatred of Slavery Shaped Darwin's Views on Human Evolution.

Darwin’s power, according to Desmond and Moore, lay in his marshaling an argument for the unitary origin and hence “brotherhood” of all human beings, and this, they argue, is precisely what Darwin achieved in “The Origin of Species” and later in “The Descent of Man.” The case they make is rich and intricate, involving Darwin’s encounter with race-based phrenology at Edinburgh and a religiously based opposition to slavery at Cambridge. Even Darwin’s courtship of Emma, whom he winningly called the “most interesting specimen in the whole series of vertebrate animals,” is cleverly interwoven with his developing thoughts on “sexual selection,” the aesthetic preference for certain traits, like skin color in humans or plumage in peacocks, that over time leads to those super ficial variations we mistakenly think of as “racial.”

But what if Darwin’s evidence had led to conclusions that did not support his belief in the unitary origins of mankind? Would he have fudged the data? Desmond and Moore don’t really address the question. One is left with the impression that Darwin was amazingly lucky that his benevolent preconceptions turned out to fit the facts.

Well, maybe so, although a read of the Voyage of the Beagle doesn't leave one with warm feelings for the brotherhood of mankind. Here's a passage from pp. 580-581 of the Voyage (1839, emphasis mine):

Wherever the European has trod, death seems to pursue the aboriginal. We may look to the wide extent of the Americas, Polynesia, the Cape of Good Hope, and Australia, and we shall find the same result. Nor is it the white man alone, that thus acts the destroyer; the Polynesian of Malay extraction has in parts of the East Indian archipelago, thus driven before him the dark-coloured native. The varieties of man seem to act on each other; in the same way as different species of animals—the stronger always extirpating the weaker. It was melancholy at New Zealand to hear the fine energetic natives saying, they knew the land was doomed to pass from their children. Every one has heard of the inexplicable reduction of the population in the beautiful and healthy island of Tahiti since the date of Captain Cook's voyages: although in that case we might have expected it would have been otherwise; for infanticide, which formerly prevailed to so extraordinary a degree, has ceased, and the murderous wars have become less frequent.

There are certain passages in Darwin's work that are difficult to explain, if you're a scholar committed to the idea that "social Darwinism" was an evil bastardization by Herbert Spencer. Darwin was not a saint; he was a product of his times. He depended upon his readers' common knowledge as a way to push his observations and hypotheses forward.

In fairness to Darwin, his mode of explaining the state of affairs for indigenous peoples in the Voyage was generally to point out that many of their problems were caused by whites. On page 533, he describes the fate of the Tasmanians:

All the aborigines have been removed to an island in Bass's Straits, so that Van Diemen's Land enjoys the great advantage of being free from a native population. This most cruel step seems to have been quite unavoidable, as the only means of stopping a fearful succession of robberies, burnings, and murders, committed by the blacks; but which sooner or later must have ended in their utter destruction. I fear there is no doubt that this train of evil and its consequences, originated in the infamous conduct of some of our countrymen. Thirty years is a short period, in which to have banished the last aboriginal from his native island,—and that island nearly as large as Ireland. I do not know a more striking instance of the comparative rate of increase of a civilized over a savage people.

Mere equanimity would mark Darwin as a progressive compared to many of his contemporaries; he does much better than that with a generally sympathetic view of other peoples. But it would be a stretch to say his commitment to monogenism was unusual or courageous. Although there were many prominent polygenists (those who believed the human races had separate origins, accounting for their antiquity and diversity), monogenism was the default in the nineteenth century for both religious authorities and natural historians.

Fig. 20 from Darwin 1872. "Terror"

While I was out of town for the holidays, a news story by Jeanna Bryner reported on research that looked at the facial expressions of blind Paralympians:

The analyses showed sighted and blind individuals modified their expressions of emotion in the same way in accordance with the social context. For example, in the Paralympics, the athletes competed in a series of elimination rounds so that the final round of two athletes ended in the winner taking home a gold medal while the loser got a silver medal.

The blind silver medalists who lost their final matches tended to produce "social smiles" during the medal ceremonies. Social smiles use only the mouth muscles. True smiles, known as Duchenne smiles, cause the eyes to twinkle and narrow and the cheeks to rise.

The "social smile" is interesting because it seems like a way of concealing emotions from others. The conclusion was that visual learning could not account for the socially correct use of these expressions, since people blind from birth follow the same rules.

When I read this story, I couldn't help but reflect on Darwin's description of facial expressions, in The expression of the emotions in man and animals. By taking up this topic, Darwin set out on new mode of psychological investigation, distinct in many ways from the experimental psychology tradition. In fact, the major figures in German experimental physiology, such as Wundt, are never mentioned in Expression. This clean separation may have been Darwin's deliberate attempt to establish psychological inquiry on new ground; his intent was marked in the last section of the Origin:

In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history (Darwin 577-578).

Darwin was not alone in pursuing a comparative approach and insisting on continuities between humans and other animals. In some details he followed Herbert Spencer's psychology. George Romanes picked up Darwin's own notes on animal behavior as he began to systematize the field; his Animal Intelligence ranged in its examples from invertebrates to man's best friend, the dog.

Darwin also spends substantial parts of Expression on the expressions of dogs. His analysis, like his description of sexual selection in The descent of man presages later work on signaling. But Darwin's human examples are some of the most interesting in the book. The picture at the top of this post was drawn "from a photograph by Duchenne" -- the same Duchenne (Guillaume-Benjamin-Amand de Boulogne) whose name is commemorated by the "Duchenne smile" as well as the eponymous muscular dystrophy. Duchenne was an experimental physiologist, who among other things used electrical stimuli to contort the facial muscles into their characteristic expressions.

Darwin used the photograph above in Expression, along with others of the same experimental subject. The experimenter at right is Duchenne.

Darwin had other means of obtaining information that the current researchers of Paralympians lack. For instance:

Dr. W. Ogle observed for me in one of the London hospitals about twenty patients, just before they were put under the influence of chloroform for operations. They exhibited some trepidation, but no great terror. In only four of the cases was the platysma visibly contracted; and it did not begin to contract until the patients began to cry. The muscle seemed to contract at the moment of each deep-drawn inspiration; so that it is very doubtful whether the contraction depended at all on the emotion of fear. In a fifth case, the patient, who was not chloroformed, was much terrified; and his platysma was more forcibly and persistently contracted than in the other cases. But even here there is room for doubt, for the muscle which appeared to be unusually developed, was seen by Dr. Ogle to contract as the man moved his head from the pillow, after the operation was over. (Darwin 1872:300-301).

His subsequent discussion is interesting, begun with a characteristic Darwin question: "...I felt much perplexed why, in any case, a superficial muscle on the neck should be especially affected by fear...."

Darwin particularly sought to distinguish the unconscious signs of emotions from the deliberate, and the culturally variable from the universal. In a time when the study of cultural variability was just beginning, Darwin does an admirable job.

His explanations of unconscious expressions presage some of the writings of behaviorists, notably John Watson:

Through steps such as these we can understand how it is, that as soon as some melancholy thought passes through the brain, there occurs a just perceptible drawing down of the corners of the mouth, or a slight raising up of the inner ends of the eyebrows, or both movements combined, and immediately afterwards a slight suffusion of tears. A thrill of nerve-force is transmitted along several habitual channels, and produces an effect on any point where the will has not acquired through long habit much power of interference. The above actions may be considered as rudimental vestiges of the screaming-fits, which are so frequent and prolonged during infancy.

In this case, as well as in many others, the links are indeed wonderful which connect cause and effect in giving rise to various expressions on the human countenance; and they explain to us the meaning of certain movements, which we involuntarily and unconsciously perform, whenever certain transitory emotions pass through our minds.

Darwin did discuss the issue of Duchenne smiles and false smiles in Expression. Here is a redacted section from pages 203-204:

Dr. Duchenne has given a large photograph of an old man (reduced on Plate III. fig 4), in his usual passive condition, and another of the same man (fig. 5), naturally smiling. The latter was instantly recognised by every one to whom it was shown as true to nature. He has also given, as an example of an unnatural or false smile, another photograph (fig. 6) of the same old man, with the corners of his mouth strongly retracted by the galvanization of the great zygomatic muscles. That the expression is not natural is clear, for I showed this photograph to twenty-four persons, of whom three could not in the least tell what was meant, whilst the others, though they perceived that the expression was of the nature of a smile, answered in such words as "a wicked joke," "trying to laugh," "grinning laughter," "half-amazed laughter," &c. Dr. Duchenne attributes the falseness of the expression altogether to the orbicular muscles of the lower eyelids not being sufficiently contracted; for he justly lays great stress on their contraction in the expression of joy.

He goes on to examine the muscles involved in the expression with more detail. Darwin's concern was to connect the smiles of humans with expressions of other primates, and to connect the actions of the facial muscles in a rational way. For example, Darwin suggested that the zygomatic muscles contract during pleasurable emotions, and attempted to relate the characteristic expressions of mental patients having delusions of grandeur to that pattern. Elsewhere, he examines the "grins" of dogs and their relation to play, as well as various reports of smiles in non-human primates.

So, I doubt Darwin would have been surprised by the research on blind athletes.

References:

Darwin CR. 1872. The expression of the emotions in man and animals. John Murray, London.

Darwin CR. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. John Murray, London. 5 ed.