Greg Laden has a big advantage over me

He was probably able to get home before midnight last night. You can now read his description of the social events around Dawkins’ visit, and a much more thorough account of the talk itself.

One other point that I should emphasize. This talk presented an overview of how we should look at the appearance of design in the universe, for a general public. While I heard some complaints that there was nothing new in it, that’s the way this had to be: it was a synthesis of a position.

Dawkins is often given a rap as one of those ultradarwinians who see every detail of life as the explicit product of carefully honed selection. For me, what was interesting in this talk was how clearly he repudiated that position. In several places, he contrasted what he called a “naive Darwinist” perspective with reality, and showed that the strawman didn’t hold up. A major point was also that features that may very well have evolved with a core that was selected for can have side-effects, and been subverted to non-adaptive purposes, and that these features may represent a significant element of the species’ character. He talked quite a bit about the flexibility of the human brain, a property that was the product of selection, yet that same flexibility means it can be reprogrammed into deleterious byways, such as religion or fanaticism or unthinking patriotism.

It was all stuff that I agreed with, and didn’t surprise me at all. Similarly, The God Delusion didn’t contain anything radical or new. The virtue of these kinds of talks and books is that they pull many commonly held ideas together into a coherent fusion that can be more readily absorbed by a larger number of people who haven’t yet taken in all of the underlying evidence.

Wild night on the town for a godless nerd

I may be getting too old for this.

Yesterday, I finished up teaching at 1 in the afternoon, then had to leap into the Pharyngulamobile and drive, drive, drive to Minneapolis. I got together with Lynn Fellman and Greg Laden for a hasty dinner before I had to go move my car and park prior to Richard Dawkins’ talk. This was almost a disaster; it turns out that last night, at the same time as the talk, there was a basketball game scheduled. The streets were packed, parking was a nightmare, and I only got to Northrop Auditorium with a whisker of time to spare. Many of the attendees seem to have run into the same problem, as I noticed that people were dribbling in well into the middle of the talk. (No, not dribbling large orange balls…dribbling as in trickling, and looking a little stressed from the struggle to get into the parking garages.)

I introduced Dawkins almost on time, though. I got applauded, even though I only spent less than a minute talking — or maybe because I spent less than a minute talking.

Dawkins’ talk was good. He’s trying to make a strong distinction with a word that’s already greatly overloaded in the English language: “purpose”. His point was clear, that we really can mean a lot of very different things when we describe the purpose of something, and that especially when we’re talking about biology, “purpose” does not imply “designed with intent”. One excellent example of the way “purpose” is abused was shown: Ray Comfort’s infamous banana rationalization. It made the bit even more hilarious to see after Dawkins had warned us of the habit of too many people to use “purpose” too freely to imply intent — Comfort was the perfect bad example. I’m a bit dubious that Dawkins’ word coinages — “archi-purpose” for describing the function of an evolved structure, like a bird’s wings, and “neo-purpose” for novelties produced as a consequence of prior innovations, and which are often subverted to undermine a Darwinian function — but that’s always the problem with attempts to introduce new terms. Language is a slippery beast that will twist beneath your efforts to tame it.

Dawkins did do a book-signing afterwards, at which a huge crowd appeared. I was very impressed at the man’s well-practiced signing technique — he got through everyone quickly, and he didn’t seem to suffer the slightest crippling of the wrist for his trouble.

We then had a pub night, at the Campus Club in Coffman Memorial Union. As you know, we’d kept it a bit mum so we wouldn’t be overwhelmed by a swarm descending on the place, but just by word of mouth we had well over a hundred people in attendance. Richard got his beer, I had non-alcoholic stuff (no fun, but I had a long drive ahead of me), and there was a buffet of good food that vanished amazingly fast. All thanks to Rick Schauer who set up and hosted the event! We had more mobs of people swarming Richard and getting photos taken with him; look for them to bloom all over Facebook today. It was a good opportunity to make a more informal acquaintance with the famous Dr Dawkins than the usual lecture followed by departure, so if you didn’t get the super-semi-secret directions to the party, you missed out on a splendid evening.

We wrapped up and left about 11pm. I know, the night was still young! Alas, I had a three hour drive home ahead of me. I survived it, got home, passed out…briefly. Now I’m up getting ready for my 8am class. Fortunately, it’s student presentations today, so I just have to be awake enough to listen attentively. Have pity on one of my students in that class (Hi, Levi!) who was also in attendance last night, and has to describe frequency shifting in bat calls this morning. It’s good practice for the madcap life of the scientist!

Of course, I’m older than my students. I may just have to drag myself into a dark corner after class and fall into a coma for a few hours in order to recover. I hope you aren’t expecting voluminous posting today…my exhausted brain needs to reboot, I think.

I don’t know how Dawkins does it. He’s just come off of a trip to Michigan, and will be in Oklahoma tomorrow. He is clearly made of tougher stuff than I am.

A brief moment in the magnificent history of mankind

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Isn’t that beautiful? It’s an ancient footprint in some lumpy rocks in Kenya…but it is 1½ million years old. It comes from the Koobi Fora formation, familiar to anyone who follows human evolution, and is probably from Homo ergaster. There aren’t a lot of them; one series of three hominin trails containing 2-7 prints, and a stratigraphically separate section with one trail of 2 prints and an isolated single print. But there they are, a preserved record of a trivial event — a few of our remote relatives taking a walk across a mudflat by a river — rendered awesome by their rarity and the magnitude of the time separating us.

Here’s one of the trails:

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Tessellated swath of optical laser scans of the main footprint trail on the upper footprint surface at FwJj14E. Color is rendered with 5-mm isopleths.

It’s an interesting bridge across time. There they were, a couple of pre-humans out for a stroll, perhaps on their way to find something for lunch, or strolling off to urinate, probably nothing dramatic, and these few footprints were left in drying mud to be found over a million years later, when they would be scanned with a laser, digitized, and analyzed with sophisticated software, and then uploaded to a digital network where everyone in the world can take a look at them. Something so ephemeral can be translated across incomprehensible ages…I don’t know about you, but I’m wondering about the possible future fate of the debris of my life that has ended up in landfills, or the other small smudges across the landscape that I’ve left behind me.

And what have we learned? The analysis has looked at the shape of the foot, the angle of the big toe, the distribution of weight as the hominins walked across the substrate, all the anatomical and physiological details that can be possibly extracted from a few footprints.

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Optical laser scan images color-rendered with 5-mm isopleths for footprints at both FwJj14E and GaJi10. (A) Isolated left foot (FUI1) on the upper footprint surface at FwJj14E. (B) Photograph of FUI8 on the upper footprint surface at FwJj14E, showing good definition of the toe pads; the second toe is partially obscured by the third toe. (C) Second trail on the upper footprint surface at FwJj14E, showing two left feet. (D) Third trail on the upper footprint surface at FwJj14E, showing a right and a left foot. (E) Print R3 from GaJi10 (22), re-excavated and scanned as part of this investigation. (F) Partial print (FUT1-2) on the upper footprint surface at FwJj14E; the heel area has been removed by a later bovid print. (G) Print FLI1 on the lower footprint surface at FwJj14E, rendered with 5-mm alternating black and white isopleths. (H) Inverted image of the toe area of print FUT1-1 with alternating 5-mm black and white isopleths. Note the locations of the pads of the small toes and the presence of a well-defined ball beneath the hallucial metatarsophalangeal joint. The first, third, and fifth toes are marked D1, D3, and D5, respectively.

The answer is that these beings walked just like us. The tracks are noticeably different from the even older footprints of australopithecines found at Laetoli, from 3.5 million years ago. The foot shape and the stride of Homo ergaster was statistically indistinguishable from those of modern humans, even though we know from the bones associated with these species that they were cranially distinct from us. This is not a surprise; it’s been known for a long time that we evolved these bipedal forms long ago, and that the cerebral innovations we regard as so characteristic of humanity are a relative late-comer in our history.

Remember, though, these are 1½ million years old, 250 times older than the age of the earth, according to creationists. That’s a lot of wonder and history and evidence to throw away, but they do it anyway.

Bennet MR, Harris JWK, Richmond BG, Braun DR, Mbua E, Kiura P, Olago D, Kibunjia M, Omuombo C, Behrensmeyer AK, Huddart D, Gonzalez S (2009) Early Hominin Foot Morphology Based on 1.5-Million-Year-Old Footprints from Ileret, Kenya. Science 323(5918):1197-1201.

Exposing the intimate details of the sex lives of placoderms

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The media is getting another science story wrong. I keep seeing this discovery of an array of fossil placoderms as revealing the origins of sex, and that’s not right. Sex is much, much older, and arose in single-celled organisms. Come on, plants reproduce sexually. A fish is so far removed from the time of origin of sexual reproduction that it can’t tell us much about its origins.

Let’s get it right. These fossils tells us about the origin of fu…uh, errm, mating in vertebrates.

What we have are a set of placoderm fossils from the Devonian (380 million years ago) of Western Australia (The Aussies are going to be insufferable, now that they can claim to be living in the birthplace of shagging) that show two interesting features: some contain small bits of placoderm armor that show no signs of digestion, and so are not likely to be relics of ancient cannibal feasts, but are the remains of viviparous broods — they were preggers. The other suggestive observation is that the pelvic girdle has structures resembling the claspers of modern sharks, an intromittent organ or penis used for internal fertilization.

[Read more…]

There is no one simple evolution story

I’ve never liked this stereotypical portrayal of evolution.

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It implies that evolution is linear, that it is going somewhere, and of course, that it is all about people — all the wrong messages. Yet it is ubiquitous, and probably the most common rendering you’ll find anywhere. Try googling for images of evolution, and you will turn it up, or variants on it, or jokes built on it…it’s a bit annoying and trite.

(Although, when I googled to find that image — which was easy — I also found this one.

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Very nice. I like it.)

This is actually a problem. When we’re trying to get the message of the science of evolution across to people, one thing that helps is having a story — people respond well to narratives. The canonical image definitely tells a story, which is probably why it caught the public imagination so well, but the problem is that it is the wrong story.

Evolution should not be portrayed as an epic tale with a beginning and an end, with a narrative drive to a conclusion, with a single hero or even any heroes at all. Trying to shoehorn it into a simple linear story destroys the meaning. Does this mean our efforts to catch the attention of a fickle public are doomed, because science does not fit the story-telling conventions that best fit the human mind?

Not necessarily. Here’s an interesting analogy, a comparison of the evolution story to a dramatic convention that the public does eat up happily: evolution is like a soap opera. I can see it.

Both have lots of characters and story lines, every one full of anguish and drama, some ending happily (for a while), others ending miserably; individuals come and go, they get their brief period in the spotlight, then poof, everything moves on to the next big new event. There is no one grand goal for the ensemble, just a series of overlapping dramas, some ridiculous, some mundane, and the vehicle to tie them all together is usually something commonplace — a town or a hospital, for instance — and stories can abandon that unifying premise freely. And it never ends!

Days of our Lives has been on the air since 1965. Dozens, probably hundreds, of characters have come and gone. There have been murders, affairs, rapes, and (for all I know) alien abductions. The show isn’t going anywhere. And yet as any soap-opera fan will tell you, their favorite soap has had dozens and dozens of riveting, heart-breaking stories over the years, that make the series so gratifying and rewarding in the long run.

And that’s exactly the deal with evolution. It isn’t going anywhere, and yet it’s going to keep on going and going and going for as long as there’s planet to go on, and even after that it’ll probably be going on someplace else.

Cool. And yet, somehow, all that chaos and confusion and complexity and strangely unresolvable big picture manages to engross viewers day after day after day, in the case of the soaps. There’s a lesson there that we need to figure out: how can we map the science of evolution onto the imaginations of human beings?

Francis Collins will be so disappointed

Collins has argued that one piece of evidence for god is the human moral sense, which he claims could not have evolved. I guess we’re going to have to call monkeys our brothers and sisters then, since researchers have found that monkeys have a sense of morality. (Let me guess; he’ll just push the magic moment of ensoulment back another 30 million years.) Furthermore, they have explanations for how altruism could have evolved.

Some researchers believe we could owe our consciences to climate change and, in particular, to a period of intense global warming between 50,000 and 800,000 years ago. The proto-humans living in the forests had to adapt to living on hostile open plains, where they would have been easy prey for formidable predators such as big cats.

This would have forced them to devise rules for hunting in groups and sharing food.

Christopher Boehm, director of the Jane Goodall Research Center, part of the University of Southern California’s anthropology department, believes such humans devised codes to stop bigger, stronger males hogging all the food.

“To ensure fair meat distribution, hunting bands had to gang up physically against alpha males,” he said. This theory has been borne out by studies of contemporary hunter-gatherer tribes.

In research released at the AAAS he argued that under such a system those who broke the rules would have been killed, their “amoral” genes lost to posterity. By contrast, those who abided by the rules would have had many more children.

It’s a little glib and speculative, but it’s enough to shut down the claim that morality couldn’t have evolved.

I also have deep reservations about some of the claims in the article.

Other studies have confirmed that the strength of a person’s conscience depends partly on their genes. Several researchers have shown, for example, that the children of habitual criminals will often become criminals too – even when they have had no contact with their biological parents.

Ugh. Criminality is too flexible and too easily influenced by the environment — strip me of my income and throw me on the streets, and I’ll become a criminal, too, if it keeps me and my family from going hungry. But then, I suppose anyone could claim those are just the genes of my roots in the lower socioeconomic classes.

Neandertal genome? Or a premature announcement?

In a potentially exciting development, researchers have announced the completion of a rough draft of the Neandertal genome in a talk at the AAAS, and in a press conference, and the latest issue of Science has a number of news articles on the subject. And that is a reason for having some reservations. There is no paper yet, and science by press release raises my hackles, and has done so ever since the cold fusion debacle. Not that I think this is a hoax or error by any means, but it’s not a good way to present a scientific observation.

Also, the work has some major limitations right now. They’ve got about 60% of the genome so far, and it’s all entirely from one specimen. From the age of these bones, degradation is inevitable, so there are almost certainly corrupted sequences in there — more coverage would give me much more confidence.

With those caveats, though, there are some tantalizing hints, and the subject is so exciting that it’s understandable why there’d be rush to announce. So far, they’ve identified approximately 1000-2000 amino acid differences in the coding part of the genome (human-chimp differences are about 50,000 amino acids), but there’s no report of any detectable regulatory differences.

I’m withholding judgement until I see a real paper; for now, you have to settle for a podcast with a science journalist, which just isn’t meaty enough yet.

You are not optimal

Gary Marcus, author of Kluge(amzn/b&n/abe/pwll) (a book I recommend), has an opinion piece in the Wall Street Journal that makes an important point: evolution does not produce rational, perfect, finely-tuned beings. It makes organisms that are good enough. Keep this in mind when looking at anything biological (like, say, an appendix), and it’s also true in economics, as Marcus points out — assuming that human beings will tend to make rational choices will lead to being fooled much of the time.

You are a very short note near the end of the symphony of life

Seed has compiled a short list celebratory articles and media for your Darwin Day — take a look. I rather liked The Evolution of Life in 60 Seconds: it’s very short, but it puts everything in perspective by listing key events in the 4.6 billion year history of the planet with appropriate timing to fit into one minute. If they’d put it into the context of the over 13 billion year history of the universe, it might have been even more dramatic.


Produced by Claire L. Evans.