Inkwell: Authors and Artists
Linda Castellani (castle) Wed 26 Jun 02 11:03
Our next guest is William Calvin. Bill first joined the WELL in 1986 and recalls the early office parties when the VAX arrived. Of his research interests, he says, "I talk a lot about ape-to-human evolution and all those abrupt climate changes along the way. But mostly I try to extend Darwin's intellectual revolution to brain mechanisms. What sort of Darwinian brain wiring allows us, in just a split second, to shape up a better thought?" He is a theoretical neurobiologist, Affiliate Professor of Psychiatry and Behavioral Sciences at the University of Washington in Seattle. He's the author of 11 books, mostly for general readers, about brains and evolution including The Throwing Madonna, The Cerebral Symphony, The River That Runs Uphill, The Cerebral Code, Conversations with Neil's Brain (with George Ojemann), and How Brains Think. His book with Derek Bickerton, Lingua ex Machina: Reconciling Darwin and Chomsky with the Human Brain, is about syntax. Bill's latest book, A BRAIN FOR ALL SEASONS: Human Evolution and Abrupt Climate Change, is about what sudden climate flips did to human evolution over the last 2.5 million years. It was selected as the Scientific American Book of the Month. Here's what the July issue of Scientific American has to say, in part: " Imagine going to the first meeting of a course you'd long waited to enroll in. You sit down at your computer, open an e-mail message from your professor, in this case the author William H. Calvin and get your first lesson. Your professor is thousands of miles away. In fact, he's at 51.4N, 0.1E. Where? Why, Charles Darwin's home in Kent, England, of course, the famous Down House. "So begins Calvin's journey through evolution, particularly human evolution, as he leads his 'class' from the home of the man many would call the father of evolution to various locales that provide fodder for his ultimate message: human evolution, like that of other organisms, is not a gradual transformation of form and behavior over time. Rather, like the shifts in the environments in which organisms find themselves, evolutionary change is abrupt, even catastrophic...." Leading the discussion is Andrew Alden, who has been host of the Well's quake conference for 10 years, where he tries to raise awareness of the risks as well as the benefits of living on Earth. Andrew combines a bachelor's degree in Earth Science from the University of New Hampshire with experience in print and electronic journalism. He has participated in research with the U.S. Geological Survey in California and the waters off Alaska. Andrew has also been the Geology Guide for About.com since its inception in early 1997 (see <http://geology.about.com>.). His site has more than 100 of his articles on the Earth sciences, plus hundreds of links. All are related, in one way or another, to spreading the geologist's "long now" perspective to the public at large in light of Stewart Brand's admonition that "we are as gods and might as well get good at it." There he has had a long-standing link to Bill Calvin's site: "[Calvin] gives life to Darwin's exclamation that with evolution, 'how far more interesting, I speak from experience, will the study of natural history become!'" Please join me in welcoming Bill and Andrew to inkwell.vue!
William Calvin (william-calvin) Wed 26 Jun 02 11:24
BTW, the entire book is on the web at http://WilliamCalvin.com/BrainForAllSeasons complete with color versions of many of the grayscale book illustrations. As you will see, it has the format of a seminar held via email with a traveling professor, who sends along digital photos of the fossil sites.
Andrew Alden (alden) Wed 26 Jun 02 12:37
Hi, Bill! I read "A Brain for All Seasons" in hard copy before I visited your website, and I've never said this about anything before, but the web version of your book seems like the real version, and the print version is a cold artifact in comparison. It's partly the full-color pictures on the web, of course, but the structure--that email seminar thing--comes to life online. Your material is a challenging tangle of lines of evidence, not just a progression of A to Z like you'd put in a textbook. And yet "Brain for All Seasons" presents a body of facts, theory and background that is absolutely essential for society to learn as we collectively deal with the threats of climate change. How did you adapt your mission of educating the public from the old book model to the new web model?
William Calvin (william-calvin) Wed 26 Jun 02 14:19
Well, I think that the book is still the basic model; nothing beats the portability and random access of a book. And there is a lot added by the reputation of the publisher (University of Chicago Press in this case) for selecting and improving. The email seminar is, in this case, a literary device -- though the technology and audience are ripe for really doing things that way. I've used travelogues before, as in <a href="http://williamcalvin.com/bk3/">The River That Flows Uphill</a>. And I routinely put the full text of my <a href="http://williamcalvin.com/index.html#books">books</a> on the web. What's new with<i> <a href="http://WilliamCalvin.com/BrainForAllSeasons">A Brain for All Seasons</a> </i> is only the combination. But I am indeed glad to hear that the email seminar format and the web reading of it works well together. The web log is perhaps the format that comes closest, if I were to search for another example. I've just started to experiment with a web log myself (see www.williamcalvin.com/log).
Andrew Alden (alden) Wed 26 Jun 02 20:07
It works well for the very short chapters you use. They're more like nodes, or knots in a net, than chapters. And the instant crosslinks that, more than anything else, make web text what it is mean that readers with many different interests can traverse your material in the order that suits them. And that's important in "Brain for All Seasons" because it's not a story that people will absorb all at once--it's so rich. I come to this book from the Earth science side: the parts about the climate record and the delicate balance of sea currents that keeps the planet so habitable are familiar territory. You sum them up very well, with lots or homely, everyday analogies to drive them home. It's really a first-rate summary. So I'll let other questioners sound you out about that part. What's new for me is the detail you bring to the Homo sapiens side. If I can present the book in one sentence, it's that the human race owes its character to the gantlet of climatic shocks we've gone through during our evolution. The resilience and intelligence we've gained during these severe tests--plunging into Ice Age conditions within the space of a few years, for instance--have made us a peculiar species. We're tough and smart, and the climate changes that lie before us are tests we've passed before. The question is, can we preserve our civilization as well as our species this time? Anyway, much of your material about human evolution is news for me. Maybe it's because of baseball season--with me an Oakland fan and you, presumably, rooting for Seattle during this exciting season maybe you can relate--but I enjoy how you treat the simple skills of throwing and running as crucial ingredients in our survival. For me, it makes baseball a deeper celebration of some of our most innate behaviors. It makes me love our species even more. Is this part of what you intended to say? I know it's unscientific, but scientists have feelings too.
William Calvin (william-calvin) Wed 26 Jun 02 21:41
Andrew: "The resilience and intelligence we've gained during these severe tests--plunging into Ice Age conditions within the space of a few years, for instance--have made us a peculiar species. We're tough and smart, and the climate changes that lie before us are tests we've passed before." Well, yes and no. One of the things I've learned since my 1994 <a href="http://williamcalvin.com/1990s/1994SciAmer.htm">Scientific American article </a> is that this doesn't explain the "Why us?" question. Why us, and not the other great apes? Even the bears and other omnivores got the abrupt climate change treatment. So what was it about our ancestors that made their situation different? My answer, slowly developed in the book (best seen in the <a href="http://williamcalvin.com/BrainForAllSeasons/Mara.htm">Serengeti chapter</a>, is that we got some opportunities that the other omnivores and apes didn't get, namely the grasslands boom times immediately after all the forest and brush fires set up by the abrupt cooling and drying. The grazing herds doubled and redoubled their numbers in just a few years, and that created special opportunities for a bipedal ape that had already evolved into an effective predator of large grazing animals. And besides there wasn't much else to eat for a few generations.
Andrew Alden (alden) Wed 26 Jun 02 22:19
You're talking about back in the Pliocene days, 3 to 2 million years ago, as the ice ages were starting and early hominid species were still restricted to Africa. They had moved to the plains of East Africa and stayed there quite a long time. How did these large bipedal apes--these proto-humans-- come to thrive in that lion-infested region? One clue, as you've pointed out before, was that we could throw things.
William Calvin (william-calvin) Thu 27 Jun 02 08:26
Yes, it probably started with all the climate variability between 3 and 2 million years ago. But there were 20 fast flips, up and then down a few centuries later, all through the last ice age. About every 3000 years, and sometimes more often, a flip occurred. Think flickering fluorescents: sometimes dim, sometimes bright, but fast transitions. There are a lot of temporary grasslands with each flip; after a century, a lot is replaced by brush and forest, reducing the habitat for grazing herds. I argue that it is the temporary surges in grasslands that was so important for hominids, not the average amount of grasslands. The surge gets hominids overextended, trapped in small subpopulations that then evolve more rapidly than the main population back near the equator.
Andrew Alden (alden) Thu 27 Jun 02 12:39
Is there any chance of finding fossil evidence to support this picture? Or is it an analogy with some present-day situations? Our pictures of the past are not very good when it comes to showing the year-to-year changes in local conditions. Darwin had to apologize for that 150 years ago: there was no evidence in the fossils showing how fast or how slowly a new species arises. He had to build his argument by analogy with "artificial selection," what animal and plant breeders do. It was unfortunate that he chose the word "selection," of course, because many people have a hard time avoiding the notion of a selecTOR. But anyway, we have a few good records of these rapid climate changes that have been found since Darwin's time. The most well-known are the ice cores from Greenland and Antarctica. Particularly Greenland: only in the last 10 years did we even suspect how violently the world climate system can behave.
William Calvin (william-calvin) Thu 27 Jun 02 14:35
Yes, and the Greenland records are now backed up by good records from the tropics that 1) eliminate the usual interpretation problems of unconformities, and 2) show that the abrupt changes are essentially worldwide. The fossil record problem is that there is usually a thousand years of stirring by worms and fish on the ocean floor, or by foot traffic at archaeological sites. This smoothes the record enough so that you usualloy miss seeing the abrupt flips, except for the ones like the Younger Dryas that last 1300 years. And the smoothing converts a square pulse into a V-shaped event where you can't tell how fast it really was. What you'd most like to know is the record of fire. But there are always fires. What you need to know, to verify what you suspect from analogies to El Nino fires and the like, is whether the fires are synchronous and widespread. That's going to be very difficult. But we have enough experience with fires to know what to expect from a sudden drying and high winds.
Andrew Alden (alden) Thu 27 Jun 02 16:58
Have you been following the drilling program in the great African lakes? (One good entry page is at http://sciborg.uwaterloo.ca/research_groups/african_lakes/). It seems like this would be promising for filling in some of the detail in that region. But as you say, seeing the picture as clearly as we'd like will be very hard. What research do you think is most urgently needed, in light of the upcoming climate changes we anticipate? And let me ask this: how important is it to work out the tangled, obscure story of human evolution when the real problem is dealing with the future? I mean, for me the science is always worth doing just for its own sake, but politicians and other stakeholders must ask you that.
William Calvin (william-calvin) Thu 27 Jun 02 21:58
Most urgent is basic researech on ocean and atmosphere, especially on the thresholds for 1) Gulf Stream failure in the Greenland and Labrador seas, and 2) for atmospheric reorganization. One may lead to the other, in either order I suspect, but we really need to know how far away we are, and what strategies might work for heading off or slowing down the transition. If the transition between warm-and-wet climate (like today's) and the cool-dry-windy-dusty mode took 500 years rather than 5 years, all sorts of technofix might be possible. It's those decade scale transitions (which is what the paleoclimate record is full of) that are so dangerous in a world with 6000 times more people than the preagricultural times 12,000 years ago when it last occurred.
Andrew Alden (alden) Fri 28 Jun 02 12:40
I think we've laid out the major threads in your very rich book, Bill. Let's have some comments and questions from other readers. You told me in email that your number-1 laptop is down, so take your time...
Bob 'rab' Bickford (rab) Fri 28 Jun 02 12:50
Welcome back to the WELL, William! I've always enjoyed your ideas, even when I disagree, and when you came to talk at MSR recently I just couldn't resist asking you about this crazy online place.... Let's assume that the Gulf Stream _is_ in fact going to flip and further that it's too late to stop it or substantially slow it down. And let's further assume that letting billions of people starve to death from disrupted agriculture is just not an option. What can we do? Build giant orbiting mirrors to heat up selected parts of the northern Atlantic to evaporate enough water to raise the surface salinity enough to restart the cycle? Nuke a sea-level canal through Panama and hope the resultant flows are more stable? Build lots and lots of greenhouses?
Jeff Dooley (dooley) Fri 28 Jun 02 14:52
As it has worked out, I've read most of this book flying around in airplanes, and have just finished the "why melting can cause cooling" chapter. So, I'm not quite through it yet. You anticipate my big questions with your call for research into where the thresholds may lie for downwelling failures in the Greenland and Labrador seas. What is the current momentum (interest, funding) of this research these days? And what if any hypotheses are forming up about where these thresholds are, how to measure them, etc. And, is it fair to wonder whether such thresholds are themselves variable all over the place, depending more on the current system (global climate) state? forgive me if you answer these questions in the last part of the book, I'm reading furiously, I really am.
William Calvin (william-calvin) Fri 28 Jun 02 15:04
My laptop is not only down, it's out. The hard drive is bent. But I've always assumed that could happen; each time I went to Africa for the book, I hauled along a second laptop as backup, even though I was traveling with one carryon suitcase. So now the old laptop is back; gave an hour powerpoint talk with it this morning. Bob, I hope we don't have to jump in, trying lots of everything before we understand things better. I hope we will have time to get our act together. We don't know where the failure thresholds are, only that we're getting closer (and have been for 40-50 years). And as Jeff asks, the thresholds probably are themselves variable. Another thing to remember is that the proximate cause (the last straw, as it were) will likely be an El Nino or one of the other decade-scale climate oscillations. Our problem is to not drift into shooting distance of the thresholds.
Indigo Mallard (blueduck) Fri 28 Jun 02 15:32
Hi Bill - I was just reading an article in this week's Science News about heat shock protein 90 and how it suppresses gene expression. But stress results in the expression of genes that are otherwise not. And I thought about going through Florence, and how all those guys like Leonardo, and Bernolesci and Michelangelo lived in such a rough period - brawlers, and mercenaries in the streets, and apartment dwellers pouring boiling oil on attackers below. And it hit me that our modern civilization, in light of this mechanism has a reverse effect that changes, and may prevent the expression of characteristics of the kind which built our civilization long ago. Because it all depends on how one looks at what normal is. When normal is a people under stress, then the increase in Hp90 that occurs with greater ease is itself a kind of "adaptive evolution". Interesting topic - I'll have to read your book.
Andrew Alden (alden) Fri 28 Jun 02 16:17
Thanks for bringing up that article, blueduck. It jumped out at me too. That's part of the power of "Brain for All Seasons"--it makes a lot of far- flung subjects relevant in new ways. In this case, it's about a new way to trigger evolution.
Indigo Mallard (blueduck) Fri 28 Jun 02 17:47
Hmmm. Since I haven't read the book, can you capsulize what you mean by that? Or is it possible? [...about a new way to trigger evolution.]
Indigo Mallard (blueduck) Fri 28 Jun 02 17:55
And - I guess the essence of my observation - the corollary to that Hp90 article was that our current civilization is anti-evolution in biological terms. Now - does that suppression create opportunity for a greater number of unexpressed mutations to accumulate? Does this mean that in reality the "evolution" is happening "beneath the surface" while we are in a period of ease and stability, building up a reserve of unexpressed mutations? That would tend to indicate that periods of continued stress would actually result in a slower net mutation rate, because mutations would get filtered while they were still just one or two codons. Whereas, during suppressed periods, those mutations could just keep on mutating, which could raise the probability of coming up with something really new, different and interesting. What do you think?
Jeff Dooley (dooley) Fri 28 Jun 02 18:20
Just reading the "crash boom boom" chapter at http://www.williamcalvin.com/BrainForAllSeasons/Mara.htm would be a not bad introduction to the climate-change evolutionary pump hypothesis; an explanation for why our brains changed when chimps and bonobos didn't.
Andrew Alden (alden) Fri 28 Jun 02 20:33
Blueduck, one thing the book goes into is that evolution isn't really about mutations so much as variation. Mutations are errors in the DNA. They're caused by chemical insults, cosmic rays, natural radiation and probably some other things. Almost all mutations are bad, and a small lucky fraction are useful. But variation is a lot safer; it's the natural consequence of shuffling the genetic deck as a result of sexual reproduction. And when a species gets into a setting where quick, adaptive changes are important to preserve its survival, the more variation you can induce the better. This article in Science News (the article isn't online but the references are: http://www.sciencenews.org/20020622/bob10ref.asp) is about a weird mechanism that can promote variation when the organism is in stressful conditions. Another example: domestic cats. Most of the variety in cat breeds results from selecting variation. A few breeds, like the Rex and maybe the Manx, arise from mutations.
Indigo Mallard (blueduck) Sat 29 Jun 02 09:42
True. And interesting. But it seems to me worth noting that a gene suppression mechanism does create a system by which mutation errors can accumulate in unexpressed genes also. That mechanism is quite similar to the mechanism by which genes are reshuffled to create antibodies it seems to me.
Andrew Alden (alden) Sat 29 Jun 02 15:00
I see your point: Today's soft times are keeping a lot of people alive who would have died in the past. Those people, however unfit they may be for the past, may be harboring attributes that could help us in unknown conditions of the future. But nothing is selecting them today.
Indigo Mallard (blueduck) Sun 30 Jun 02 08:33
Well, it's not that simple. That is an old observation. This Hp90 mechanism is one that under normal conditions suppresses a great many genes. It is part of the basic control mechanism. So what I am getting at is that a mechanism which suppresses genes when the organism is not under heavy stress is a mechanism that allows those suppressed genes to change, perhaps dramatically without affecting the health of the organism.
William Calvin (william-calvin) Sun 30 Jun 02 16:15
That generating variation is under some environmental control is not too surprizing. The lesson of the invention of sex is that "variation is too important to be left to chance!"
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