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April 20, 2019

Gene Wolfe, death of a master

Filed under: Gene Wolfe,science fiction — Razib Khan @ 7:19 pm

Gene Wolfe, Acclaimed Science Fiction Writer, Dies at 87. Wolfe’s prose could be challenging to read. I actually read The Book of the New Sun trilogy twice because of some elements of impenetrability in the style, though there’s a reason Wolfe was acclaimed. In general, I’m not a fan of “science fantasy” or the “dying Earth” genre, but Wolfe really made it work.

One thing about Wolfe that is of interest is that like J. R. R. Tolkien he was a Catholic convert, whose religion influenced his work. Arguably more directly and consciously in the case of Wolfe. But it is subtle enough that it doesn’t distract or warrant notice. In fact, I’d argue that Severian is much less clearly a Jesus-figure than Paul in the Dune series to the naive reader.

I’m not someone who minds authors telegraphing their viewpoints and ideologies into narratives, no matter what it is. But I think there’s no point in putting it into “speculative fiction” if it’s too direct. For example, I think one reason C. S. Lewis’ Narnia cycle is less popular than Tolkien’s work is that it reads as Christian fantasy, rather than fantasy with inflections from the author’s Christian viewpoint.

Wolfe, like Tolkien, had strong personal views. But he did not let them saturate his stories. The Christian outlines and themes in The Book of the New Sun are clear after someone points them out. But they aren’t salient at all when you are reading it without foreknowledge.

September 4, 2018

Complementarity in the 21st century

Filed under: China,international relations,science fiction — Razib Khan @ 6:41 pm

The late Gordon R. Dickson wrote a series of books in a (mostly) future history termed The Childe Cycle. I’ve read a substantial number of the books in this series, and it’s rather uneven. On the whole, I would say that the earlier books are better than the later works. Dickson died before he could complete the series, but I don’t think that’s really that big of a deal, because the books are only loosely connected. I read the novels and short stories of the series all out of order, and it wasn’t a problem.

One of the interesting aspects of the universe is that there are separate human cultures/ethnicities that inhabit different planets and specialize in different economic tasks. If you look closely, the system doesn’t make economic sense, but that’s OK, we’re talking a setting for space opera.

Of the “splinter cultures,” two of them inhabit planets very close to each other in the same solar system, Newton and Cassida. Newton is home to pure scientists, while Cassida is a world of applied engineers. In Young Bleys it is stated that the engineers of Cassida admire and envy the scientists of Newton.

My point in posting about this is to a great extent I imagine that the United States of America will be the “Newton” of our world for a while longer. But, other nations will be will Cassida (you can guess which), and others the Friendlies. I don’t know who the Exotics or Dorsai might be, and the analogy might breakdown there.

June 28, 2018

Harlan Ellison, R.I.P.

Filed under: science fiction — Razib Khan @ 3:03 pm

Harlan Ellison has died.

I Have No Mouth and I Must Scream is one of the most disturbing things I have ever read. Over 20 years after reading I still remember how appalled I felt as I finished the last sentence.

Ellison was a powerful writer. Some of his innovations have become cliche (e.g., Ellison pioneered time travel plots which have now become overused). One thing I remember from Isaac Asimov’s autobiography was how much he loved Ellison for his loyalty and devotion as a friend.

With his health failing over the past few years it is not surprising he finally died. But he surely lived a very full and eventful 84 years. Ellison made a difference, and he’ll be remembered.

January 23, 2018

On the passing of Ursula K Le Guin

Filed under: science fiction,Ursula K Le Guin — Razib Khan @ 6:13 pm

About four months ago Jerry Pournelle died. He and Ursula K Le Guin did not get on, in part because of their political differences. And despite my differences with both, I read them with appreciation.

Well, Le Guin passed away today. A science fiction and fantasy great she was. I appreciate especially her defenses of “genre fiction,” since she received admiration from the literary mainstream.

That is probably because her prose was more writerly than most science fiction, which came out of the adolescent male pulp tradition, long on plot, short on a turn of the phrase.

If I had to pick a work of Le Guin’s to reread, it has to be The Tombs of Atuan. Earthsea was not a Middle Earth rip-off, and her quasi-Daoist philosophical framework was genuinely novel.

(when I lived in Berkely I would regularly pass the building named after her father)

September 8, 2017

Jerry Pournelle, 1933-2017

Filed under: Jerry Pournelle,science fiction — Razib Khan @ 4:49 pm

A few years ago I stumbled upon Fred Pohl’s weblog. Born in 1919, for a few years there before his death in 2013 Pohl was a living breathing window back to the “Golden Age” of science fiction. He knew men like Asimov and Heinlein personally. He was a witness, a participant, to history. It was great to have someone like him on the internet.

Today we lost another piece of history. This evening I learned that Jerry Pournelle passed away in his sleep. I have had a few interactions with Pournelle over the years, and it was really strange in light of the fact that I read many of his books as a child. His collaborations with Larry Niven, in particular, The Mote in God’s Eye, were always great in my opinion (each author had their own strength, and together they were better).

One thing about Pournelle’s science fiction is that their politics and sociology always struck me as unrealistic when I first encountered them. I believe in The Encyclopedia of Science Fiction he identified himself as a “13th century liberal.” As in, he was on the side of the nobles against King John. Even if tongue-in-cheek that had at the time struck me as a ridiculous claim.

But over the years I’ve come to realize that my teen years in the 1990s were excessively suffused with The End of History. Pournelle was older and had a longer view of things. I didn’t necessarily end up agreeing with Jerry Pournelle in all his views, but as I got older I began to realize that there was a lot I didn’t understand.

May 16, 2017

Tales from the Middle Cosmos

Filed under: science fiction — Razib Khan @ 4:24 pm

Over at Marginal Revolution Tyler Cowen positively mentioned an anthology of Chinese science fiction, Invisible Planets: Contemporary Chinese Science Fiction in Translation. I got a copy and I have to say it really is good (on reading only a few stories). #Recommended and #Seconded.

It is often said, correctly, that science fiction is mostly a window upon the sensibilities of the society in which it is written. In the American context this matters in relation to time. Though Isaac Asimov was a liberal on sexual matters (and frankly, a sexual harasser at conferences by even the most lax modern standards) he admitted that the fact that he came up in the “Golden Age” period when there were many taboos in regards to sex had a lifelong impact on the depiction of those matters in his fiction. In contrast writers who came up in the 70s or later didn’t have these restrictions and so did not have the same hang-ups in their fiction.

And I’ll also admit I have Amish Tripathi’s work in part because I’m curious at an Indian take on fantasy (and also because too much Western fantasy is pretty derivative).

November 4, 2012

Earthsea is Earth

Filed under: Culture,science fiction — Razib Khan @ 12:30 am

Slate has a respectful take on Ursula K. Le Guin‘s oeuvre by Choire Sicha up. By way of surveying her contributions to the domain of fiction the author takes issue with those who would elevate ‘literary fiction,’ a term whose boundaries seem to lack distinction or clarity, above ‘genre.’ In this case Le Guin’s career has been marked by extensive forays into the genres of fantasy and science fiction, and speculative fiction more broadly. But while we’re castigating the narrowness or particularity of the aficionados of literary fiction, it should be admitted that Le Guin herself does not always deny the value of parochialism.

Her Leftist politics pervades many of her works, implicitly and explicitly (just as one can not but help sense Jerry Pournelle’s conservatism in the texture of his narrative). But perhaps more subtly important for the character of her fiction Le Guin has emphasized her lack of interest in the details of the physical sciences which suffuses ‘hard science ficiton.’ Rather, her creations manipulate and tease apart filaments of the social assumptions and values we take as normative (e.g., how many other science fiction writers would admit ...

October 16, 2011

Shades of preference in storytelling

Filed under: science fiction — Razib Khan @ 12:28 am

Humans seem to have a strong bias toward narratives. We like stories. This is obvious when you read sports columns. Most of the time there’s really no substantive value-add. If you want substance, just check box scores. But we want a story. So sports columnists give us a story. Usually something mildly counter-intuitive, general platitudes and conventional wisdom with just a twist. It doesn’t matter if you’re wrong, no one cares. How many people remember Bill Walton talking about how Shawn Bradley was a better basketball player than Shaquille O’Neil?

Much the same applies to political punditry. There was no point in speculating whether Rick Perry would, or wouldn’t, do well as an aspirant nominee of the Republican party for the presidency. We’d know sooner or later. I really got tired of Texas pundits like Eric Greider going on about how we shouldn’t underestimate him. Aside from the fact that he was smart enough to be an air force officer, everything else implies that he’s not too sharp, validated especially by his recent debate performances. But we wanted a story, so there was a demand for pundits from Texas talking Perry’s prospects up. Now we have pundits like Ross Douthat echoing the line that Mitt Romney is inevitable as the nominee. Great. But remember when Ross and Matt Yglesias simply couldn’t imagine a scenario in which Hillary Clinton wasn’t the nominee in December of 2007? I do.

So we love stories. That’s a human universal. As human beings we have particular cognitive orientations which are general across our species. Our facility for language for example. An appreciation of art and other cultural productions which don’t seem to have immediate utility. But there is also variation. Our tastes differ. But sometimes we forget that. I thought of that when reading this piece in Slate, For the Love of Science Fiction. The author begins “…I disdained science fiction for many years, considering it too short on humanity and too long on pointless technical specs.“ There is definitely going to be a mention of Ursula K. Le Guin. The author concludes:

Perhaps the most important guidance Atwood offers on reading and loving science fiction is to respect the craft’s ability to explore unintended consequences but not to overstate its predictive qualities: “I carefully say a future rather than the future because the future is an unknown: from the moment now, an infinite number of roads lead away to ‘the future,’ each heading in a different direction,” she writes. I will cling to those words the next time I read a terrifying depiction of a technologically rich but morally bankrupt society in the years to come. Like the author who’s next up in my science fiction education: Neal Stephenson.

The first thing that came to mind is that the author has a background in liberal arts if they could throw out a line about “pointless technical specs.” Some people actually enjoy understanding technical specs! I mention Ursula K. Le Guin because in one of her essays she discusses her attitude toward science fiction and admitted her lack of interest in a lot of natural science, and her fascination with social science. Le Guin varies the parameters of sociology to generate her stories. In contrast, writers such as Greg Egan vary the laws of physics. Whether the former or latter is to your taste depends on your background and predispositions. In any case, the author of the above piece majored in “English with minors in business, media studies, and Latin.” If she had majored in engineering or physics I suspect that the technical sidebars and exposition which much of science fiction is larded with would seem less pointless, and much more illuminating. So this a matter of taste, not objective truth in terms of what is, and isn’t, good science fiction.

Somehow great literature is measured by psychological complexity rather than material complexity. “World building” is seen as a bonus, instead of essential context. But whether you see it as essential context or not is probably a matter of your own psychological orientation. And this exists on a continuum. Some readers of hard science fiction can not brook the fudges which are necessary in even this genre when it comes concepts such as faster-than-light travel. L. Sprague de Camp famously focused more on fantasy than hard science fiction because his background in engineering made it impossible for him to suspend disbelief even for the purpose of writing a story.

As I grow older I seem to be turning away from hard science fiction (when I have time to read fiction, which is not often). Does this mean that I am developing more refined taste? Perhaps. But I suspect that my brain is aging and changing, and so my preferences are as well. I’ve lived enough of a life that I have a requisite stock of social intelligence with which I can appreciate the subtlety in more psychologically oriented fiction, where characters have more texture and grayness. Additionally, my own technical interests in science have narrowed to the point where I get a lot less out of science fiction which is predicated on some knowledge of disciplines where my comprehension is thin. This is a case where the child is not the father of the man. Just as I have changed over time, so humans a a species have different aesthetic preferences, rather than superior and inferior ones. I wish that people would be a bit more self-aware about this.

September 26, 2011

Terra Nova half-browns

Filed under: science fiction,Television — Razib Khan @ 5:52 pm

There’s a lot buzz on the internet for a new show called Terra Nova. Didn’t we already do this? It was called Earth 2 (Steven Spielberg also had an indirect role in that show). I’m not going to watch it. I don’t have a television, and my online television watching is very circumscribed. But I did note that the family at the center of the drama is what we would call “exotic” or “ethnic” in 1980s:

Alana Mansour, the youngest actress, probably has Middle Eastern ancestry. I don’t know. But the mother is played by Shelley Conn, an Anglo-Indian. More specifically a mix of Sri Lankan and British. And the middle child, Naomi Scott, has a ethnic Indian mother from Uganda. The father and son in contrast are fully European in appearance (and Irish and white Canadian were cast for these roles), but it is not uncommon in mixed-race families for such a variance in physical types to manifest across the set of children.

July 27, 2011

The force was with him!

Filed under: science fiction,Star Wars — Razib Khan @ 9:58 am

In my post below where I focused on patent law it was noted that even more obviously blatant abuses of the spirit of intellectual property occur in copyright. So I was interested to see that George Lucas has lost a law suit in the United Kingdom in relation to the idea of “storm troopers”:

Nevertheless, the High Court rejected the multi-billionaire director’s claim and the focus switched to design rights, specifically whether the helmets sold were works of art or merely industrial props.

If Lucasfilm could convince the courts the 3D works were sculptures, they would be protected by copyright for the life of the author plus 70 years.

If not, the copyright protection would be reduced to 15 years from the date they were marketed, meaning it would have expired and Mr Ainsworth would be free to sell them.

The High Court and Court of Appeal found in Mr Ainsworth’s favour, and despite Lucas being backed by directors Steven Spielberg, James Cameron and Peter Jackson, the Supreme Court has now followed suit.

Someone on twitter quipped that Lucas should be paying royalties to the Germans for the idea of stormtroopers. But I immediately recalled that many of the ideas which set ...

September 29, 2010

A world almost built

Filed under: science fiction,Space — Razib Khan @ 3:35 pm

By now you’ve probably seen headlines such as A Habitable Exoplanet — for Real This Time. Phil Plait has a more sober assessment. Still, he concludes:

But perhaps the most interesting and exciting aspect of all this is what it implies. The Milky Way galaxy is composed of about 200 billion stars, and is 100,000 light years across. The fact that we found a planet that is even anything like the Earth at all orbiting another star only 20 light years away makes me extremely optimistic that earthlike planets are everywhere in our galaxy. 20 light years is practically in our lap compared to the vast size of our galaxy, so statistically speaking, it seems very likely it’s not unique. I don’t want to extrapolate from a data set of two (us and them), but if this is typical, there could be millions of such planets in the galaxy. Millions.

So we don’t know if this planet is all that much like Earth — the surface gravity may be quite high if it’s dense and small, for example, or it may not have any air, or it may have a thick atmosphere like Venus — but what it’s telling us is that smaller, lower mass planets at the right distance from their star for liquid water are almost certainly common in the galaxy.

I assume this means we can play around with the Drake equation? In any case, I am now reminded of Poul Anderson’s essay “The creation of imaginary worlds: the world builder’s handbook and pocket companion.” You can read most of the essay online at Google Books. Or, find it in Writing Science Fiction & Fantasy. For us “squishy science” lovers the biochemist Hal Clament has an essay which follow’s Anderson’s which outlines how to create imaginary life.

June 29, 2010

Nazis in space

Filed under: Films,Movies,science fiction — Razib Khan @ 11:19 am

Really interesting trailer for a movie which is premised on a “secret history” where a group of Nazis flee to the far side of the moon at the end of World War II, and are returning imminently in the near future from their exile.

Wired has the back story of how this group of film makers generated broad-based funding for their project. Of course they’re Finnish….

May 13, 2010

Why science fiction matters for people who don’t read science fiction

Filed under: Ray Bradbury,science fiction — Razib Khan @ 3:39 pm

Mythologist of Our Age: Why Ray Bradbury’s stories have seeped into the culture:

Science fiction dates as quickly as any genre, and Bradbury is not entirely immune to this. The futuristic rocket ships he wrote about in 1950 look a lot like the first-generation NASA rockets; the music of the future is Rachmaninoff and Duke Ellington; and in the terrifying “Mars is Heaven,” the planet bears an eerie resemblance to Green Bluff, Ill., right down to Victorian houses “covered with scrolls and rococo.” But the reason Bradbury’s stories still sing on the page is that, despite all his humanoid robots, automated houses, and rocket men, his interest is not in future technologies but in people as they live now—and how the proliferation of convenient technology alters the way we think and the way we treat each other.

savionoOne of the aspects of science fiction as a genre is that the masters of the field when viewed from outside of the core science fiction reading audience are often not necessarily dominant within the subculture. The core science fiction readership, those who immerse themselves in the genre, and might actually show up at a science fiction convention, are not the typical casual readers who might pick something up at the airport bookstore. They’re disproportionately male, disproportionately virgin, disproportionately young, and disproportionately nerdy, with a strong technical bent. For a quantitative overview of the reality of the demographic assertions I’m making, I point you to William Sims Bainbridge’s Dimensions of Science Fiction. For a more impressionistic “insider” view, you might check out Isaac Asimov’s memoirs. For examples of the “literature” which confirm that the audience for science fiction is really peculiar, I point you to Hal Clement’s oeuvre. His stories and novels would simply be unpublishable outside of the confines of the genre, they’re difficult to read for the typical person. Certainly there is action-packed space opera galore, socially conscious works of Ursula K. Le Guin, and authors who can be called literary stylists, such as Gene Wolfe. But these are in some ways deviations from type (notably, Le Guin and Wolfe are more fantasists than science fiction authors).

The heart of science fiction as a genre is “hard science fiction,” the other variants are to a great extent dilutions or modifications on the elements which you find within hard sf, with its outward focus on space, future orientation, and its embeddedness in a world where engineering is paramount. It is also notable that authors who become prominent outside of science fiction are not necessarily thought of as science fiction authors once they’ve achieved mainstream success. Sometimes this is due to the author’s own wishes, case in point being Kurt Vonnegut, who in his early years published in genre pulp magazines before becoming a literary sensation. Vonnegut pulled off the equivalent of going from working in porn to being a mainstream actor.

This weirdness of science fiction is due, I think, to the psychological diversity of mankind. Socially awkward teenage men with minimal interpersonal skills and no sexual experience with the opposite or same sex, but great fluency in the language of technology and science, are going to produce fiction which reflects their experiences, priorities and biases. They will consume fiction which reflects their experiences, priorities and biases. One reason that science fiction has traditionally been weak on character development is that many of the writers and readers are themselves tone deaf to the textured reality of most human social experiences (reading Isaac Asimov’s memoirs it seems clear that many of the early science fiction writers and fans were nerdy types who lacked social skills but made up for it with their raw intelligence).

All this makes it comprehensible why Ray Bradbury’s work has seeped into our culture; his works are only superficially science fiction. They have the exterior of science fiction, but at their heart they speak to the typical man on the street, not the nerds who form the genre’s core. Bradbury shrugged off his technical blunders without much self-consciousness. His errors were so numerous and blatant that fans, editors and critics such as Damon Knight took to mocking him in print. This is not to say that most science fiction is very technically coherent or thought out. Obviously it isn’t, else the authors wouldn’t be writers, they’d be NASA engineers designing FTL space ships. But Bradbury’s errors were often embarrassing howlers which went beyond the pale. But that’s fine for the general public, their focus would be on Bradbury’s abilities to write compelling characters and weave narrative which speaks to non-scientific issues. Which is why Ray Bradbury matters to the general public, and Larry Niven does not, and someone who considers themself a “crunchy conservative” and traditionalist Christian was intrigued by the possibilities in his fiction. Reality check: if someone who is enamored with St. Benedict and the Church Fathers thinks your literature might speak to him, you probably aren’t producing very good science fiction (as opposed to fiction).

Note: I’m focusing here on people who have read science fiction in book form. Not people who like Star Trek films. Science fiction films are generally space opera for obvious reasons, and some such as Star Wars really have more fantasy than science fiction elements (though there is good evidence that Star Wars took many of its ideas from 1930s space opera, especially E. E. Smith’s stories).

Image Credit: IMDB

April 29, 2010

Modeling the probabilities of extinction

Change is quite in the air today, whether it be climate change or human induced habitat shifts. What’s a species in the wild to do? Biologists naturally worry about loss of biodiversity a great deal, and many non-biologist humans rather high up on Maslow’s hierarchy of needs also care. And yet species loss, or the threat of extinction, seems too often to impinge upon public consciousness in a coarse categorical sense. For example the EPA classifications such as “threatened” or “endangered.” There are also vague general warnings or forebodings; warmer temperatures leading to mass extinctions as species can not track their optimal ecology and the like. And these warnings seem to err on the side of caution, as if populations of organisms are incapable of adapting, and all species are as particular as the panda.

That’s why I pointed to a recent paper in PLoS Biology, Adaptation, Plasticity, and Extinction in a Changing Environment: Towards a Predictive Theory below. I am somewhat familiar with one of the authors, Russell Lande, and his work in quantitative and ecological genetics, as well as population biology. I was also happy to note that the formal model here is rather spare, perhaps a nod to the lack of current abstraction in this particular area. Why start complex when you can start simple? Here’s their abstract:

Many species are experiencing sustained environmental change mainly due to human activities. The unusual rate and extent of anthropogenic alterations of the environment may exceed the capacity of developmental, genetic, and demographic mechanisms that populations have evolved to deal with environmental change. To begin to understand the limits to population persistence, we present a simple evolutionary model for the critical rate of environmental change beyond which a population must decline and go extinct. We use this model to highlight the major determinants of extinction risk in a changing environment, and identify research needs for improved predictions based on projected changes in environmental variables. Two key parameters relating the environment to population biology have not yet received sufficient attention. Phenotypic plasticity, the direct influence of environment on the development of individual phenotypes, is increasingly considered an important component of phenotypic change in the wild and should be incorporated in models of population persistence. Environmental sensitivity of selection, the change in the optimum phenotype with the environment, still crucially needs empirical assessment. We use environmental tolerance curves and other examples of ecological and evolutionary responses to climate change to illustrate how these mechanistic approaches can be developed for predictive purposes.

Their model here seems to be at counterpoint to something called “niche modelling” (yes, I am not on “home territory” here!), which operates under the assumption of species being optimized for a particular set of abiotic parameters, and focusing on the shifts of those parameters over space and time. So extinction risk may be predicted from a shift in climate and decrease or disappearance of potential habitat. The authors of this paper observe naturally that biological organisms are not quite so static, they exhibit both plasticity and adaptiveness within their own particular life history, as well as ability to evolve on a population wide level over time. If genetic evolution is thought of as a hill climbing algorithm I suppose a niche model presumes that the hill moves while the principal sits pat. This static vision of the tree of life seems at odds with development, behavior and evolution. The authors of this paper believe that a different formulation may be fruitful, and I am inclined to agree with them.

journal.pbio.1000357.e001As I observed above the formalism undergirding this paper is exceedingly simple. On the left-hand side you have the variable which determines the risk, or lack of risk, of extinction more or less, because it defines the maximum rate of environmental change where the population can be expected to persist. This makes intuitive sense, as extremely volatile environments would be difficult for species and individual organisms to track.Too much variation over a short period of time, and no species can bend with the winds of change rapidly enough. Here are the list of parameters in the formalism (taken from box 1 of the paper):

ηc – critical rate of environmental change: maximum rate of change which allows persistence of a population

B – environmental sensitivity of selection: change in the optimum phenotype with the environment. It’s a slope, so 0 means that the change in environment doesn’t change optimum phenotype, while a very high slope indicates a rapid shift of optimum. One presumes this is proportional to the power of natural selection

T – generation time: average age of parents of a cohort of newborn individuals. Big T means long generation times, small T means short ones

σ2 – phenotypic variance

h2 – heritability: the proportion of phenotypic variance in a trait due to additive genetic effects

rmax intrinsic rate of increase: population growth rate in the absence of constraints

b – phenotypic plasticity: influence of the environment on individual phenotypes through development. Height is plastic; compare North Koreans vs. South Koreans

γ – stabilizing selection: this is basically selection pushing in from both directions away from the phenotypic optimum. The stronger the selection, the sharper the fitness gradient. Height exhibits some shallow stabilizing dynamics; the very tall and very short seem to be less fit

Examining the equation, and knowing the parameters, some relations which we comprehend intuitively become clear. The larger the denominator, the lower the rate of maximum environmental change which would allow for population persistence, so the higher the probability of extinction. Species with large T, long generation times, are at greater risk. Scenarios where the the environmental sensitivity to selection, B, is much greater than the ability of an organism to track its environment through phenotypic plasticity, b, increase the probability of extinction. Obviously selection takes some time to operate, assuming you have extant genetic variation, so if a sharp shift in environment with radical fitness implications occurs, and the species is unable to track this in any way, population size is going to crash and extinction may become imminent.

On the numerator you see that the more heritable variation you have, the higher ηc. The rate of adaptation is proportional to the amount of heritable phenotypic variation extant within the population, because selection needs variance away from the old optimum toward the new one to shift the population central tendency. In other words if selection doesn’t result in a change in the next generation because the trait isn’t passed on through genes, then that precludes the population being able to shift its median phenotype (though presumably if there is stochastic phenotypic variation from generation to generation it would be able to persist if enough individuals fell within the optimum range). The strength of stabilizing selection and rate of natural increase also weight in favor of population persistence. I presume in the former case it has to do with the efficacy of selection in shifting the phenotypic mean (i.e., it’s like heritability), while in the latter it seems that the ability to bounce back from population crashes would redound to a species’ benefit in scenarios of environmental volatility (selection may cause a great number of deaths per generation until a new equilibrium is attained).

journal.pbio.1000357.e002Of course a model like the one above has many approximations so as to approach a level of analytical tractability. They do address some of the interdependencies of the parameters, in particular the trade-offs of phenotypic plasticity. In this equation 1/ω2b quantifies the cost of plasticity, r0 represents increase without any cost of plasticity. We’re basically talking about the “Jack-of-all-trades is a master of none” issue here. In a way this crops up when we’re talking of clonal vs. sexual lineages on an evolutionary genetic scale. The general line of thinking is that sexual lineages are at a short-term disadvantage because they’re less optimized for the environment, but when there’s a shift in the environment (or pathogen character) the clonal lineages are at much more risk because they don’t have much variation with which natural selection can work. What was once a sharper phenotypic optimum turns into a narrow and unscalable gully.

Figure 2 illustrates some of the implications of particular parameters in relation to trade-offs:


There’s a lot of explanatory text, as they cite various literature which may, or may not, support their model. Clearly the presentation here is aimed toward goading people into testing their formalism, and to see if it has any utility. I know that those who cherish biodiversity would prefer that we preserve everything (assuming we can actually record all the species), but reality will likely impose upon us particular constraints, and trade-offs. In a cost vs. benefit calculus this sort model may be useful. Which species are likely to be able to track the environmental changes to some extent? Which species are unlikely to be able to track the changes? What are the probabilities? And so forth.

I’ll let the authors conclude:

Our aim was to describe an approach based on evolutionary and demographic mechanisms that can be used to make predictions on population persistence in a changing environment and to highlight the most important variables to measure. While this approach is obviously more costly and time-consuming than niche modelling, its results are also likely to be more useful for specific purposes because it explicitly incorporates the factors that limit population response to environmental change.

The feasibility of such a mechanistic approach has been demonstrated by a few recent studies. Deutsch et al…used thermal tolerance curves to predict the fitness consequence of climate change for many species of terrestrial insects across latitudes, but without explicitly considering phenotypic plasticity or genetic evolution. Kearney et al…combined biophysical models of energy transfers with measures of heritability of egg desiccation to predict how climate change would affect the distribution of the mosquito Aedes aegiptii in Australia. Egg desiccation was treated as a threshold trait, but the possibility of phenotypic plasticity or evolution of the threshold was not considered. These encouraging efforts call for more empirical studies where genetic evolution and phenotypic plasticity are combined with demography to make predictions about population persistence in a changing environment. The simple approach we have outlined is a necessary step towards a more specific and comprehensive understanding of the influence of environmental change on population extinction.

Citation: Chevin L-M, Lande R, & Mace GM (2010). Adaptation, Plasticity, and Extinction in a Changing Environment: Towards a Predictive Theory PLoS Biol : 10.1371/journal.pbio.1000357

March 29, 2010

Hari Seldon and the liberal punditocracy

Filed under: Culture,Isaac Asimov,Pundits,science fiction — Razib Khan @ 11:59 am

Matt Yglesias muses on the possible influence of Isaac Asimove’s Foundation series on the way he looks at the world. Interestingly, Paul Krugman admits his debt to this series as well in getting him interested in economics. Unlike Robert Heinlein or mentor John W. Campbell Asimov was a political liberal. It is not uncommon for nerdy males, who are disproportionately represented in the pundit-class, to go through a science fiction phase in their youth. It would be interesting to see how interests in various authors tracked their current political positioning (I’d bet money that Poul Anderson is more popular with people who work at the Cato Institute).

Note: William Sims Bainbridge’s Dimensions of Science Fiction explores the various demographic trends which characterize the science fiction subculture. Politically there’s a bimodal distribution between liberals and libertarians, with more traditional conservatives such as Jerry Pournelle being the exception.

November 12, 2009

Avatar & the death of “Star Trek aliens”

Filed under: science fiction — Razib @ 2:52 pm

Since readers of this weblog tend toward nerdishness I’m assuming they’re following the buzz around Avatar: The Movie. I only got interested in it last night trying to figure out the references in yesterday’s South Park episode, Dances with Smurfs. Check out the tailer below. Obviously actors in regular films aren’t going to be replaced by CGI in the next few years, but, looks like we’re on the cusp of a the shift when it comes to a human being necessary to portray humanoid aliens. The “uncanny valley” is to some extent an upside in sci-fi, excluding the problems that will generate when it comes to the sticky issue of hybridization.

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