The Comedy of the Trojans

Evidence from the domestication of apple for the maintenance of autumn colours by coevolution Some insect pests avoid trees whose leaves turn red in autumn and do poorly on those trees, but can trees "lie" or is there an unbreakable link between red color and poor quality as a host, perhaps because "aphids grow better on trees that drop their leaves later [because they have enough nitrogen they can risk losing high-N leaves in frost?], which are known to have fewer autumn colours [because, by the time they lose chlorophyll, UV levels are too low to require the protection provided by red anthocyanins?]."?

Functional morphology of the ankle and the likelihood of climbing in early hominins Modern chimps use their ankles, when climbing trees, in ways some early hominins (1-4 million years ago) probably couldn't, based on fossils.

Cooperation and virulence of clinical Pseudomonas aeruginosa populations
Patients with pneumonia are sicker when bacterial cells cooperate by producing individually costly virulence factors, but bacterial populations evolved "cheaters" that don't make these factors within 9 days.

In "Rhizobitoxine producers gain more poly-3-hydroxybutyrate in symbiosis than do competing rhizobia, but reduce plant growth", published online in The ISME Journal, my PhD student Will Ratcliff describes experiments showing how symbiotic nitrogen-fixing bacteria can manipulate their plant hosts.

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"A struggle for existence inevitably follows from the high rate at which all organic beings tend to increase... It is the doctrine of Malthus applied with manifold force to the whole animal and vegetable kingdoms" -- Charles Darwin, Chapter 3, The Origin of Species

Continue reading "Oestrus Island" »

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This would combine the benefits of old-age insurance, mutual funds, and Russian roulette

The problem: even if average retirement savings were adequate, a few long-lived individuals would outlive their savings.

Insurance seems a logical solution, at first, because only a few people will live much longer than average. Insurance works well to spread current risks, such as home fires, where it’s easy to audit reserves, payouts, etc. But it’s hard to audit a promise that benefits will be available decades in the future, especially if governments are more concerned with the next election than with oversight. So pension programs (essentially old-age insurance) turn into pyramid schemes, which may fall apart as more people start collecting benefits. Government pension programs can keep making payments by raising taxes or by printing money. However, either “solution� can hurt the overall economy, e.g., by increasing inflation.

Mutual funds with stocks and bonds have the potential to keep ahead of inflation. But to supply enough income indefinitely, you need to invest a lot more money than if you were able to use it up during your lifetime. The problem, of course, is that you don’t know how long you’ll live.

Continue reading "Mutually-assured-destruction fund" »

Posted by R. Ford Denison at 9:42 AM | Permalink | Comments (0)

"What is common to the greatest number gets the least amount of care. Men pay most attention to what is their own; they care less for what is common; or at any rate they care for it only to the extent to which each is individually concerned. Even when there is no other cause for inattention, men are more prone to neglect their duty when they think that another is attending to it."

Posted by R. Ford Denison at 11:49 AM | Permalink | Comments (0)

Bruce Schneier suggests that incompatibility among communication systems used by emergency workers is the result of a tragedy of the commons. He calls it a "collective action problem."

Although there may be subtle differences, "tragedy of the commons", "collective action problem", "prisoners' dilemma", "coordination problem", and the "free-rider problem" all seem similar enough that a solution to any of them would be at least a partial solution to all of them. It's a shame that researchers working on similar problems can't all agree to use the same terminology, to facilitate communication among disciplines. But the first brave researchers to switch to the common terminology would find their papers dropping into obscurity within their own disciplines, where decisions about grants and promotions are made...

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The theme of the latest issue of Current Biology is "Biology of Societies." There are reviews on the social life of spiders, crows, hyenas, amoebae, and insects, plus the role of cognition in social interactions among humans. If you are interested in the evolution of cooperation, it might be worth a trip to your nearest university library (if you don't have access via the web) to browse this issue.

I particularly liked "Evolutionary Explanations for Cooperation" by Stuart West, Ashleigh Griffin, and Andy Gardner. Their review reprints figures from several recent papers, so you can see some of the data upon which their generalizations are based. I won't try to summarize the whole thing, just some points that may have been neglected in other reviews of this topic.

Continue reading "Evolution of cooperation reviewed" »

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Any hypothesis worthy of the name makes predictions. Testing these predictions may take a long time or lots of money. Edmond Halley's 1716 prediction that a transit of Venus could be used to measure the distance to the sun could not be tested until the next transits of Venus in 1761 and 1769, and required global scientific expeditions. (Mark your calendars for 6 June 2012!) The Rothamsted Experiment Station has been testing the hypothesis that wheat can be grown with only inorganic inputs and without rotating to other crops, since 1843. This may not be long enough to uncover all possible problems with inorganic fertilizers and continuous monoculture, but it's quite a contrast with an acquaintance who wrote that "I've been farming sustainably for three years."

If even one of a hypothesis's predictions turns out to be unambiguously wrong, the hypothesis must be discarded or revised. On the other hand, multiple correct predictions do not prove that a hypothesis is true -- there might be other hypotheses that make the same predictions. Either way, it's useful to consider several hypotheses, if you can. Tom Kinraide and I discussed these points in an article in American Biology Teacher in 2003. His boss wouldn't let him include his USDA affiliation, because someone at the lab complained that testing hypotheses would undermine his religion. I don't know; maybe it would.

In interpreting the data in this week's paper, we need to remember that conflicting hypotheses can sometimes make some of the same predictions, a point which is also reinforced in a recent review article. Both papers consider the benefits of biological diversity.

Continue reading "Diversity, stability, productivity, and policing" »

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That's what David Brin thinks is our "most urgent scientific and technical need" according to an interview in Wired Science. He doesn't go into a lot of detail, but neither do the many strangely hostile comments.

Continue reading "Better methods for pragmatic problem-solving?" »

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Politics is dominated by special interest groups that make large campaign contributions. A presidential campaign in the US can cost over one billion dollars. That's only $3 per American, so you might think that a $10 contribution from each family to their favorite candidate would make special-interest money irrelevant. Wrong!

Continue reading "Political applications of social escrow" »

Posted by R. Ford Denison at 10:00 AM | Permalink | Comments (2)

According to Hardin's paper, individuals, each pursuing self-interest, will often act in ways that undermine our collective welfare, causing problems like collapse of fish stocks or human overpopulation. He thought the solutions were essentially political, "mutual coercion, mutually agreed upon." He had little faith in technical solutions.

Mutual coercion seems to work to limit some kinds of antisocial behavior (e.g., violent crime) in many societies, but the only societies that coerce people into having fewer children (e.g., China), or more children, for that matter, -- Rumania in the 1980's is one of the more extreme examples -- can't claim that the coercion is mutually agreed upon. Furthermore, some kinds of antisocial behavior are so difficult to monitor that coercion might not be practical even if it were widely supported by the public.

Technical solutions to these sorts of problems, based on viruses that alter human behavior (e..g. a virus for altruism) or reduce human fertility have been proposed in science fiction.

Could this actually happen? This question really has two parts:

Continue reading "Viruses as technical solutions: just science fiction?" »

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Apparently some of what I wrote last week is wrong. I contacted Dr. Martin Treiber, a traffic expert in Germany who is working on an "adaptive cruise control (ACC) system that is designed not only to provide a comfortable acceleration and deceleration behaviour to the driver, but also to improve the overall traffic flow." He writes that there is sometimes a conflict between the two objectives of: 1) improving the experience of individual drivers and 2) overall traffic flow. Apparently the driving pattern that optimizes traffic flow feels unnatural to the driver.

Continue reading "Driver behavior a tragedy of the commons after all?" »

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We know that one selfish driver can slow everyone down by weaving in and out of traffic, but is the reverse also true? William Beaty claims to have figured out how one driver can eliminate those annoying, slow moving "clots" of cars. He simply maintains a longer-than-usual following distance when he approaches a clot. That prevents the clot from growing at the rear, while it gradually evaporates at the front. I would have thought that might lead to another clot behind him, but he says actual road tests show it improves traffic flow both in front and behind. Apparently the key is driving at a constant rate, which would be impossible if he were tail-gating the clot, but isn't that hard to do if you leave enough space in front of you to buffer speed fluctuations of the car ahead.

Continue reading "Tail-gating tragedy reversed?" »

Posted by R. Ford Denison at 9:38 AM | Permalink | Comments (0)

[Yossarian:] "We won't lose. We've got more men, more money, and more material. There are ten million men in uniform who could replace me. Some people are getting killed and a lot more are making money and having fun. Let somebody else get killed."
[Major Major:] "But suppose everybody on our side felt that way?"
[Yossarian:] "Then I'd certainly be a damned fool to feel any other way. Wouldn’t I?"
-- Catch-22

“In fact, four men such as they were - four men devoted to one another, from their purses to their lives; four men always supporting one another, never yielding, executing singly or together the resolutions formed in common; four arms threatening the four cardinal points, or turning toward a single point - must inevitably, either subterraneously, in open day, by mining, in the trench, by cunning, or by force, open themselves a way toward the object they wished to attain, however well it might be defended, or however distant it may seem. The only thing that astonished D'Artagnan was that his friends had never thought of this.�
-- The Three Musketeers

I suggest that the key words in these contrasting views of cooperation are “ten million� and “four.� One person in ten million deserting won’t change the course of a war, but if one swordsman in a group of four consistently puts his own safety ahead of the success of the group, the group is more likely to lose a fight, with severe consequences for everyone in the group.

Continue reading "The Tragedy of the Commons vs. The Three Musketeers" »

Posted by R. Ford Denison at 7:19 PM | Permalink | Comments (2)

Apparently the University of Minnesota is staging a controversial comedy, The Pope and the Witch, which includes a reference to condom use (not necessarily the Trojan brand) for birth control. I hadn't heard of this play, by Nobel-prize-winner Dario Fo, when I chose a name for my blog. I just thought Comedy of the Trojans sounded like it should be the opposite of Tragedy of the Commons, although it did occur to me that someone could conceivably write a play with either title. Given the emphasis in Hardin's essay on the need to reduce birth rates, I guess I should go see the play.

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How should we pay for projects or infrastructure, such as light houses or public radio, whose costs can't be charged to individual users? (Free-market enthusiasts may favor coin-operated light-houses, but even if you hire someone to drop in a coin when your ship is scheduled to arrive, you may inadvertently protect some business competitor passing by at the same time.) Assume that the general public (by which I mean the major campaign contributors that effectively control the government; more on this in a later post) is unwilling to fully fund the project through taxes.

For example, suppose there are ten thousand people who really want the local public radio station to buy a new $500,000 transmitter. Each is willing, in principle, to pay the $50 apiece it would cost. But no one is willing to donate unless sure that enough others will also donate for the transmitter to actually get built. What to do?

Continue reading "Social Escrow" »

Posted by R. Ford Denison at 10:52 AM | Permalink | Comments (0)