science

Some great gross parasites

Parasitoid Wasps

From Charles Q. Choi’s “Web-manipulating wasps” (Live Science: 2 March 2011):

Although parasites harm their hosts, they don’t usually kill them, if only to keep themselves alive. Not so with parasitoids, which ultimately destroy and often consume their hosts. Parasitoid wasps, which inspired the monster in the movie “Alien,” lay their eggs inside their victims, with the offspring eventually devouring their way out. A number of the species control their host’s minds in extraordinary ways — the larvae of the wasp Hymenoepimecis argyraphaga, which infests the spider Plesiometa argyra, makes their victims spin unusual webs especially well-suited for supporting their cocoons.

From Charles Q. Choi’s “Male-killing bacteria” (Live Science: 2 March 2011):

The genus of bacteria known as Wolbachia infests a whopping 70 percent of the world’s invertebrates, and has evolved devious strategies to keep spreading. In female hosts, the germ can hitch a ride to the next generation aboard the mother’s eggs, and since males are essentially useless for the bacteria’s survival, the parasite often eliminates them to increase the rate of females born, by either killing male embryos outright or turning them into females.

From Charles Q. Choi’s “Head-bursting fungus” (Live Science: 2 March 2011):

Dead ant zombified by fungus

Credit: David P. Hughes

In a bizarre death sentence, the fungus Ophiocordyceps unilateralis turns carpenter ants into the walking dead. The fungus prefers the undersides of leaves of plants growing on the forest floor. That’s where temperature, humidity and sunlight are ideal for the fungus to grow and reproduce and infect more victims. The parasite gets the insects to die hanging upside down, and then erupts a long stalk from their heads with which it sprinkle its spores to other ants. Fossil evidence recently suggested this fungus has zombified ants for millions of years.

From Charles Q. Choi’s “Tongue-eating crustacean” (Live Science: 2 March 2011):

The crustacean Cymothoa exigua has the dubious and unsettling honor of being the only parasite known to replace an organ. It enters through the gills of the spotted rose snapper, attaching to the base of the fish’s tongue, where it drinks its blood. The bloodsucking causes the tongue to eventually wither away, at which point the crustacean attaches itself to the tongue stub, acting as the fish’s tongue from then on.

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Ray Bradbury on science fiction

From Sam Weller’s interview of Ray Bradbury in “The Art of Fiction No. 203” (The Paris Review: Spring 2010, No. 192):

Science fiction is any idea that occurs in the head and doesn’t exist yet, but soon will, and will change everything for everybody, and nothing will ever be the same again. As soon as you have an idea that changes some small part of the world you are writing science fiction. It is always the art of the possible, never the impossible.

I often use the metaphor of Perseus and the head of Medusa when I speak of science fiction. Instead of looking into the face of truth, you look over your shoulder into the bronze surface of a reflecting shield. Then you reach back with your sword and cut off the head of Medusa. Science fiction pretends to look into the future but it’s really looking at a reflection of what is already in front of us. So you have a ricochet vision, a ricochet that enables you to have fun with it, instead of being self-conscious and superintellectual. 

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Ray Bradbury on Edgar Rice Burroughs

From Sam Weller’s interview of Ray Bradbury in “The Art of Fiction No. 203” (The Paris Review: Spring 2010, No. 192):

But as it turns out—and I love to say it because it upsets everyone terribly—[Edgar Rice] Burroughs is probably the most influential writer in the entire history of the world.

INTERVIEWER Why do you think that?

BRADBURY By giving romance and adventure to a whole generation of boys, Burroughs caused them to go out and decide to become special. That’s what we have to do for everyone, give the gift of life with our books. Say to a girl or boy at age ten, Hey, life is fun! Grow tall! I’ve talked to more biochemists and more astronomers and technologists in various fields, who, when they were ten years old, fell in love with John Carter and Tarzan and decided to become something romantic. Burroughs put us on the moon. All the technologists read Burroughs. I was once at Caltech with a whole bunch of scientists and they all admitted it. Two leading astronomers—one from Cornell, the other from Caltech—came out and said, Yeah, that’s why we became astronomers. We wanted to see Mars more closely.

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William Burroughs on the necessary changes in biology

From Conrad Knickerbocker’s interview of William S. Burroughs in “The Art of Fiction No. 36” (The Paris Review: Fall 1965, No. 35):

Science eventually will be forced to establish courts of biologic mediation, because life-forms are going to become more incompatible with the conditions of existence as man penetrates further into space. Mankind will have to undergo biologic alterations ultimately, if we are to survive at all. This will require biologic law to decide what changes to make. We will simply have to use our intelligence to plan mutations, rather than letting them occur at random. Because many such mutations—look at the saber-toothed tiger—are bound to be very poor engineering designs. The future, decidedly, yes. I think there are innumerable possibilities, literally innumerable. The hope lies in the development of nonbody experience and eventually getting away from the body itself, away from three-dimensional coordinates and concomitant animal reactions of fear and flight, which lead inevitably to tribal feuds and dissension.

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How male water striders blackmail females into sex

From Ed Yong’s “Male water striders summon predators to blackmail females into having sex” (Discover: 10 August 2010):

Water strider sex begins unceremoniously: the male mounts the female without any courtship rituals or foreplay. She may resist but if she does, he starts to actively strum the water surface with his legs. Each vibration risks attracting the attention of a hungry predator, like a fish or backswimmer (above). And because the female is underneath, she will bear the brunt of any assault. By creating dangerous vibes, the male intimidates the female into submitting to his advances. Faint heart, it is said, never did win fair lady.

A male water strider doesn’t have to go through the hardships of pregnancy and he plays no role in raising the next generation. It’s a theme that echoes throughout the animal kingdom and it means that the best strategy for him is to mate with as many females as possible. After all, he has plenty of sperm to go around. A female, however, has a limited supply of eggs and mating opportunities. When she has sex, it has to count, so it suits her to be choosy. And she has the right equipment for the job.

Last year, Chang Han and Piotr Jablonski from Seoul National University found that female red-backed water striders (Gerris gracilicornis) can block their vaginas with hard genital shields. This defence is important because once the male manages to insert his penis, he can inflate it to make him harder to throw off. The female’s only hope is to prevent him from getting through in the first place.

Hyper-violent males can sometimes wear the female down but some opt for a subtler approach – they tap intricate rhythms on the water with their legs. When Han and Jablonski discovered these rituals last year, they suggested that the males might be trying to demonstrate their quality, by tapping out the most consistent rhythms. Now, they have another explanation – the tapping is a form of blackmail, a way of coercing sex from the female with the threat of death.

The duo studied the preferences of the backswimmer – a predatory bug that floats upside-down at the water’s surface and listens out for the vibrations of potential prey. When given a choice between a silent male water strider and a mating pair with a tapping male, the backswimmer always headed towards the vibrating duo. And since these predators attack from below, the female was always the one who was injured while the male strode off to tap another day.

The backswimmer menace is so potent that after a few minutes of tapping from the male, the female relents by opening her genital shield. If she had been previously attacked by predators, she gave in almost instantly. And only when she relented did the male stop his threatening taps.

The battle of the sexes between male and female water striders has led to a whole suite of adaptations and counter-adaptations. Some males have evolved special grasping structures to give them a better hold of females, while females have responded by evolving spines and other defences to weaken their grip. Females evolved their impregnable genital shields, which males have countered with a behaviour that makes females more likely to lower their defences.

To be honest, the female water strider has an easy time of it. In other insects, where females have evolved an upper hand in the war of the sexes, males have developed even more extreme counter-strategies. Look no further than the common bedbug – the male bypasses the female’s genitals altogether and stabs his sharp penis straight into the female’s back, a technique known appropriately as traumatic insemination.

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Atheism is not fundamentalism

From PZ Myers’s “High Priest Epstein in Newsweek” (Pharyngula: 14 June 2007):

The “new atheism” (I don’t like that phrase, either) is about taking a core set of principles that have proven themselves powerful and useful in the scientific world — you’ve probably noticed that many of these uppity atheists are coming out of a scientific background — and insisting that they also apply to everything else people do. These principles are a reliance on natural causes and demanding explanations in terms of the real world, with a documentary chain of evidence, that anyone can examine. The virtues are critical thinking, flexibility, openness, verification, and evidence. The sins are dogma, faith, tradition, revelation, superstition, and the supernatural. There is no holy writ, and a central idea is that everything must be open to rational, evidence-based criticism — it’s the opposite of fundamentalism.

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Girls & boys & brain chemicals

Twins #109
Creative Commons License photo credit: Oude School

From John Cloud’s “Why Girls Have BFFs and Boys Hang Out in Packs” (TIME: 17 July 2009):

For the better part of the past half-century, feminists, their opponents and armies of academics have debated the differences between men and women. Only in the past few years have scientists been able to use imaging technology to look inside men’s and women’s heads to investigate whether those stereotypical gender differences have roots in the brain. No concrete results have emerged from these studies yet, but now a new functional magnetic resonance imaging (fMRI) study of children offers at least one explanation for some common tween social behaviors: girls are hardwired to care about one-on-one relationships with their BFFs (best friends forever), while the brains of boys are more attuned to group dynamics and competition with other boys.

The study, conducted by researchers at the National Institute of Mental Health (NIMH) and Georgia State University, begins with a premise that every parent of a tween knows: as kids emerge into puberty, their focus changes dramatically. They care less about their families and more about their peers.

So what’s actually going on inside these young brains?

The results suggest that as girls progress from early puberty to late adolescence, certain regions of their brains become more active when they face a potential social interaction. Specifically, when an older girl anticipates meeting someone new — someone she believes will be interested in her — her nucleus accumbens (which is associated with reward and motivation), hypothalamus (associated with hormone secretion), hippocampus (associated with social learning) and insula (associated with subjective feelings) all become more active. By contrast, boys in the same situation show no such increase in activity in these areas. In fact, the activity in their insula actually declines.

Boys, it seems, aren’t as interested in one-on-one interactions as girls are. Previous research has shown that male adolescents instead become more focused on competition within larger groups (like between sports teams). Perhaps it’s evidence that evolution has programmed boys to compete within large groups, so they can learn to eliminate rivals for women — and that girls have been programmed to judge, one-on-one, who would be the most protective father for offspring.

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RFID security problems

Old British passport cover
Creative Commons License photo credit: sleepymyf

2005

From Brian Krebs’ “Leaving Las Vegas: So Long DefCon and Blackhat” (The Washington Post: 1 August 2005):

DefCon 13 also was notable for being the location where two new world records were set — both involved shooting certain electronic signals unprecedented distances. Los Angeles-based Flexilis set the world record for transmitting data to and from a “passive” radio frequency identification (RFID) card — covering a distance of more than 69 feet. (Active RFID — the kind being integrated into foreign passports, for example — differs from passive RFID in that it emits its own magnetic signal and can only be detected from a much shorter distance.)

The second record set this year at DefCon was pulled off by some teens from Cincinnati, who broke the world record they set last year by building a device capable of maintaining an unamplified, 11-megabit 802.11b wireless Internet connection over a distance of 125 miles (the network actually spanned from Utah into Nevada).

From Andrew Brandt’s “Black Hat, Lynn Settle with Cisco, ISS” (PC World: 29 July 2005):

Security researcher Kevin Mahaffey makes a final adjustment to a series of radio antennas; Mahaffey used the directional antennas in a demonstration during his presentation, “Long Range RFID and its Security Implications.” Mahaffey and two of his colleagues demonstrated how he could increase the “read range” of radio frequency identification (RF) tags from the typical four to six inches to approximately 50 feet. Mahaffey said the tags could be read at a longer distance, but he wanted to perform the demonstration in the room where he gave the presentation, and that was the greatest distance within the room that he could demonstrate. RFID tags such as the one Mahaffey tested will begin to appear in U.S. passports later this year or next year.

2006

From Joris Evers and Declan McCullagh’s “Researchers: E-passports pose security risk” (CNET: 5 August 2006):

At a pair of security conferences here, researchers demonstrated that passports equipped with radio frequency identification (RFID) tags can be cloned with a laptop equipped with a $200 RFID reader and a similarly inexpensive smart card writer. In addition, they suggested that RFID tags embedded in travel documents could identify U.S. passports from a distance, possibly letting terrorists use them as a trigger for explosives.

At the Black Hat conference, Lukas Grunwald, a researcher with DN-Systems in Hildesheim, Germany, demonstrated that he could copy data stored in an RFID tag from his passport and write the data to a smart card equipped with an RFID chip.

From Kim Zetter’s “Hackers Clone E-Passports” (Wired: 3 August 2006):

In a demonstration for Wired News, Grunwald placed his passport on top of an official passport-inspection RFID reader used for border control. He obtained the reader by ordering it from the maker — Walluf, Germany-based ACG Identification Technologies — but says someone could easily make their own for about $200 just by adding an antenna to a standard RFID reader.

He then launched a program that border patrol stations use to read the passports — called Golden Reader Tool and made by secunet Security Networks — and within four seconds, the data from the passport chip appeared on screen in the Golden Reader template.

Grunwald then prepared a sample blank passport page embedded with an RFID tag by placing it on the reader — which can also act as a writer — and burning in the ICAO layout, so that the basic structure of the chip matched that of an official passport.

As the final step, he used a program that he and a partner designed two years ago, called RFDump, to program the new chip with the copied information.

The result was a blank document that looks, to electronic passport readers, like the original passport.

Although he can clone the tag, Grunwald says it’s not possible, as far as he can tell, to change data on the chip, such as the name or birth date, without being detected. That’s because the passport uses cryptographic hashes to authenticate the data.

Grunwald’s technique requires a counterfeiter to have physical possession of the original passport for a time. A forger could not surreptitiously clone a passport in a traveler’s pocket or purse because of a built-in privacy feature called Basic Access Control that requires officials to unlock a passport’s RFID chip before reading it. The chip can only be unlocked with a unique key derived from the machine-readable data printed on the passport’s page.

To produce a clone, Grunwald has to program his copycat chip to answer to the key printed on the new passport. Alternatively, he can program the clone to dispense with Basic Access Control, which is an optional feature in the specification.

As planned, U.S. e-passports will contain a web of metal fiber embedded in the front cover of the documents to shield them from unauthorized readers. Though Basic Access Control would keep the chip from yielding useful information to attackers, it would still announce its presence to anyone with the right equipment. The government added the shielding after privacy activists expressed worries that a terrorist could simply point a reader at a crowd and identify foreign travelers.

In theory, with metal fibers in the front cover, nobody can sniff out the presence of an e-passport that’s closed. But [Kevin Mahaffey and John Hering of Flexilis] demonstrated in their video how even if a passport opens only half an inch — such as it might if placed in a purse or backpack — it can reveal itself to a reader at least two feet away.

In addition to cloning passport chips, Grunwald has been able to clone RFID ticket cards used by students at universities to buy cafeteria meals and add money to the balance on the cards.

He and his partners were also able to crash RFID-enabled alarm systems designed to sound when an intruder breaks a window or door to gain entry. Such systems require workers to pass an RFID card over a reader to turn the system on and off. Grunwald found that by manipulating data on the RFID chip he could crash the system, opening the way for a thief to break into the building through a window or door.

And they were able to clone and manipulate RFID tags used in hotel room key cards and corporate access cards and create a master key card to open every room in a hotel, office or other facility. He was able, for example, to clone Mifare, the most commonly used key-access system, designed by Philips Electronics. To create a master key he simply needed two or three key cards for different rooms to determine the structure of the cards. Of the 10 different types of RFID systems he examined that were being used in hotels, none used encryption.

Many of the card systems that did use encryption failed to change the default key that manufacturers program into the access card system before shipping, or they used sample keys that the manufacturer includes in instructions sent with the cards. Grunwald and his partners created a dictionary database of all the sample keys they found in such literature (much of which they found accidentally published on purchasers’ websites) to conduct what’s known as a dictionary attack. When attacking a new access card system, their RFDump program would search the list until it found the key that unlocked a card’s encryption.

“I was really surprised we were able to open about 75 percent of all the cards we collected,” he says.

2009

From Thomas Ricker’s “Video: Hacker war drives San Francisco cloning RFID passports” (Engadget: 2 February 2009):

Using a $250 Motorola RFID reader and antenna connected to his laptop, Chris recently drove around San Francisco reading RFID tags from passports, driver licenses, and other identity documents. In just 20 minutes, he found and cloned the passports of two very unaware US citizens.

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Quanta Crypto: cool but useless

From Bruce Schneier’s “Quantum Cryptography” (Crypto-Gram: 15 November 2008):

Quantum cryptography is back in the news, and the basic idea is still unbelievably cool, in theory, and nearly useless in real life.

The idea behind quantum crypto is that two people communicating using a quantum channel can be absolutely sure no one is eavesdropping. Heisenberg’s uncertainty principle requires anyone measuring a quantum system to disturb it, and that disturbance alerts legitimate users as to the eavesdropper’s presence. No disturbance, no eavesdropper — period.

While I like the science of quantum cryptography — my undergraduate degree was in physics — I don’t see any commercial value in it. I don’t believe it solves any security problem that needs solving. I don’t believe that it’s worth paying for, and I can’t imagine anyone but a few technophiles buying and deploying it. Systems that use it don’t magically become unbreakable, because the quantum part doesn’t address the weak points of the system.

Security is a chain; it’s as strong as the weakest link. Mathematical cryptography, as bad as it sometimes is, is the strongest link in most security chains. Our symmetric and public-key algorithms are pretty good, even though they’re not based on much rigorous mathematical theory. The real problems are elsewhere: computer security, network security, user interface and so on.

Cryptography is the one area of security that we can get right. We already have good encryption algorithms, good authentication algorithms and good key-agreement protocols.

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A better alternative to text CAPTCHAs

From Rich Gossweiler, Maryam Kamvar, & Shumeet Baluja’s “What’s Up CAPTCHA?: A CAPTCHA Based On Image Orientation” (Google: 20-24 April 2009):

There are several classes of images which can be successfully oriented by computers. Some objects, such as faces, cars, pedestrians, sky, grass etc.

Many images, however, are difficult for computers to orient. For example, indoor scenes have variations in lighting sources, and abstract and close-up images provide the greatest challenge to both computers and people, often because no clear anchor points or lighting sources exist.

The average performance on outdoor photographs, architecture photographs and typical tourist type photographs was significantly higher than the performance on abstract photographs, close-ups and backgrounds. When an analysis of the features used to make the discriminations was done, it was found that the edge features play a significant role.

It is important not to simply select random images for this task. There are many cues which can quickly reveal the upright orientation of an image to automated systems; these images must be filtered out. For example, if typical vacation or snapshot photos are used, automated rotation accuracies can be in the 90% range. The existence of any of the cues in the presented images will severely limit the effectiveness of the approach. Three common cues are listed below:

1. Text: Usually the predominant orientation of text in an image reveals the upright orientation of an image.

2. Faces and People: Most photographs are taken with the face(s) / people upright in the image.

3. Blue skies, green grass, and beige sand: These are all revealing clues, and are present in many travel/tourist photographs found on the web. Extending this beyond color, in general, the sky often has few texture/edges in comparison to the ground. Additional cues found important in human tests include "grass", "trees", "cars", "water" and "clouds".

Second, due to sometimes warped objects, lack of shading and lighting cues, and often unrealistic colors, cartoons also make ideal candidates. … Finally, although we did not alter the content of the image, it may be possible to simply alter the color- mapping, overall lighting curves, and hue/saturation levels to reveal images that appear unnatural but remain recognizable to people.

To normalize the shape and size of the images, we scaled each image to a 180×180 pixel square and we then applied a circular mask to remove the image corners.

We have created a system that has sufficiently high human- success rates and sufficiently low computer-success rates. When using three images, the rotational CAPTCHA system results in an 84% human success metric, and a .009% bot-success metric (assuming random guessing). These metrics are based on two variables: the number of images we require a user to rotate and the size of the acceptable error window (the degrees from upright which we still consider to be upright). Predictably, as the number of images shown becomes greater, the probability of correctly solving them decreases. However, as the error window increases, the probability of correctly solving them increases. The system which results in an 84% human success rate and .009% bot success rate asks the user to rotate three images, each within 16° of upright (8-degrees on either side of upright).

A CAPTCHA system which displayed ≥ 3 images with a ≤ 16-degree error window would achieve a guess success rate of less than 1 in 10,000, a standard acceptable computer success rates for CAPTCHAs.

In our experiments, users moved a slider to rotate the image to its upright position. On small display devices such as a mobile phone, they could directly manipulate the image using a touch screen, as seen in Figure 12, or can rotate it via button presses.

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German twins commit the perfect crime

From “Twins Suspected in Spectacular Jewelry Heist Set Free” (Spiegel Online International: 19 March 2009):

Saved by their indistinguishable DNA, identical twins suspected in a massive jewelry heist have been set free. Neither could be exclusively linked to the DNA evidence.

German police say at least one of the identical twin brothers Hassan and Abbas O. may have perpetrated a recent multimillion euro jewelry heist in Berlin. But because of their indistinguishable DNA, neither can be individually linked to the crime. Both were set free on Wednesday.

In the early morning hours of February 25, three masked men broke into Germany’s famous luxury department store Kaufhaus Des Westens (KaDeWe). Video cameras show how they climbed into the store’s grand main hall, broke open cabinets and display cases and made off with an estimated €5 million worth of jewelry and watches.

When police found traces of DNA on a glove left at the scene of the crime, it seemed that the criminals responsible for Germany’s most spectacular heist in years would be caught. But the DNA led to not one but two suspects — 27-year-old identical, or monozygotic, twins with near-identical DNA.

German law stipulates that each criminal must be individually proven guilty. The problem in the case of the O. brothers is that their twin DNA is so similar that neither can be exclusively linked to the evidence using current methods of DNA analysis. So even though both have criminal records and may have committed the heist together, Hassan and Abbas O. have been set free.

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Fossils are the lucky ones

From Errol Morris’ “Whose Father Was He? (Part Five)” (The New York Times: 2 April 2009):

I had an opportunity to visit the fossil collections at the Museum of the Rockies in Bozeman, Montana. It was part of a dinosaur fossil-hunting trip with Jack Horner, the premier hunter of T-Rex skeletons. Downstairs in the lab, there was a Triceratops skull sitting on a table. I picked it up and inserted my finger into the brain cavity. (I had read all these stories about how small the Triceratops brain had to have been and I wanted to see for myself.) I said to Jack Horner, “To think that someday somebody will do that with my skull.” And he said, “You should be so lucky. It’s only the privileged few of us who get to be fossils.”

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Why did Thomas Jefferson bring a stuffed moose to France?

From David G. Post’s “Jefferson’s Moose” (Remarks presented at the Stanford Law School Conference on Privacy in Cyberspace: 7 February 2000):

In 1787, Jefferson, then the American Minister to France, had the “complete skeleton, skin & horns of the Moose” shipped to him in Paris and mounted in the lobby of his hotel. One can only imagine the comments made by bemused onlookers and hotel staff.

This was no small undertaking at that time — I suppose it would be no small undertaking even today. It’s not as if he had no other things to do with his time or his money. It’s worth asking: Why did he do it? What could have possessed him?

He wanted, first, to shock. He wanted his French friends to stand back, to gasp, and to say: There really is a new world out there, one that has things in it that we can hardly imagine. He wanted them to have what Lessig called an “aha! moment” in regard to the New World from out of which Jefferson (and his moose) had emerged.

But there was another, more specific, purpose. He wanted to show them that this new world was not a degenerate place. The Comte de Buffon, probably the most celebrated naturalist of the late 18th Century, had propounded just such a theory about the degeneracy of life in the New World. Jefferson described Buffon’s theory this way:

“That the animals common both to the old and new world, are smaller in the latter; that those peculiar to the new, are on a smaller scale; that those which have been domesticated in both, have degenerated in America; and that on the whole the New World exhibits fewer species.”

Though it may be hard to appreciate from our more enlightened 21st century perspective, this was deadly serious stuff — both as science and, more to our point here, as politics; to Jefferson, Buffon’s theory had ominous political implications, for it was, as he put it, “within one step” of the notion that man, too, would degenerate in the New World. Thus, it could and did give a kind of intellectual cover to the notion that man in the New World could not be trusted to govern himself.

Sometimes a picture — or, better yet, a carcass — is worth a thousand words. So out comes the moose; larger than its European counterparts (the reindeer and caribou), its brooding presence in downtown Paris would surely make observers think twice about Buffon’s theory. Jefferson was no fool; he knew full well that one data point does not settle the argument, and he would provide, in his “Notes on the State of Virginia,” a detailed refutation of Buffon’s charge, page after page of careful analysis of the relative sizes of American and European animals.

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The hard truths science reveals

From Steven Weinberg’s “Without God” (The New York Review of Books: 25 September 2008):

Worse, the worldview of science is rather chilling. Not only do we not find any point to life laid out for us in nature, no objective basis for our moral principles, no correspondence between what we think is the moral law and the laws of nature, of the sort imagined by philosophers from Anaximander and Plato to Emerson. We even learn that the emotions that we most treasure, our love for our wives and husbands and children, are made possible by chemical processes in our brains that are what they are as a result of natural selection acting on chance mutations over millions of years. And yet we must not sink into nihilism or stifle our emotions. At our best we live on a knife-edge, between wishful thinking on one hand and, on the other, despair.

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4 sources of tension between science and religion

From Steven Weinberg’s “Without God” (The New York Review of Books: 25 September 2008):

But if the direct conflict between scientific knowledge and specific religious beliefs has not been so important in itself, there are at least four sources of tension between science and religion that have been important.

The first source of tension arises from the fact that religion originally gained much of its strength from the observation of mysterious phenomena – thunder, earthquakes, disease – that seemed to require the intervention of some divine being. There was a nymph in every brook, and a dryad in every tree. But as time passed more and more of these mysteries have been explained in purely natural ways. Explaining this or that about the natural world does not of course rule out religious belief. But if people believe in God because no other explanation seems possible for a whole host of mysteries, and then over the years these mysteries were one by one resolved naturalistically, then a certain weakening of belief can be expected.

Of course, not everything has been explained, nor will it ever be. The important thing is that we have not observed anything that seems to require supernatural intervention for its explanation. There are some today who cling to the remaining gaps in our understanding (such as our ignorance about the origin of life) as evidence for God. But as time passes and more and more of these gaps are filled in, their position gives an impression of people desperately holding on to outmoded opinions.

The problem for religious belief is not just that science has explained a lot of odds and ends about the world. There is a second source of tension: that these explanations have cast increasing doubt on the special role of man, as an actor created by God to play a starring part in a great cosmic drama of sin and salvation. We have had to accept that our home, the earth, is just another planet circling the sun; our sun is just one of a hundred billion stars in a galaxy that is just one of billions of visible galaxies; and it may be that the whole expanding cloud of galaxies is just a small part of a much larger multiverse, most of whose parts are utterly inhospitable to life. As Richard Feynman has said, “The theory that it’s all arranged as a stage for God to watch man’s struggle for good and evil seems inadequate.”

A third source of tension between science and religious belief has been more important in Islam than in Christianity. Around 1100, the Sufi philosopher Abu Hamid al-Ghazzali argued against the very idea of laws of nature, on the grounds that any such law would put God’s hands in chains. According to al-Ghazzali, a piece of cotton placed in a flame does not darken and smolder because of the heat of the flame, but because God wants it to darken and smolder. Laws of nature could have been reconciled with Islam, as a summary of what God usually wants to happen, but al-Ghazzali did not take that path.

Al-Ghazzali is often described as the most influential Islamic philosopher. I wish I knew enough to judge how great was the impact on Islam of his rejection of science. At any rate, science in Muslim countries, which had led the world in the ninth and tenth centuries, went into a decline in the century or two after al-Ghazzali. As a portent of this decline, in 1194 the Ulama of Córdoba burned all scientific and medical texts.

Nor has science revived in the Islamic world. … in 2002 the periodical Nature carried out a survey of science in Islamic countries, and found just three areas in which the Islamic world produced excellent science, all three directed toward applications rather than basic science. They were desalination, falconry, and camel breeding.

Something like al-Ghazzali’s concern for God’s freedom surfaced for a while in Christian Europe, but with very different results. In Paris and Canterbury in the thirteenth century there was a wave of condemnations of those teachings of Aristotle that seemed to limit the freedom of God to do things like create a vacuum or make several worlds or move the heavens in straight lines. The influence of Thomas Aquinas and Albertus Magnus saved the philosophy of Aristotle for Europe, and with it the idea of laws of nature. But although Aristotle was no longer condemned, his authority had been questioned – which was fortunate, since nothing could be built on his physics. Perhaps it was the weakening of Aristotle’s authority by reactionary churchmen that opened the door to the first small steps toward finding the true laws of nature at Paris and Lisieux and Oxford in the fourteenth century.

There is a fourth source of tension between science and religion that may be the most important of all. Traditional religions generally rely on authority, whether the authority is an infallible leader, such as a prophet or a pope or an imam, or a body of sacred writings, a Bible or a Koran. …

Of course, scientists rely on authorities, but of a very different sort. If I want to understand some fine point about the general theory of relativity, I might look up a recent paper by an expert in the field. But I would know that the expert might be wrong. One thing I probably would not do is to look up the original papers of Einstein, because today any good graduate student understands general relativity better than Einstein did. We progress. Indeed, in the form in which Einstein described his theory it is today generally regarded as only what is known in the trade as an effective field theory; that is, it is an approximation, valid for the large scales of distance for which it has been tested, but not under very cramped conditions, as in the early big bang.

We have our heroes in science, like Einstein, who was certainly the greatest physicist of the past century, but for us they are not infallible prophets.

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Intelligent Design? How about a flat earth?

From Steven Weinberg’s “Without God” (The New York Review of Books: 25 September 2008):

Contradictions between scripture and scientific knowledge have occurred again and again, and have generally been accommodated by the more enlightened among the religious. For instance, there are verses in both the Old and New Testament that seem to show that the earth is flat, and as noted by Copernicus (quoted by Galileo in the same letter to Christina) these verses led some early Church fathers like Lactantius to reject the Greek understanding that the earth is a sphere, but educated Christians long before the voyages of Columbus and Magellan had come to accept the spherical shape of the earth. Dante found the interior of the spherical earth a convenient place to store sinners.

What was briefly a serious issue in the early Church has today become a parody. The astrophysicist Adrian Melott of the University of Kansas, in a fight with zealots who wanted equal time for creationism in the Kansas public schools, founded an organization called FLAT (Families for Learning Accurate Theories). His society parodied creationists by demanding equal time for flat earth geography, arguing that children should be exposed to both sides of the controversy over the shape of the earth.

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Michael Pollan’s rules for food

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Image by rsgranne via Flickr

From John Schwenkler’s “Food for thought: renewing the culinary culture should be a conservative cause” (The American Conservative: 2008):

Michael Pollan’s In Defense of Food deconstructs the pretensions of “food science” in often hilarious fashion and distills all you need to know about eating into three directives: Eat food (as opposed to things with unfamiliar or unpronounceable ingredients, packaged “food products” that make government-sanctioned health claims, and pretty much anything from the middle aisles of the grocery store); Not too much (go for quality over quantity, and eat at a table, with others); Mostly plants (in unprocessed form when possible).

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Why we can easily remember jingles but not jokes

From Natalie Angier’s “In One Ear and Out the Other” (The New York Times: 16 March 2009):

In understanding human memory and its tics, Scott A. Small, a neurologist and memory researcher at Columbia, suggests the familiar analogy with computer memory.

We have our version of a buffer, he said, a short-term working memory of limited scope and fast turnover rate. We have our equivalent of a save button: the hippocampus, deep in the forebrain is essential for translating short-term memories into a more permanent form.

Our frontal lobes perform the find function, retrieving saved files to embellish as needed. And though scientists used to believe that short- and long-term memories were stored in different parts of the brain, they have discovered that what really distinguishes the lasting from the transient is how strongly the memory is engraved in the brain, and the thickness and complexity of the connections linking large populations of brain cells. The deeper the memory, the more readily and robustly an ensemble of like-minded neurons will fire.

This process, of memory formation by neuronal entrainment, helps explain why some of life’s offerings weasel in easily and then refuse to be spiked. Music, for example. “The brain has a strong propensity to organize information and perception in patterns, and music plays into that inclination,” said Michael Thaut, a professor of music and neuroscience at Colorado State University. “From an acoustical perspective, music is an overstructured language, which the brain invented and which the brain loves to hear.”

A simple melody with a simple rhythm and repetition can be a tremendous mnemonic device. “It would be a virtually impossible task for young children to memorize a sequence of 26 separate letters if you just gave it to them as a string of information,” Dr. Thaut said. But when the alphabet is set to the tune of the ABC song with its four melodic phrases, preschoolers can learn it with ease.

And what are the most insidious jingles or sitcom themes but cunning variations on twinkle twinkle ABC?

Really great jokes, on the other hand, punch the lights out of do re mi. They work not by conforming to pattern recognition routines but by subverting them. “Jokes work because they deal with the unexpected, starting in one direction and then veering off into another,” said Robert Provine, a professor of psychology at the University of Maryland, Baltimore County, and the author of “Laughter: A Scientific Investigation.” “What makes a joke successful are the same properties that can make it difficult to remember.”

This may also explain why the jokes we tend to remember are often the most clichéd ones. A mother-in-law joke? Yes…

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Facebook & the Dunbar number

From The Economist‘s “Primates on Facebook” (26 February 2009):

Robin Dunbar, an anthropologist who now works at Oxford University, concluded that the cognitive power of the brain limits the size of the social network that an individual of any given species can develop. Extrapolating from the brain sizes and social networks of apes, Dr Dunbar suggested that the size of the human brain allows stable networks of about 148. Rounded to 150, this has become famous as “the Dunbar number”.

Many institutions, from neolithic villages to the maniples of the Roman army, seem to be organised around the Dunbar number. Because everybody knows everybody else, such groups can run with a minimum of bureaucracy. But that does not prove Dr Dunbar’s hypothesis is correct, and other anthropologists, such as Russell Bernard and Peter Killworth, have come up with estimates of almost double the Dunbar number for the upper limit of human groups. Moreover, sociologists also distinguish between a person’s wider network, as described by the Dunbar number or something similar, and his social “core”. Peter Marsden, of Harvard University, found that Americans, even if they socialise a lot, tend to have only a handful of individuals with whom they “can discuss important matters”. A subsequent study found, to widespread concern, that this number is on a downward trend.

The rise of online social networks, with their troves of data, might shed some light on these matters. So The Economist asked Cameron Marlow, the “in-house sociologist” at Facebook, to crunch some numbers. Dr Marlow found that the average number of “friends” in a Facebook network is 120, consistent with Dr Dunbar’s hypothesis, and that women tend to have somewhat more than men. But the range is large, and some people have networks numbering more than 500, so the hypothesis cannot yet be regarded as proven.

What also struck Dr Marlow, however, was that the number of people on an individual’s friend list with whom he (or she) frequently interacts is remarkably small and stable. The more “active” or intimate the interaction, the smaller and more stable the group.

Thus an average man—one with 120 friends—generally responds to the postings of only seven of those friends by leaving comments on the posting individual’s photos, status messages or “wall”. An average woman is slightly more sociable, responding to ten. When it comes to two-way communication such as e-mails or chats, the average man interacts with only four people and the average woman with six. Among those Facebook users with 500 friends, these numbers are somewhat higher, but not hugely so. Men leave comments for 17 friends, women for 26. Men communicate with ten, women with 16.

What mainly goes up, therefore, is not the core network but the number of casual contacts that people track more passively. …

Put differently, people who are members of online social networks are not so much “networking” as they are “broadcasting their lives to an outer tier of acquaintances who aren’t necessarily inside the Dunbar circle,” says Lee Rainie, the director of the Pew Internet & American Life Project, a polling organisation.

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