What 100 year flood means

“And this is where you first start getting a sense that maybe engineering hydrology isn’t the most exact of sciences. …none of the Imperial units for these values agree, but if you do the math, the conversion factor is just about one, so we ignore it. We just leave it off! This is not something we take out to the fifth decimal place.”

Human microbiome transplant

Responses to Josiah Zayner’s attempt to replace his body’s bacteria are almost as interesting as the experiment itself. It seems like most of the medical community believe professional approval of one’s theory and practice is what determines therapeutic success, and not the actual measurement of physical outcomes.

Anyway, as is usual in gut flora replacement therapy, Mr. Zayner has successfully remediated his long standing intestinal problems. Genetic tests show that he is now host to a new, healthier mix of internal bacteria harvested from a friend’s feces. The rest of his homemade treatment was less successful; he was not able to completely eradicate his skin bacteria, nor was he able to prevent re-infection from his surroundings. The article is sort of simultaneously horrifying and illuminating; scientists who self-experiment are strange birds more often than not.

Radioactivity Art

Greenpeace photographer Greg McNevin has created a beautiful series of photographs based on walking around areas formerly contaminated by the ongoing Chernobyl and Fukushima nuclear disasters with an LED stick connected to a geiger counter. It’s unfortunate that most people won’t be able to see the art past the politics, but I think it has value in both spheres.

Evolutionary Psychology, Memes and the Origin of War

Somebody (possibly Henson himself) posted Evolutionary Psychology, Memes and the Origin of War over at Kuro5hin in 2006. I had no idea Kuro5hin still existed, and Henson’s paper could use some consideration of group selection, but anyway it’s a worthwhile and controversial read.

It seems to me that if Henson’s basic thesis is right, our current global political situation is not just eerily similar to that of the mid-1930s, it’s actually the same phenomenon – so we better get it under control.

killing wildlife doesn’t make your food safer

In an ill-considered response to a 2006 e. coli outbreak, for years now food sellers have been pressuring food growers to turn the areas surrounding farms into a blasted, sterile wasteland, devoid of any wildlife.

A recently published paper shows that this practice is not beneficial, and has measurably decreased food safety.

Blasted wasteland surrounding a farm

“There is this misguided idea that agricultural fields should be a sanitized, sterilized environment, like a hospital, but nature doesn’t work that way.” — Daniel Karp, postdoctoral research fellow UC Berkeley Department of Environmental Science, Policy and Management.

Well, now, about those hospitals, Dr. Karp…

Dillon Marsh: For what it’s worth

These images combine photography and computer generated elements in an effort to visualise the output of a mine. The CGI objects represent a scale model of the materials removed from each mine, a solid mass occupying a scene showing the ground from which it was extracted. By doing so, the intention is to create a kind of visualisation of the merits and shortfalls of mining in South Africa, an industry that has shaped the history and economy of the country so radically.

new discovery in science of blowing up stuff

Alkali metals can react explosively with ​water and it is textbook knowledge that this vigorous behaviour results from heat release, steam formation and ignition of the ​hydrogen gas that is produced. Here we suggest that the initial process enabling the alkali metal explosion in ​water is, however, of a completely different nature. High-speed camera imaging of liquid drops of a ​sodium/potassium alloy in ​water reveals submillisecond formation of metal spikes that protrude from the surface of the drop. Molecular dynamics simulations demonstrate that on immersion in ​water there is an almost immediate release of electrons from the metal surface. The system thus quickly reaches the Rayleigh instability limit, which leads to a ‘coulomb explosion’ of the alkali metal drop. Consequently, a new metal surface in contact with ​water is formed, which explains why the reaction does not become self-quenched by its products, but can rather lead to explosive behaviour.

water droplet included for comparison

Group dynamics and prototype theories of cognitive neuroscience

Humans are pack animals. They need to gather according to shared traits and then see an enemy of everyone who does not fit.

— Some geeky guy on Slashdot.

Computer scientists are taught classical categorization, which has little correspondence to how our brains actually categorize. The Aristotelian “necessary and sufficient” check-lists of traits, on which we’ve built giant monoliths of computer code (hello, Active Directory) and theory (hello, cladistic phylogeny) are something like the phlogiston theory; a bluntly workable model, that lets you get things done, but also fundamentally wrong, and thus a limitation on what can be understood and predicted.

Research that’s been ongoing since the 1960s or earlier, by people like Eleanor Rosch and Paul Kay, and later George Lakoff and Ronald Langacker, has provided significant amounts of data showing our brains do not assign people to us/them categories because they have a set of traits that we’ve understood and identified. In neurological reality, we assign people to categories based on how closely we think they resemble one or more prototypes, which might be real people (a group leader, typically) or an idealized belief or perception of how men and women should be. The prototype can be fixed (like, say, Jesus) or constantly changing (like, say, a political candidate).

There will always be someone in the group who least resembles the prototype, so there is always a scapegoat available if there’s not enough food or someone needs to take the blame for some unavoidable accident. There may also be anti-prototypes and whoever most resembles that person is less “in the group” than someone who is otherwise the same but lacks these correspondences with the anti-prototypes.

In a strange way this confirms one of Cipolla’s famous “basic laws of human stupidity“; since we’ve evolved a categorization method that mainly serves to quickly identify who gets thrown off the sled when the wolves are catching up, of course there will always be more than enough people to fill that role. If you need a scapegoat, you’ll always be able to identify someone as the stupid person responsible; our brains are biased to work that way.