Looking Out To Sea

Last night’s Café Scientifique was a special outing to the Edinburgh Camera Obscura (which I think is a great place to visit anyway). The talk was given by Will Hossack from the University of Edinburgh.

It was a very good talk (they’re so variable it’s impossible to recommend from one week to the next) — just a shame that the room was too small and too hot for the purposes. It was a windowless room on the fourth floor full of optical illusions and bright lights. Good fun to wander round and play with the exhibits but not great when sitting cheek to jowl on little seats.

But anyway. He explained the general process of laser cooling, by trapping particles with beams of light. Then he went on to describe the work he does with fairly large objects (yeast and fungal spores as well as latex spheres) using the trapping effect to create optical tweezers which can move objects up to a dozen microns in size.

They’ve been wiring up these computer-controlled optical tweezers to some 100x microscopes, and he had some fascinating videos of the things one can do. Apart from getting latex spheres to dance an eightsome reel, he also had a streamer of DNA anchored at one end by the tweezer. The other end was being forced out by the flowing solution it was all bathed in. You could see the long streamer collapse in a flash into a tight little ball when they added some enzyme. Very cool.

It looks like the Edinburgh Café Sci has had a little injection of fresh ideas from teaming up with the post-graduate science communication team (this jolly to the Camera Obscura was their idea) so I hope they follow through with more interesting visits.

I finished this at least a week ago, but I’ve been having a hard time putting in to words what I want to say. The book is The Man Who Mistook His Wife for a Hat by Oliver Sacks. It’s a collection of case notes about people he saw over the years in his work as a neurologist. Straightforward enough.

You must read this book.

That’s really all I need to say, though you probably feel a bit more explanation is required. Essentially, the book is a testament to the fragility of our minds. Most of the stuff we understand about the mind (hell, about biology) comes from what we can learn when it breaks. This book is about all the ways it can break.

• There are people who lose all sense of “ideal” entities. The man could hold a glove but only recognise that was soft cloth, that it was a container, that it had five little pouches.
• There are people who lose all sense of their body. The woman did not know what her limbs were doing when she wasn’t looking directly at them.
• There are people who lose all sense of inhibition. The woman would involuntarily mimic every person she saw as she walked down the street.
• There are people who lose huge chunks of their past, or who continually lose the immediate past.

If ever there was a book that showed the mundane, tangible nature of the brain, it is this. Everything that you can think of, every ability you have, is centred somewhere in that bundle of neurons in your skull. And if some of them should fail you could lose your ability to recognise faces, to recognise your own leg or to even understand the concept of “left”, the opposite of “right”. Can you imagine that?

I have, so to speak, finished Climbing Mount Improbable. In the sense that I have read the book but also that I am at the peak of evolutionary fitness, because I am alive.

On my old blog I wrote about blind search as a hill-climbing metaphor. Richard Dawkins uses this same idea to describe how various features such as wings, eyes, colourful flowers and such could have evolved. The idea is just as I described:

Searching for things in computer science is often likened to climbing a hill, where the summit represents the goal, and every point on the landscape represents a candidate for this goal. The idea is that, without knowing where the summit is, one can get there by always walking up hill. Assuming an ideal (smooth) landscape one could get to the top of a hill blindfold. (Not recommended.)

Each step is just a simple adjustment, a tiny, unlooked-for variation in the population. This variation will mean the animal that has it is at a tiny advantage and may spread its genes wider than average. Thus we can get from nothing, to the human eye; or from a similar nothing, to the bird’s wing; or from nothing to the intricate ecosystem that is the fruit of the fig tree.

And like I stated in my other post, scaling a mountain blindfold is possible, but can lead to dead ends:

If we can’t see where we’re going then we can never be totally sure if we’re on a minor summit rather than the very top of the mountain. This is called a local maximum — every direction you walk goes down, but there is a direction which will eventually take you to a taller peak.

Unfortunately, evolution doesn’t have the advantage of predicting these problems. So if chance chooses a particular short-term solution which later leads to problems (like the blind spot in our own eyes) there is nothing to be done. There is no option to back-track and start again down a different route — only forward and up.

The book’s very interesting, and certainly very readable. One of the middle chapters on segmentation of insects was a bit tedious. I’m not sure if this is because he was explaining something obvious in great detail, or because it was obvious that the detail was being expended on a description of a computer program to demonstrate something obvious, which itself was obvious. The abstractions he described were rather uninteresting, to me at least. Maybe others would find them less apparent.

I would have preferred, instead, that the final chapter be longer, or even split into two. It had some extremely complex relationships laid out without much differentiation. Indeed there were two types of wasps described in this chapter, the ‘true’ fig wasp and the fake fig wasp, both called fig wasp. Some aliases and maybe a diagram of the relationships would have made this chapter much clearer. And possibly more interesting for it.

Overall I was surprised how short the book was. It only took me a few days to finish and I wasn’t devoting much time to it — I was ill and it was a busy Christmas, after all. I would still recommend The Selfish Gene over this any day.

Like it says, it’s a book about mosquitoes, and it’s got a massive picture of one on the front, looking all creepy-buzzy otherworldly. It’s written by a mosquito-borne infection expert and a journalist (Andrew Spielman and Michael D’Antonio respectively), which makes it both readable but also strangely artificial. There are scientific bits interspersed with bits that seem forced and too-friendly, as if to compensate for actually talking about the facts briefly.

There’s a lot of detail about the life-cycle of mosquitoes and the different places they breed, which ones bite and why, their post-prandial behaviour and so on. Then there’s loads on all the horrible diseases they spread, how they move from person to person, which animals act as reservoirs but don’t develop symptoms, etc. But through all that, the disease I know least about is malaria. I actually had to ask Helen what it was (it’s some sort of parasite, apparently) because the book doesn’t explain at any point. That’s just downright weird.

It’s a pretty enjoyable read, with some very interesting background to the story on DDT. There are an awful lot of conspiracy theorists about who believe Rachel Carson (author of Silent Spring) is the Great Satan and responsible for more deaths than Hitler and Ming the Merciless combined. In reality, it was well known at the time that DDT was losing its edge because of over-use. The heavily sprayed areas were seeing resurgence in malaria from newly-resistant mosquitoes. The environmentalist movement was only one nail in the coffin.

There are a lot of stupid things in this world, and although automated grammar checking doesn’t rate as very important among them, it is still very stupid. Trying to get real, human grammarians to agree on points of grammar (especially in a language as mongrelised as English) is bad enough. Add in to the mix the inevitable artistic desire to break and reforge rules, and the computers have no chance at all.

But they keep on trying, letting Microsoft Word infuriate people on daily basis with the suggestion that they might want to change “which” to “that” (or is it the other way round?).

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