Saturday, February 25, 2012

Weekend Post - Pseudoscience

Perhaps the single biggest threat to science and the progress and benefits it offers is it’s illegitimate cousin, pseudoscience. I think it poses a greater threat than all the religious literalists, conservative denialists and political opportunists combined.

So what is pseudoscience? The simplest definition is:
“a set of ideas based on theories put forth as scientific when they are not scientific.”
Someone using scientific sounding language but who is actually spouting scientific nonsense is talking pseudoscience.

A very good example is a piece of glass called the Biodisc that a company called Qnet will sell you. This really is no more than an engraved piece of glass but Qnet will have you believe that the disc “increases luminescence, designed with Biophoton production in mind”. What’s more they say the disc “can reduce water surface tension value. This in turn makes water more hydratious, which therefore improves the compatibility of water molecules with the body’s cells”.

It doesn’t take too much recollection of our school science lessons, or too much skepticism, to realize that this is utter claptrap. I’m not sure how water CAN be made “more hydratious” when that just means “watery”. Extra-watery water is an intriguing concept. However, they get away with this because many people fall for the pseudoscientific language. Referring to “surface tension”, water molecules and luminescence lends the product an air of science, if only because many of us seem to find long words impressive.

The key difference between science and pseudoscience is simple but not obvious. Scientific ideas can be disproven, pseudoscientific ones cannot. Not proven, disproven. It would be the easiest thing in the world to test the Biodisc to see if it can reduce surface tension. You and I could do that at home with a glass of water, a Biodisc and a needle. I know, I did a similar experiment with my Dad as a kid.

I admit that the Biodisc is a silly example, as well as being a silly product. It does precisely nothing so the only thing it can harm is your bank balance. The real danger is from pseudosciences that might actually have an impact on you and me or the people we care about. The father of modern scientific philosophy, Karl Popper first spotlighted Freudian psychoanalysis as a pseudoscience. All of Freud’s theories of unconscious desires, the id, ego and superego, are all based on assumptions and theories that aren’t properly testable. They can’t be disproven. So psychoanalysis isn’t scientific. It also doesn’t help that it’s hogwash.

The contrast that everyone draws is with Einstein’s theories of relativity. These theories would be very easy to disprove. They all make predictions about the behavior of light, gravity, space and time. So far every time they’ve been tested they’ve held up well under the strain. Of course one or all of them might be disproven tomorrow, it just hasn’t happened yet. It’s safe to assume for now that they’re correct.

Even worse than pseudoscience is scientific fraud. The history of science is littered with theories that have been put forward, thoroughly tested and disproven but which stick around because someone is making money out of them. Homeopathy is a good example. Homeopathic “remedies” contain no active ingredient. The pseudoscientific idea, one that has been disproven countless times, is that the water somehow remembers an ingredient it once contained but that has subsequently been diluted into nothing. It’s utter nonsense but you still see them being peddled by pharmacies all over the place.

However, at worst homeopathy is no more than a waste of money. It gets worse. There are pseudoscientific claims that kill people. For once I’ll overlook the HIV/AIDS denialists. We’re lucky enough to live in a country where I’m sure we’ve all see the impact of HIV and, just as importantly, the impact of anti-retroviral drugs. We all must have seen a relative or friend whose life has been improved almost immeasurably when they started taking ARVs.

But that’s not all, there’s also the whole “debate” about the causes of autism. There was a brief period when mercury poisoning was thought to play a role in the development of autism, particularly the mercury that was once in vaccines given to young children. This fear was based on a number of pseudoscientific ideas.

It began with the coincidence that autism often starts to develop around the time many kids get vaccinated against diseases like measles. But coincidence is not the same as causation. Kids also learn to ride bicycles at that age but nobody thought that bicycles cause autism. There is, and this is actually quite simple to understand, even for objectors to vaccination, whatever their motivation, absolutely no evidence of any relationship between childhood vaccinations and autism. None whatsoever. The effect of these denialists, using their pseudoscience, was to kill small children. After years of various countries being almost free of certain diseases, children started to die again. That’s where the danger lies. Pseudoscience kills children.

Sources

For a comprehensive overview of pseudoscience (and the definition I gave) see the Skeptic's Dictionary.

If you want a laugh take a look at the Biodisc here on the Qnet web site.

There's a comprehensive profile of Karl Popper on Wikipedia along with many links to other sites about him and his work.

For information on the absence of a link between mercury and autism see a Reuters story and a good description of the whole controversy here. Also see the Skeptic's Dictionary article here.

Saturday, February 18, 2012

Weekend Post - Why do zebras have stripes?

Why do zebras have stripes? New research suggests it might be more complicated than you think.

While it would be nice to think that zebras have stripes just so our country can have a cool national symbol I’m afraid we can be that self-centered. The zebra came first.

Let’s begin with an age-old question. Is a zebra a white horse with black stripes, or a black horse with white stripes? We now know the answer. It turns out that when they’re growing in their mother’s uterus zebras begin dark-skinned but develop white stripes before they’re born. You have to wonder why this would happen. What advantages does it offer the baby zebra to invest all that energy into growing such a complicated pattern instead of growing stronger bones, a bigger brain or stronger muscles.

Image c/o Wikipedia here: http://en.wikipedia.org/wiki/File:Zebra_camouflage.jpg
Camouflage is an obvious answer. It might seem surprising to those of us who live in a country with lots of zebras but most people around the world find it shocking to think that a zebra’s stripes might offer it camouflage. How on earth, they wonder, can an animal with such a vivid pattern of such contrasting colors hide in a grey, green and brown environment? That’s until you see them in the wild and you realize that black and white merges at a distance to grey, providing excellent cover in grass, trees and bush.

Clearly that’s something that gives an individual zebra a chance at avoiding lions. Experts estimate that around 4-5 million years ago the first zebras began to appear. Presumably the first horse-like creatures with a hint of stripes must have had a slight advantage over their non-striped cousins. Critically, it must have given them a greater chance of surviving long enough to pass on their genes to their offspring. The unfortunate ones without the stripes would have been more likely to be visible in the bush and provide lions with lunch. Nature, in effect, selected the striped ones to pass on their improved genes. That’s why this type of evolution is called “natural selection”. It’s not a breeder, supernatural or not, who does the selecting, nature does it.

However, it might be a bit more complicated than just being able to hide from lions in long grass. Scientists from Sweden and Hungary recently came up with another reason why stripes might be useful. Based on some simple experiments they found evidence that stripes protect zebras from blood-sucking insects like horseflies.

They started with the knowledge that horseflies are more attracted to darker horses than to paler ones. They wondered whether stripes might somehow disrupt the attraction the dark skins held for the blood-sucking flies. That’s exactly what they found.

The researchers placed various boards of different colors and patterns in the fields surrounding a horse farm in Hungary. These boards were all covered in glue that trapped any flies that landed on them. At the end of the day the researchers just had to count the trapped flies to see which pattern attracted the most. They expected to see most flies on the darker boards, least on the palest and the stripy boards somewhere in between.

In fact they did confirm that darker boards seem to attract more flies but the surprising thing was that stripes were even less attractive to the flies than a white board. When they tried to work out which pattern of stripes were least attractive they discovered that it was exactly the pattern you find on a zebra.

So now it’s a bit more complicated. Stripes provide camouflage and enable the zebra effectively to hide from predators but they also might provide protection against bites. For this new factor to be plausible the researchers need to suggest a way in which this offers the zebras a greater chance of having babies than another that gets bitten more. The spread of disease is an obvious possibility. Fewer fly bites probably means a lower chance of fatal disease.

But there’s more than just this. Other scientists have suggested that stripes enable a herd of zebras to more effectively confuse predators and enhance their chance of escape. It’s even been suggested that the stripes are a complex form of heat regulation.

This is a great example of how evolutionary pressure is complex and often involves a wide variety of influences. It’s one of the things that makes science so wonderfully interesting. Easy, simple answers are often just too easy and too simple. Science is like the rest of life and truth. Deliciously complex.

Sources

You can see the BBC coverage of the story see here. A bit more detail can be seen at The Journal of Experimental Biology here. For a bit of background on the evolution of the horse see the Wikipedia page here. For more detail on the zebra see here.

Saturday, February 11, 2012

Weekend Post: Good and bad news about malaria.

There’s good news and there’s bad news about malaria.

The bad news is that it’s possible we’ve ben grossly underestimating the number of deaths due to malaria over the last couple of decades. New research funded by the Bill and Melinda Gates Foundation and published in The Lancet and reported on the BBC suggests that the true death figures might be twice as high as we previously thought. For instance the World Health Organization estimated that in 2010 that 655,000 people died from malaria. The new research, which was based on a mixture of sophisticated statistical techniques and computer modeling estimated that malaria claimed 1.24 million lives around the world that year. The tragic news is that almost all of those deaths were here in Africa.

That’s the bad news.

The good news is that despite this tragic loss, the number of deaths is decreasing. While that figure is enormous, a mere six years beforehand the number was almost 2 million. The figure appears to have increased to that height in 2004 simply because there were more people living in affected areas. The subsequent drop was down to old-fashioned scientific progress.

I mean old-fashioned because it was based on theory, research and experimentation. In fact much of what was achieved was a wonderful mixture of leading edge science and some fairly old-fashioned techniques.

Not a single element of this progress was achieved using superstition, “alternative” medicine or pseudoscientific claptrap. No religion has ever saved this number of lives.

My favourite is the old-fashioned mosquito net. Nets have been used to prevent people being bitten by mosquitos for centuries. There are even stories that Cleopatra slept under one, two thousand years ago. The barrier idea is as old as the hills, just like the condom. The new element is that these nets can now be treated with a long-lasting insecticide. These insecticide treated nets, or ITNs, cost just a few US dollars and are considered by experts to be the single most effective way of preventing people getting malaria. Research has shown that they can reduce the number of episodes of malaria by up to half.

The nets don’t last forever of course and must be replaced once the insecticide has worn off but for only a few dollars a net that’s not such a huge problem, particularly when international health organisations and charities are paying for them. Better still if many people in a community use the nets the effect is to reduce the overall number of mosquitos in that area so even the neighbours who don’t have the ITNs get some benefit.

One of the interesting debates about ITNs is actually who should pay for them. Although Bill and Melinda Gates, the World Health Organisation and charities around the world are prepared to cough up the cash many experts feel that people will use the nets more if they contribute towards their cost themselves. The notion is that people feel a greater sense of emotional investment in something they’ve spent money on. A freebie is something you’ll care less about perhaps?

Almost as good, and perhaps one day even better, is the prospect of a vaccine against malaria. A couple of months ago a research scientist from GlaxoSmithKline, a drug company and therefore in many people’s minds utterly evil, announced some fantastic preliminary results. Following an 18-month clinical trial involving 15,000 African children an experimental vaccine appears to reduce the risk of contracting malaria by half.

I’m not going to defend the pharmaceutical industry against all the charges laid against it but every so often something like this comes along that is just simply good. A vaccine for malaria would be worth whatever it might cost to produce. The value in saved lives would be beyond a mere price.

Of course the real fantasy is what might happen if we can combine the treated nets AND the vaccine. Is it possible that malaria might go the way of smallpox? Until smallpox was eradicated many people thought it was an unachievable dream but science did that for us. Nobody will ever suffer from smallpox again. Maybe in our lifetimes the same can be said for malaria?

Sources

The BBC story can be seen here. A summary of the Lancet story is here.

For an overview of mosquito nets see the Wikipedia page here and for malaria see here. For the Reuters story on the GlaxoSmithKline vaccine see the story here.

Saturday, February 04, 2012

Weekend Post - You are what you eat

You are what you eat. Literally. Every atom of your body has come from things you have eaten or your mother ate while she was carrying you.

That’s why it important to think about the stuff you stuff down your throat. With the exception of any material your body decides not to keep and instead expels (you know what I mean) what you eat stays inside you. But you know that, we all know that. We all know that eating fairly healthily is what we should be doing. We know to cut back on the red meat, the processed foods, the saturated fats and the booze. While there’s nothing wrong with these things in moderation, the more we insert into our bodies, the more problems our bodies will have.

The danger of course is from excessive consumption of bad things. However, perhaps the worst thing you can have to excess, or even in small doses, is nutritional advice. That’s because a lot of so-called “nutritionists” are dangerous charlatans, pseudoscientific frauds or just plain fools. Many of them pose a greater risk to our health than a deep-fried double cheeseburger with extra cheese.

Which? magazine, the UK’s leading consumer advocacy publication recently did an admittedly unscientific but nevertheless fascinating and scary experiment. They sent three researchers to see a variety of nutritional “therapists” and sought advice on a range of disorders. One claimed to have fertility problems, two complained of persistent fatigue and two claimed to have a form of breast cancer.

What they should have suggested was what they should suggest for anyone, regardless of their health status. Take some exercise, eat lots of healthy food, drink lots of water and cut back on the rubbish. That sort of advice would help anyone. Even people with the illnesses described would probably have indirectly benefited from being a little bit healthier. But that’s NOT the advice the researchers were given.

Twelve of the fifteen urged the researchers to buy supplements, some costing P750 a month. They were also told not to buy them from conventional pharmacies because they weren’t “pure enough”. Instead they were advised to buy them from a particular store recommended by the quack. We can all guess why.

One of the researchers who pretended to have cancer was told to stop any conventional medical treatment and instead to beat the cancer by cutting out all sugar from her diet for three to six months. By then she might have been dead.

In fact only one of the fifteen nutritionists dispensed advice that a panel of experts described as a “borderline pass”. Eight of the fifteen cases were considered “fails” and, worst of all, six were classified as “dangerous fails”. These were situations where the client would have been at severe risk if they had followed the advice they were given.

None of the researchers were advised to consult a real doctor or to have any real tests.

The Which? report says:
“One of the researchers - who had been trying to conceive unsuccessfully for over a year - was diagnosed with a ‘leathery bowel’ by a therapist who used Iridology - looking at iris patterns, colour and other characteristics of the eye to diagnose symptoms.”
It goes on to say that:
“Another therapist recommended hair mineral analysis to check 'essential minerals and toxic metals', while one other 'diagnosed' a researcher as having a chromium deficiency after making him 'hold' different liquids in his mouth.”
This is dangerous quackery of the worst kind. This sort of nonsense runs the real risk of killing people. But this is the UK, this sort of thing couldn’t happen here, could it?

Yes, of course it does, we all know it does. Part of the problem is that we have similar laws to those in the UK. Our Health Professionals Council is required to register Dieticians but not crooks calling themselves nutritionists. You or I could set ourselves up as nutritionists tomorrow. We could advertise the “Deep-fried butter and Whisky” diet, have sex with our clients and promote our own homemade supplements and nobody would have the power to stop us.

Frankly, I suspect it’s safer to eat badly than to visit a nutritionist.

Sources

The Which? article can be seen online here. There's an interesting article on science and pseudoscience in nutrition on the CSI site here.