Sunday, January 22, 2012

Weekend Post - How well do you know your science?

How well do you think you know basic science? Do you think you can answer the sort of questions your kids will ask you about the world?

A survey done recently in the UK by The Big Bang UK Young Scientists and Engineers Fair found that two-thirds of British parents are stumped when their kids ask them scientific questions. A quarter of them find it embarrassing that they can’t answer them. That’s particularly bad because one third of parents say their kids ask them science questions every day.

The good news is that the kids are clearly curious about science and want answers. The bad news is that most British parents can’t answer them.

So what are the questions British kids are asking their parents that are proving so difficult to answer? Here’s a sample of the most commonly asked, and least commonly answered questions. See how you do.

1. Why is the moon sometimes out in the day?
2. Why is the Sky Blue?
3. Will we ever discover aliens?
4. How much does the earth weigh?
5. How do aeroplanes stay in the air?
6. Why is water wet?
7. How do I do long division?
8. Where to birds / bees go in winter?
9. What makes a rainbow?
10. Why are there different times on earth?

Of course some of them are more difficult than others. Whether we’ll ever discover aliens is up for debate. They’re probably out there but they’re so staggeringly far away that our current understanding of physics suggests we’ll probably not make proper contact with them any day soon. And why they’d want to travel all this way to see us is arguable.

Some of the others, like why the moon is sometimes visible during the day, are fairly simple to answer and I’d be surprised if anyone had much difficulty. However some, although they are perfectly reasonable questions to ask, might challenge a lot of us a bit more. Why IS the sky blue? How DO rainbows form? Why do aeroplanes stay up in the air? With a little luck, and assuming you were paying attention that day, you might remember a few things from your school science lessons. You’ll remember forming rainbows with glass prisms in the science lab, studying the migration of birds and perhaps even a few things from geography.

One thing I found pleasing in the study was that a third of all the parents questioned said that if they didn’t know the answer to one of these questions they do some research and find it out. Particularly in these days of easy internet access it’s not difficult to find the answers for yourself. For instance if you do a Google search for “Why is the sky blue?” you’ll get 81 million hits. Of course some of them will be nonsense but the first ten were all correct and all mentioned how the different colors in white light are scattered by air molecules to different degrees, and how blue light scatters the most. The most scattered light hits our eyes from the most scattered area, leaving the other colors to travel more directly from the sun. Not only is that why the sky is blue, it’s why the sun is yellow.

If you can figure that one out, the rainbow question follows on quite nicely although this time with water droplets refracting the colors within sunlight to different degrees. Incidentally, despite what a rather aggressively religious acquaintance once told me, knowing how a rainbow is formed does NOT make it any less beautiful and impressive. In fact, I think it makes it more wonderful.

What about some bad news? Over 20% of the parents sampled said that if they didn’t know the answer to one of these questions they would either make one up or claim that nobody knew the answer.

One of the suggestions of this study is delightful. Their spokesman, Professor Brian Cox, who you may have seen presenting science programs on DSTV, said:
“the best thing parents can do is work with their children to find the answers – not only can it be fun, but you’ll both learn something new along the way.”
I can’t think of anything better than finding out scientific, absolute truth with your children.


The web site of the The Big Bang UK Young Scientists and Engineers Fair can be seen here. You can download their press release (it's a 193k Microsoft Word document) here.

Some answers to the questions can be seen here at the following links:

Photo c/o Wing-Chi Poon
1. Why is the moon sometimes out in the day? Ask NASA. They should know.
2. Why is the Sky Blue? No, it's not because God is a boy. It's because of differential scattering.
3. Will we ever discover aliens? A Russian astronomer thinks so.
4. How much does the earth weigh? A lot.
5. How do aeroplanes stay in the air? My lesson for today. I thought it was just Bernoulli's principle but it's more complicated than that.
6. Why is water wet? It's not. "Wet" is just a word we use to describe the feeling of water. Call a philosopher.
7. How do I do long division? I honestly don't know, I was sick that day at school. Honest. Answer here.
8. Where to birds / bees go in winter? Bees hibernate, with birds it's more complicated.
9. What makes a rainbow? Water droplets make rainbows.
10. Why are there different times on earth? The Earth is a sphere and it can't all point in the same direction at once.

Saturday, January 14, 2012

Weekend Post - Evolution is happening all around us, we just don’t see it.

Evolution is happening all around us, we just don’t see it.

The problem with witnessing evolution happening is that it’s slow. VERY slow. Not as slow as mountain formation and continental drift but nevertheless really, really slow.

Let’s just recap. Evolution is the slow change in form of a species over multiple generations. Each generation perhaps changes a little, tiny, almost invisible amount but after many generations a noticeable change can be seen.

The changes happen because of the way that plants and animals reproduce. Almost all of them reproduce sexually. Two parents share their genetic information to produce a child. Some of the mother’s characteristics show up in the child, some of the father’s but occasionally there’s an error in the mix and strange things emerge, some of them good, others bad. Every so often one crops up that gives the child an advantage, the sort of advantage that will improve his or her chances of reproducing and passing on that advantage to their offspring. Nature, in effect, selects that child to pass on his or her genes more than a child without the advantage. That’s what Darwin called Natural Selection.

The problem with witnessing human evolution is that most of us don’t even consider making babies for at least 20 years. Even those of us who are VERY lucky will only ever see perhaps 7 generations in our family. I for instance met my great-grandparents and with luck I might meet my own great-grandchildren but seven generations isn’t enough for any major change in form to emerge.

That’s why geneticists are forced to choose other species to examine, ones that breed much more rapidly. Their favourite is the fruit fly. That’s because they can breed only 10 days after birth, allowing dozens of generations to be examined in a year. Also, even though they have an extremely simple genetic make-up with only 4 chromosomes (humans have 23) they nevertheless share most of the genes for disease that humans possess.

Perhaps the most famous example of evolution actually being observed was the Peppered Moth. This was a common moth in England that was normally white with black speckles but a tiny proportion were born much darker. The paler moths were clearly at an advantage when they rested on the pale, lichen-covered trees they called home and the darker ones never lasted very long before predatory birds had them for lunch.

As the Industrial Revolution began and the countryside became more and more polluted it was noticed that over many generations the moths gradually changed their coloring to match the increasingly darkened environment. Eventually 98% of the moths were born black. Clearly the moths with the paler coloring became increasingly visible to the birds that ate them and the ones who happened to be darker were more likely to avoid the birds. The darker ones passed on this genetic advantage to their children and over time almost the entire population became dark.
The Peppered Moth: Before (Picture taken by Olaf Leillinger)
The Peppered Moth: After (Picture taken by Olaf Leillinger)
Rather wonderfully, when the pollution finally subsided and the environment became paler again, the moths gradually changed back to their original color. Although this wasn’t a change of species into another it certainly demonstrated that the form of a species can change remarkably rapidly when the environment demands it.

Similar effects have been seen in fish, for instance the South American guppy, again with a fairly rapid change in their camouflage. As with the Peppered Moth camouflage is a great way of staying alive, or of being eaten by a predator if it fails, before you get a chance to pass on your genes.

What about humans? Are genetic mutations going on right now that might give some people an advantage? Certainyly. There’s a town called Limone sul Garda in Italy where a small proportion of the community have a mutated version of a protein that protects them against cardiovascular disease. They’ve even been able to trace the mutation back 300 years to the original “mutant”, a man called Giovanni Pomarelli. Drug companies are doing their best to make an artificial version of the protein that you and I can take. It’s either that or we send our children to that town in Italy to make babies with Signor Pomorelli’s descendants and get the gene into our family as well.


For a good introduction to evolution see the Wikipedia page here. That page contains a summary of Natural Selection but there's a fuller description here.

If you want to know more about the fruit fly see the Wikipedia page here. For details on their disease gene similarity to humans see here.

There's a very good summary of the evolution of the Peppered Moth here. Details of the micro-evolution of the South American guppy can be seen here and a profile of the biologist concerned, John Endler here.

Finally you can see details of the fascinating advantageous mutation in Italy here and here.

Weekend Post - The New Year is a bad time for science

The New Year is a bad time for science. Part of it is the ridiculous New Years resolutions that so many of us make each year. Most of them, and I confess I’m not immune to this, involve promising yourself that you’ll live more healthily. You’ll promise to cut back on the booze, the saturated fat and the chocolate.

Unfortunately the purveyors of pseudoscience know this and shamelessly exploit our good intentions.

A few days ago I saw an advertisement on TV for the completely nonsensical “Detox Foot Pads”. According to the advert you stick these pads to the soles of your feet at bedtime and they apply warmth to your reflexology points and "detox your body while you sleep". The advert claims that this boosts your immune system. According to the personal testimonials from a range of grinning faces you wake feeling refreshed and with "less toxins and impurities".

According to the various characters presenting these pads they generate "far infra-red radiation equivalent to a full cardiac workout". The graphics they showed of two glowing feet were apparently "Thermo X-Rays" that showed "the incredible effects". Actually it looked more like a kid's drawings of feet with wobbly orange spots but maybe I'm too cynical and perhaps "Thermo X-Rays" are a bit of medical technology I've missed over the years.

Unfortunately they fail to point out that everything they say is complete rubbish.

To begin with there’s the reflexology angle. Reflexology is based on the notion that the soles of your feet are somehow connected to every other part of your body. Reflexologists will tell you that stimulation of specific spots on your feet can remedy problems in related organs of your body. However, it overlooks the fact that these connections simply don’t exist. They’re not there. Nowhere. They are as imaginary as the supposed benefits that reflexology offers. Bring me an anatomy textbook and we can fail to find these mythical connections together. There is no scientific evidence whatsoever that reflexology is anything more than just a comforting foot massage. If you like your feet massaged then good luck to you but don’t expect any medical benefits from it.

Then there’s the issue of “detoxing” through the soles of your feet. The advert shows some used foot pads and, amazingly, they are all blackened with what we are told are the toxins extracted from your feet. No chance that the dirt could just be from dirty, sweaty feet is there? Feet are actually horribly dirty things. Why do you think they smell so bad if not washed?

Then there’s the whole issue of detoxification in general. The whole detox industry is based on a series of lies and deceptions. A BBC news story a couple of weeks ago discussed this. A variety of doctors pointed out that thinking of “detoxing” your liver after the Christmas and New Year festivities was a complete waste of time. Despite the claims of the many detox remedies aggressively advertised over the break, none of them offer any real benefit. One of the doctors quoted by the BBC said:
“Detoxing for just a month in January is medically futile. It can lead to a false sense of security and feeds the idea that you can abuse your liver as much as you like and then sort everything else with a quick fix.”
In fact the best way to get healthy after the over-indulgence is just to stop over-indulging and to make a few simple lifestyle changes to protect your health. Your liver is a remarkable cleansing machine so long as you treat it with a little bit of respect. It will do all the detoxing you need if you let it. You don’t need silly footpads, reflexology or any other pseudoscientific claptrap to help get back to good health.

Although detox foot pads are certainly harmless, the danger is that they could be used when real medical help is called for, not just a placebo. They also spread lies about how your body works. That can only lead to danger.

While I think that satellite TV, newspapers and the internet are wonderful things they also have the ability to spread deception, dangerous conspiracy theories and outright lies. Detox foot pads may be a relatively innocent example but they are not that far from things that threaten our welfare, maybe even our lives. Sometimes the detoxing we need is not of our bodies, but of our brains.


You can see a version of the ad I saw on DSTV here. It's a US version of the ad with US contacts and prices but you'll hear that all of the "happy customers" are South Africans.

You can see an enormous variety of critical comments about these nonsensical foot pads as follows:
For a skeptical review of the utterly ridiculous concept of reflexology see the Skeptic's Dictionary article here.

The BBC story about the silliness of detoxing can be seen here.

Thursday, January 05, 2012

Weekend Post - Is this the year that the world will end?

Is this the year that the world will end? No, it isn’t and next year won’t be either.

For several years we’ve been hearing a whole lot of nonsensical speculation about 2012 being the year of the end of the world. If you do a Google search for the exact phrase “2012 end of the world” you’ll find over 18 million hits, almost all of them suggesting that this is somehow true. One of the most important things to know in the 21st century is that just because something’s on the Internet that doesn’t mean it’s true. In fact I’m tempted to suggest that if something IS widely mentioned on the Internet then it’s almost certainly rubbish. The 2012 prophecies are a fine example of that.

To begin with let’s face a simple fact. Without doubt, every single prediction of the end of the world so far has been wrong. Every one, without exception. Not once has the world ended. By this stage surely we should have cast aside end of the world predictions along with witch-burning, reading chicken entrails, astrology and homeopathy. They’ve never worked in the past, they have no rational basis and they’re just plain silly.

However, because each of these things persists those of us who believe in the power of the scientific method and reason have to confront them over and over again.

Let’s start with the main 2012 production. One of the popular things you’ll see is the idea that a Mayan calendar reaches a major turning point in 2012, often referred to as the end of a “Great Cycle”. Even if this were true does it actually mean anything? It’s no more than just the end of a calendar, no more meaningful than reaching 31st December or my birthday. The date is just arbitrary.

But this business about the end of the Great Cycle is nonsense anyway. According to the Foundation for the Advancement of Mesoamerican Studies: “there is nothing in the Maya or Aztec or ancient Mesoamerican prophecy to suggest that they prophesied a sudden or major change of any sort in 2012. The notion of a ‘Great Cycle’ coming to an end is completely a modern invention.”

So if it isn’t the Mayans predicting the Apocalypse, who is it? Ironically it’s a strange mixture of fundamentalist Christians who predict the end of the world every year, astrologers and New Age claptrap purveyors.

I’m not going to comment on the US TV and radio evangelist predictions of the Apocalypse. Instead I’ll just refer you to last year’s predictions by Harold Camping and his gullible followers who plastered billboards all over the world with detailed predictions of Judgment Day in both May and October last year. Unfortunately for them and fortunately for us we’re still here.

Astrologers have been predicting that in 2012 a “galactic alignment” promises doom for us all. However here’s another slightly inconvenient truth. This galactic alignment is a true as the end of the Mayan Grand Cycle. It’s not true. According to NASA, who should know about these things: “There are no planetary alignments in the next few decades, Earth will not cross the galactic plane in 2012, and even if these alignments were to occur, their effects on the Earth would be negligible.”

So still no evidence.

Another often-Internet-quoted belief is that there’s a mystery planet on it’s way to destroy us. Sometimes it’s just called Planet X or other times “Nibiru”. Again let me quote the people who know about these things, NASA. “Nibiru and other stories about wayward planets are an Internet hoax. There is no factual basis for these claims. If Nibiru or Planet X were real and headed for an encounter with the Earth in 2012, astronomers would have been tracking it for at least the past decade, and it would be visible by now to the naked eye. Obviously, it does not exist.”

Perhaps the biggest hurdle in getting rational people to believe that all of this is nonsense is Hollywood. Every year there’s a disaster movie that features the end of the world, caused either by something from outer space or something closer to home. We all have images in our heads from films like Armageddon, War of the Worlds, The Day After Tomorrow and 2012. Just because Hollywood has made a film about something doesn’t make it real.

I know it’s a forlorn hope but I’m an optimist. Why don’t we all be rational this year and cast aside the thoughts of supernatural doom? Let’s face the real threats like poverty, unemployment and hunger rather than made up ones?


Correction: The Google search for "2012 end of the world" now has 21 million hits.

National Geographic (who know stuff) has a very good and entertaining summary of various 2012 myths here. The excellent material from NASA (who know everything) is here. A very comprehensive response from the Foundation for the Advancement of Mesoamerican Studies (who seem to know what they're talking about) can be seen here.

Finally if you want to see a list of the "Top 10 Apocalyptic Movies" go here. Warning, some of the films are very good (I Robot, Andromeda Strain, The Terminator), others are just terrible (Armageddon, Independence Day).