De-bunking that suspicious science...

The Naked Scientists love chatting about mythconceptions; the common myths that can be de-bunked by science! Izzie Clarke is joined by physicist Ben McAllister, plant ecologist Howard Griffiths, chemist Kit Chapman and reproductive physiologist Bill Colledge who all brought in their own myths.

Ben - Right. Mine’s actually more of a science history myth than a science myth itself. I figured given that I’m here to represent the physical sciences I might confront a common myth about one of the most famous physicists of all time. You may have heard the idea that Albert Einstein supposedly failed some maths tests in school or maybe it was in university or something. And yeah, that’s not really true. He was something of an unconventional student, there is a bit of truth in that. He didn’t get along with his teachers, he didn’t like the way things were normally taught, he had a tendency to sort of not pay attention in school. But all signs point to him doing maths quite well at all times which probably makes a fair amount of sense if you think about the career he went on to have. But the origin of the myth is that when he did try and get into university he did fail his entrance exams, but it was not because he failed the maths section, it was because he failed the botany, zoology and language sections. So perhaps someone here on the panel could have helped him out there but yes, in the mean time, he was alone.

Izzie - Do we know where it came from or is it just one of those ones that just floating about?

Ben - Yeah, I think probably just spawned out of that, the fact that somebody read somewhere he failed is entrance exam into university and then wanted to create some kind of pseudo-inspirational myth surrounding it, which is a nice story. “Albert Einstein, one of the greatest physicists of all time, failed his maths, so if you're bad maths you might be good later,” I guess is the message. I don't know but yeah, something like that.

Izzie - If anything, he went on to be a very, very important person for the world of physics and maths. Howard, what are you putting down as a mythconception?

Howard - Okay. What really gets me wild is when I hear regularly on TV and radio programmes that the rainforests are the lungs of the Earth. Now don't get me wrong, I think trees are absolutely vital. I want to plant more trees. I want to stop people cutting down forests because forests are absorbing carbon, they're protecting us against climate change.

But, when that phrase is used, it's often used to infer that the oxygen we breathe is being produced at this minute by the forests. And what you've got to remember are that forests are really giant compost heaps. There's as much rotting, degrading and material just being respiring and consuming oxygen as there are in the photosynthetic leaves above which are producing oxygen, so there's roughly a net balance.

Izzie - Okay. So do you know where the majority of our oxygen comes from?

Howard - Well, it did come from plants. It's come from plants both in the marine system and on land over the last 2.4 billion years and gradually, organic carbon made by plants has been buried either underground in the sediments, turned into rocks and so on, and that’s trapped carbon. Some of its turned into fossil fuels which, of course, we're now burning and releasing CO2 back to the atmosphere. But that's where the carbon went and that allowed the oxygen to gradually increase in the atmosphere.

Izzie - Thanks very much Howard. Now Kit, what are you putting down as something that gets on your nerves?

Kit - This myth that you can’t turn lead into gold. You absolutely can do that. You don't want to do that, but you can do it.

Izzie - How would you do that?

Kit - Well, in 1980 there was a very famous chemist called Glenn Seaborg and he was a nuclear chemist. And what he did was he got a particle accelerator and he fired carbon and neon atoms at a piece of lead and chipped off some protons, and protons decide what element you have and he bashed it way back down into gold.

Izzie - Right. Why aren't we all trying to make gold then?

Kit - This is the problem. To fire up a particle accelerator is a bit expensive. It cost him around $120,000 a day to do it.

Izzie - A day... wow.

Kit - So he worked out that to make one ounce of gold would cost one quadrillion dollars.

Izzie - Come on guys, we can put that down together, no?

Ben - It's definitely something we could scale as well. Maybe it cost that much today, but we’ll push that down in time if we all put enough effort into it.

Izzie - Bill, how about you?

Bill - Well this is a sort of myth that I’d like to debunk which is aimed at couples that are trying to conceive. And people are told that if you’re trying to conceive there’s a window of fertility which is the best time around the time of ovulation for the woman, and if you’re having sex around that time you should have intervals. You should have sex every other day. And it was thought that this is to allow the sperm to build back up to increase your chance of conception.

And actually, it’s completely not true. The best way to conceive during this window of fertility, the window of opportunity, is to have sex as often as you can, provided you’re up to it of course. And the reason that we now know it’s best to just have sex frequently comes from IVF clinics where men have gone in, they’ve given a sperm sample and then they’ve taken another sperm sample two hours later, and often the second sperm sample has more sperm than the first. So basically, you can have just have sex as often as you want during this fertile period and that will improve your chances of conception.

Izzie - Do we know why that happens that a few hours later there is a higher sperm count?

Bill - Well, we make a lot of sperm very, very rapidly. I think that we’re making 5,000 sperm every second - well we are, I’m afraid you’re not. But men are making 5,000 sperm or so every second so we’re making millions of sperm over a few hours. And I think what happens is that the first time you make sperm there maybe some there that has been sitting around for a while, whereas two hours later it’s sort of fresh stuff so they’re much more virile and much more potent.

Izzie - We talk about this ovulation period, the golden opportunity, six or so days a month, can a woman get pregnant outside of that period?

Bill - There is a reproductive window during which a female is likely to get pregnant and it lasts for about six days. The reason it is such a short window during the whole of the cycle is that an egg is only viable for about 12 to 24 hours once it's released. Sperm cells are a bit more robust, they can be viable in the reproductive tract for up to 5 days. So if you put these two together you've got a window of about six days when you're more likely to conceive, and outside this window you're ultimately much less likely to conceive and women often use this natural sort of rhythm method to monitor when they're going to ovulate and to make sure that they don't have sex close to that period.

Izzie - We're going to get to contraceptives later but is that a reliable method of contraception?

Bill - It's not the most reliable method of contraception. I think if you use that method you have to be prepared for failure some of the time. There are more reliable methods.