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Breaking Science: Stress, fish, financial success...

Updated Sunday, 18th January 2009

Important fish, can finger length predict success and are daddy long-legs all that venomous?

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The Breaking Science team explore how fish play an important role in the marine inorganic carbon cycle; how shiny crops could reduce global warming; how stress causes temporary attention problems; the development of wireless micrograbbers that have potential surgical applications; the discovery that finger ratios and testosterone levels predict long-term profitability in high frequency traders; and how rogue antibodies produced within joints themselves causes rheumatoid arthritis.

Plus in 'Stuff and Non-Science', are daddy long-legs all that venomous?


Copyright BBC


Chris Smith: In this week’s show, we’ll be taking a look into the nano toolkit of the future.

Helen Scales: Yes, at under a millimetre in size, scientists have invented a new remote controlled micro tool, and I’m very pleased to say that it’s inspired by a crab’s claw - those lovely creatures, one of those marine things I love - and one day it could be used inside the human body to conduct minute, tiny little experiments.

Chris Smith: Helen Scales, who’ll be talking about this mini metal crab in just a moment. Also on the way, what your fingers say about your fiscal prowess.

John Coates: For a lark, I thought well let’s take handprints from the traders which we did and correlated them with their long-term profitability, and we were absolutely astounded at the result because it turned out that their finger ratios were predicting their long-term profitability.

Chris Smith: John Coates on how finger lengths dictate whether you’ve got the Midas touch. Plus, in this week’s ‘Stuff and Non-Science’ we’ll be finding out where the claim came from that daddy long-legs are the world’s most venomous creatures - which actually they’re not.

Hello, I’m Chris Smith. Welcome to Breaking Science which is produced in association with the Open University. First, let’s take a look at some of this week’s top science news stories from around the world, and tracking them down for us this week is Helen Scales, so Helen, as a marine biologist, do tell us do fish drink like a, well, fish?

Helen Scales: As a marine biologist that’s a top question I get and the answer is yes they do, and for marine fish this leads to something peculiar going on inside their stomachs which might have a link with climate change. Well until now scientists have thought that it’s mainly billions of tiny plants called phytoplankton that live in the oceans that are responsible for absorbing huge amounts of the carbon dioxide that us people emit every year. But now it seems that fish might also play an important role in the carbon budgets of the ocean as well.

Chris Smith: What are carbon budgets?

Helen Scales: Okay, so basically we’re talking about carbon that’s partly in the ocean, partly in the atmosphere. It’s a great big system. We release carbon dioxide into the atmosphere. Some of it will get absorbed into the oceans by these phytoplankton and other things as well.

Chris Smith: So where do fish fit into this?

Helen Scales: Right, well, this is a study by a group of scientists led by Rod Wilson at University of Exeter here in the UK, and he’s published a paper with his team in this week’s edition of the journal Science, and they’ve revealed that fish could actually produce between 3 per cent and 15 per cent of the carbonate in the ocean.

Chris Smith: It’s the same stuff that builds up in the kettle isn’t it? It’s the scale basically; it’s insoluble forms of carbon.

Helen Scales: It’s an insoluble form of carbon and calcium carbonate usually is what we’re talking about here. Now what happens when fish swallow salty water is that the calcium in that water, it reacts in their stomach with the carbon dioxide that comes out of their blood and it forms calcium carbonate, insoluble calcium carbonate. Now the fish don’t hold on to this calcium carbonate that they produce but they get rid of it in their faeces. And up until now no one’s actually thought about how much those fish are actually contributing to the carbonate in the oceans.

Chris Smith: So this is quite important because it says that rather than just the tiny plants locking away the carbon now we’ve got fish in the equation too.

Helen Scales: They’re certainly in the equation - just where in the equation remains to be seen. Now what the researchers have done actually to look at this is they’ve built a model of the oceans and they estimated just how much altogether they might add up, and one of the things that comes out of this study is it seems that under climate change we could see an increase in the rate that fish produce carbonates because they’re cold-blooded. That means their metabolic rate could well go up if the water around them warms up. The question is what happens to that carbonate once they’ve created it?

Chris Smith: Well quite because at the end of the day if it doesn’t end up in the deep ocean locked away again it just goes into some other pathway and then goes back into the air as carbon dioxide - a bit risky.

Helen Scales: It could eventually get back into the atmosphere. It is certainly risky but I think the thing that this really highlights in this study is that up until now we’ve assumed that as more carbon dioxide is emitted into the atmosphere the oceans will become more acidic. That’s because carbon dioxide dissolving in water forms carbonic acid. But perhaps fish, there is an important role for them to play, possibly increasingly so.

Chris Smith: Well let’s stick with the climate change scenario and situation for just a second because now researchers are also saying that we need to grow shinier crops because this will help to combat climate change by reducing global warming. Tell us about this.

Helen Scales: Right, well, giving up our global addiction to fossil fuels and curbing our emissions of carbon dioxide could be a long way off. So this new idea could be yes change what varieties of crops we grow because the shinier the leaves of crops the more of the Sun’s energy is reflected back into space, and it could help protect against lethal heatwaves that are predicted to become much more frequent in years to come.

Chris Smith: So leafal or lethal? But how much energy do they honestly think could be returned into space this way? It doesn’t sound terrifically plausible, to be honest.

Helen Scales: Well, what they’re saying, and this is a study in the journal Current Biology this week, and it’s published from a team of researchers from University of Bristol led by Andy Ridgewell, and they looked at by having just 20 per cent more reflections in the crops that we use today, which isn’t really unfeasible, they think we could actually see a one degree centigrade drop in temperatures across Northern America and Eurasia in the middle of summer.

Chris Smith: That’s significant isn’t it? That’s quite a lot.

Helen Scales: So it is significant. You know, it is. It could well make a difference.

Chris Smith: So are we able to get crops like that? I mean is this feasible?

Helen Scales: Absolutely, yes. Already, if you look at the sort of varieties we’ve got available, within that there is a variation how shiny they are. It’s also things like how hairy the leaves are, whether they have a waxy coating on them.

Chris Smith: But the physicists listening to this would almost certainly say well the plants absorb energy from the Sun and they turn that into chemical energy that we then eat. So if the plants are absorbing less energy because they’re reflecting more energy, are we going to end up having to grow more plants just to make up for that shortfall and therefore it’ll shoot itself in the foot?

Helen Scales: That’s exactly the problem that needs to be addressed by this. But in fact it isn’t really that much of a problem, and in fact they aren’t much less efficient it turns out. It’s rather counterintuitive, like you say. But what’s actually happening when there’s more reflectance, it’s something else that’s very important for crop growing, and that's they’re much more efficient at using water and will do much better under drier conditions which is also something that we’re likely to see increasing in the future.

Chris Smith: That’s good because people can get less stressed about that. And you’ve got a story about stress this week, tell us about that.

Helen Scales: That’s right. Have you ever found it difficult to pay attention to things perhaps going on around you, maybe when you’re under a lot of stress? Well, if you have, then you are not alone because scientists this week have published a study revealing that the connections inside an important part of our brains, called the prefrontal cortex, may start to break down when we get very stressed.

Chris Smith: And that’s why you can’t remember things when you try and learn them or crash-learn them, cram them before an exam, because you’re stressed and it's inhibiting?

Helen Scales: I certainly find it difficult or did in the past when I had to do exams, yes.

Chris Smith: So what have this group done to prove that?

Helen Scales: So this is a group from Cornell University and Rockefeller University in the States and their paper is in the journal PNAS this week. What they’ve done is they took a group of volunteers, half of them were medical students, poor things, who were about to sit a major set of exams, and then 20 other people who were much more lucky of similar age and background but who weren’t being put through the rigours of exam time. Now they were all given questionnaires just to sort of test how stressed they were, and of course the ones with the exams were the ones who were, it seemed, much more stressed.

Then what they did, the researchers asked these volunteers to do a series of tests. They showed them a screen with two moving circular dots on in green or red, and they were either moving up or down, and then in between them there was a letter, and it was either the letter M or the letter C, and that was asking them whether they wanted to identify the colour or the motion of the dots. And by repeating these tests in various different combinations you could therefore get a real grip on how quickly they were able to shift their attention and take in new information.

Chris Smith: And how did it compare when you look at the stressed people versus the people that were more relaxed?

Helen Scales: Well what they saw was it was directly proportional to the scores they did on those tests. So the people scoring higher, feeling that they were more stressed, took longer to do those, identifying the colour and the direction of the dots.

Chris Smith: And do they give any insights in the study as to why that might have been?

Helen Scales: Yes, because they got these poor students who were not only suffering from exam stress, they bunged them in a functional MRI scanner to see what was going on inside their brains. And what they found was that this prefrontal cortex part of the brain actually had fewer connections within those people who are more stressed and who are taking longer to achieve these attention shift tests and to identify what was going on in those pictures in front of them.

Chris Smith: Oh God, is this effect permanent? I hope not!

Helen Scales: No. In fact they got these medical students to come back after they’d done their exams. They’d had their celebrations, passed their exams, hopefully. They came back and did exactly the same tests again. And at that point none of these differences came out. They were all really the same and they had gone back to normal and their brains were much as they were before, thank goodness!

Chris Smith: So when they say you need to focus under pressure, then it’s not possible to take on brand new information and that’s where training comes in. I guess that’s why training’s so effective at helping people when they get stressed. Now to finish off this week, this is very exciting, Helen, because I’m a big fan of the nanoscale, and scientists have made a very small pair of pliers, effectively a tiny pair of pincers that might help with lab-on-a-chip technologies.

Helen Scales: Yes, under a millimetre in size, scientists have invented a new remote-controlled micro tool, and I’m very pleased to say that it’s inspired by a crab’s claw - those lovely creatures, one of those marine things I love - and one day it could be used inside the human body to conduct minute, tiny little experiments. Now this is the brain child of a team of researchers led by David Gracias from Johns Hopkins University in the US, and they’ve published their study in the journal of PNAS this week.

Now these tiny little devices look a bit like miniature metal flowers, and they’ve got six tapering petals and they can be triggered to fold up into a minute hexagonal box. Now so-called micro grabbers like this are already being used but up until now they’ve all been connected to wires. But of course the advantage of these new ones is that they’re wireless.

Chris Smith: How do they activate them then?

Helen Scales: Now the secret to how these actually work, it lies in their joints. Now each petal has two joints, a bit like a human finger. Now these new micro grabbers are made from very thin sheets of composite metals, including copper and chromium, so that if you cut these flower shapes out with these joints in them and release them from the sheet of metal they will spontaneously curl up. So what you want to actually do is to control that closing, and you can do that by adding a polymer across the joint, and then you can use various different triggers, depending on what that polymer is, to actually allow the claw to close rather than hold it open.

Chris Smith: So you affect the local conditions, that affects the polymer, and then when the polymer releases its grasp if you like on the flower it can spring closed?

Helen Scales: Exactly. They’ve actually tried it out. I think this is rather sweet, the idea of having a glass of water and inside there are glass beads. Most of them are colourless and some of them are coloured. And what they did was they manoeuvred these little devices around inside that water with magnets, and then once they were in place over the coloured beads they then heated it up and it closed in on those coloured beads, and then if they wanted to they could then take those beads out and separate them out in that way. So I think that’s a rather nice way of showing how it works.

Chris Smith: Very nice for anyone that wants to move around tiny coloured beads in a glass of water but what do they say the actual application of this could be?

Helen Scales: There are surgical applications these devices could be used for. They aren’t there yet really. We’re still kind of developing ways of using these. One thing is that at the moment all they can do is close these boxes; they can’t open them again. Another thing is they are a bit big still. We said they are tiny, they’re under a millimetre, but they’re still way, way bigger than a single human cell. So that if you wanted to actually extract single cells which would be extremely intricate these would have to be even smaller. So that’s maybe the next generation is even tinier micro pincers based on a crab’s claw.

Chris Smith: Let’s hope they’re not shellfish about the things they grab. Thank you, Helen. That was Helen Scales from the Naked Scientists with a roundup of some of this week’s top science news stories. And if you’d like to follow up on any of those items the details and the references are all on the Open University’s website. That’s at

In just a moment, new insights into rheumatoid arthritis, scientists have discovered that the antibodies that attack the joint tissue to trigger the disease are actually produced inside the joints themselves. That’s coming up shortly. But first, have you got the Midas touch? If so, it could be down to hormones and specifically the male hormone, testosterone, but not necessarily now; more when you were a baby inside your mother. John Coates…

John Coates: Well, this study, we didn’t set out with a big question. This study was almost a hazard. We are working on a large research project which involves investigating the role of steroid hormones in the performance of traders and, through that, their effects on financial market instability. We were on a trading floor in London doing the first of several experiments to test this hypothesis.

The main finding of that paper was that when traders had high levels of circulating testosterone in the morning, they made a lot more money for the rest of the day. While doing this research, I read a paper about digit ratios. What they call 2D:4D which is the ratio of your second finger to your fourth finger.

Chris Smith: This is the same ratio that is said to be important in sporting prowess. People who take part in vicious ice hockey matches have much longer fourth fingers than second fingers.

John Coates: Exactly, and for a lark I thought well let’s take hand prints from the traders, which we did and correlated them with their long-term profitability, and we were absolutely astounded at the results because it turned out that their finger ratios were predicting their long-term profitability.

Chris Smith: How do you account for that, to make a horrible financial pun, I know, but what’s actually going on both biochemically and developmentally to mean there is that relationship?

John Coates: Right. That’s the question. We looked into that afterwards. There’s a model in endocrinology according to which there’s sort of two main periods in your life when hormones have a big effect on your behaviour and your development, and that’s during, I think I guess between the 8th and 19th week of gestation there’s a surge of testosterone, and that has organisational effects on the developing body and brain, and then after birth testosterone goes quiescent till puberty. At puberty testosterone comes rushing back into the body and activates all the circuits that it has created back during gestation.

Chris Smith: But how do you account for the difference in the length of the fingers because of testosterone?

John Coates: Well testosterone like most steroids has a wide range of effects on the body. It affects your growth, the shape of your body, your structure of your brain, and it also leaves sort of traces on your body.

Chris Smith: Is there any way of tracking it back and working out exactly why the traders who are like this were exposed to more testosterone in the womb and therefore whether it’s really testosterone or something else which goes along with high testosterone exposure which is making them like this?

John Coates: That’s a very good question and it’s an open question. There’s people on both sides. Some people think that the levels of testosterone actually directly affect finger growth. Other people think that both the amount of testosterone in the foetus and finger growth are determined separately but in parallel by genes.

Chris Smith: But knowing what you do about what goes on on financial markets and the kind of trading that people you were studying were doing and the effects of testosterone, is there an obvious benefit to being very testosterone-charged in that environment?

John Coates: We were studying just a very particular kind of trader. They were called high frequency traders. They take big positions but they hold them for only a few minutes, sometimes even seconds. They have to scan the screens for hours at a time and when they see a small price anomaly, they have to get to it before another trader.

We think that these androgenic traits benefit high frequency trading because it is so close to a form of sports. We’re not sure this correlation would hold up in other types of trading. More importantly, among traders who hold their positions for a very long period of time, like asset managers or hedge fund traders, they might actually have the opposite effect. There you might want higher more feminine digit ratios to succeed.

Chris Smith: And talking of women, I mean I used to work on the Commodity Exchange in London so I’ve been there, there aren’t many of them. And how do you think that plays into this story and do the women that are there, because there are a few, obviously, do they have more masculine-type digit ratios?

John Coates: Well I’d love to be able to extend this sort of research to include women. We haven’t been able to find a trading floor that has a large number of women traders so it’s hard to know for sure. But there’s something about this style of trading that I think is quite unappealing to women.

I have a lot of friends who now run departments in the City, and they say they run floors with like 40 per cent women on them, but of those 40 per cent only a handful would actually be traders. So it’s possible that this style of trading with its sort of high-speed, emphasis on high-speed decision-making just might not be the sort of thing that women prefer. They may be better at long-term positioning of trades.

Chris Smith: And do you think that you’re going to have a whole bunch of companies who put these traders on the floors coming up to you and saying can you draw up some kind of algorithm by which we should appraise potential traders in future based on their morning testosterone and their finger lengths?

John Coates: I’d probably point out something that they already know and that is illegal. I mean you can’t even ask someone their age any more in an interview so I don’t think you’re allowed to sample biomarkers.

Chris Smith: So the bottom line is that next time you talk to your broker, measure his fingers first, ideally, before you threaten to break them. That was John Coates from the Judge Business School at the University of Cambridge, and he’s published those findings in this week’s edition of the journal PNAS.

Now from money changing hands to hands that can really struggle even to pick up a coin. Rheumatoid arthritis is an autoimmune disorder where the body’s own defences turn on our own joints, destroying them and leaving patients sometimes severely disabled. But now scientists in the UK have come a step closer to finding out what it is that causes the body to turn on itself like this. They’ve found that structures similar to lymph nodes, these are the glands that swell up in your neck when you develop a sore throat, actually form inside the joints of patients with rheumatoid arthritis and they produce rogue antibodies that attack the joints from within. Here’s Constantino Pitzalis.

Constantino Pitzalis: Well what we are trying to understand are the mechanisms which lead to joint damage in rheumatoid arthritis. Rheumatoid arthritis is a chronic inflammatory arthritis which affects a large number of people in the world, one per cent of the adult population is affected, and can cost the taxpayer over £1.2 billion a year.

Chris Smith: When someone’s got rheumatoid arthritis, what is actually going on?

Constantino Pitzalis: Well they get pain and swelling of the joints which then continuously causes damage in the joint and functional disability in that the people cannot perform their normal tasks every day like washing and preparing their food and so on.

Chris Smith: But what actually causes that inflammation?

Constantino Pitzalis: What is believed to happen is that there is this function of the immune system. The immune system is an important component of our defence system in the body where the white cells produce antibodies and other mediators which defend normally the body against infective organism or other external invaders. Then when things go wrong and continue to be overactive it can attack parts in the body, and what happens is that these white cells, normally localising in separate sites such as the joints, then attacks the cartilage and the bone causing the joint destruction.

Chris Smith: So what have you done to try and get a more thorough understanding of how this destruction’s actually happening?

Constantino Pitzalis: Well what we have done is to examine in petri dishes and in samples taken from patients, both from the blood and from the lining of the joint, the functionality of the cells which are found there. And what we have discovered is that certain white cells, which are called B cells which produce antibodies, can home to the joint and start forming organised structures called germinal centres which are normally not found in the normal tissues. They are found in lymph glands but not, for example, in the joint. When they home there they can become organised and start producing antibodies. And the importance of these antibodies is they can become very damaging, amplifying the inflammation and causing further joint destruction.

Chris Smith: So was the unknown before you came along with this piece of work that people just didn’t really understand where these antibodies were coming from, where they were getting made?

Constantino Pitzalis: The antibodies are normally produced in lymph glands by the B cells, but what our research has demonstrated is that even within the joint itself these cells have the machinery to produce the antibody. We have identified a specific enzyme which is important for the maturation of antibodies which is present within the joint of these patients and there is a capacity of producing high levels of antibodies.

Chris Smith: So it’s almost like the joints are making the antibody that’s destroying them inside themselves, but how do you know that these structures that you’ve identified are responsible and capable of producing those particular antibodies that do the damage?

Constantino Pitzalis: The way which we approach this was to take the lining of the joint and transplant it under the skin in mice without an immune system so that if the tissues themselves were capable of producing the antibody they would continue to produce into these mice which is actually what happened. Antibodies are produced up to ninety days within these mice. The importance of this research is that it would be possible to test new drugs to inhibit the production of antibodies into the animals, into the mice, before drugs are tested to humans, and that’s very, very important.

Chris Smith: Does this mean then that you will be able to bypass very expensive, very large-scale clinical trials that would be necessary to test these drugs in humans by testing them on the animals?

Constantino Pitzalis: I think it would provide valuable information. Ultimately, still, it would need to be confirmed in patients but the number of patients and the selection of drugs might be greatly helped by having this model to test its drugs.

Chris Smith: So new hope for the treatment of rheumatoid arthritis. That was Constantino Pitzalis. He’s based at Barts in the London School of Medicine, Queen Mary University of London. He’s published that work in this week’s edition of the journal PLoS Medicine.

You’re listening to Breaking Science with me, Chris Smith, and it’s time now for this week’s ‘Stuff and Non-Science’ where we murder urban legends and, not running away from tiresome insects, here’s Diana O’Carroll.

Diana O’Carroll: On ‘Stuff and Non-Science’ this week, I’m swatting those annoying crane flies, otherwise known as daddy long-legs. Stuart Hine is here with the answer this week. Is it a myth that daddy longlegs are the most venomous insects ever?

Stuart Hine: Well definitely a myth, yes. The history, and I guess it’s all in the name, and it’s the name that we commonly call the crane fly in the UK is what we also call the daddy long-legs so it is a true fly with two wings. However, in the United States they have a name daddy longl-egs which is a spider. This is a spider which is also found in the UK. And basically it’s a confusion between these two names.

In the United States, for instance, the daddy long-legs spider has been found to feed on black widow spiders. Given that black widow spiders are terribly venomous, it’s assumed or has been assumed that the daddy long-legs spider must be more venomous than the black widow spider, and I think what’s happened is this story has come over the Atlantic, it reaches the UK and it’s given this common name, the daddy long-legs, that daddy long-legs is a terribly venomous creature, and we think about it in terms of the crane fly, principally, not the spider, and therefore this myth propagated that the crane fly is a terribly venomous creature.

But the adjunct to that story that fortunately it doesn’t have the mouth part to bite us. By now I think we have to question what’s the point of being terribly venomous if you’re not actually doing anything with this venom, and it’s basically a complete and fabricated myth.

Diana O’Carroll: And that was Stuart Hine from The Natural History Museum in London. It’s been a sad year for the tasty crane fly which saw their numbers plummet and those of the birds that safely eat them because of poor weather. But next week we’ll have another savoury bit of non-science, and you can send your own non-science to me,

Chris Smith: So a nice meal of crane fly is just the ticket. Thank you, Diana. That was Diana O’Carroll with this week’s 'Stuff and Non-Science'. That’s it for this time.

We’ll be back next week with another round-up of global science news. Breaking Science is produced in association with the Open University and you can follow up on any of the items in the programme via the OU’s website. That’s at Alternatively, you can follow the links to get there from the BBC Radio 5 Live Up All Night web pages. The production this week was by Diana O’Carroll from the and I’m Chris Smith. Until next time, goodbye.


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These are the sources used by the team in making the show:

In the news

'Psychosocial stress reversibly disrupts prefrontal processing and attentional control'
by C. Liston, B. S. McEwen, and B. J. Casey

'Contribution of Fish to the Marine Inorganic Carbon Cycle'
by R. W. Wilson, et al
in Science

'Tackling Regional Climate Change By Leaf Albedo Bio-geoengineering'
by Andy Ridgwell, et al
in Current Biology

'Tetherless thermobiochemically actuated microgrippers'
by Timothy G. Leong, et al


John Coates on 'Second-to-fourth digit ratio predicts success among high-frequency financial traders', by John M. Coates, Mark Gurnell, and Aldo Rustichin

Constantino Pitzalis on 'Ectopic Lymphoid Structures Support Ongoing Production of Class-Switched Autoantibodies in Rheumatoid Synovium', by Frances Humby, et al. PLoS Med 6(1): e1. doi:10.1371/journal.pmed.0060001

Stuart Hine for 'Stuff and Non-Science'





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