Science Journal

What do foxes and yoghurt have in common? Nothing at all, aside, that is, from that fact that they are the subjects of some interesting experiments in Czech science. Welcome to this month’s Science Journal.

They’ve always said foxes are clever, but now they say they know something that even you don’t. Research done by Czech scientists and published last week in the journal Biology Letters seems to show that the cunning canine has an innate sense of the earth’s magnetic pole - like birds, it knows where north is, and it uses it when hunting. Foxes, they found, are four times more likely to jump north or north-east when hunting, and not only that, they are vastly more successful when they do so, winning their prey 74% or 60% of the time when hunting to the north or south, respectively, and failing miserably at 0-16% of the time when they attack from other directions. And they are not the only mammalian animals with compasses in their heads. The team, led by zoologist Hynek Burda of the University of Duisburg-Essen, made the startlingly simple discovery in 2009 that cattle and deer will instinctively graze to the north, other factors – like weather – allowing. I was wondering, among other things, how they stumbled upon this latest discovery, and I had the chance to ask Dr Burda himself.

“It was just by chance, because since we made this discovery in the deer and the cattle, we always watch animals when we are in the field and check whether they also behave this way. And so it happened to my colleague, Jaroslav Červený, that he was in the forest watching deer and other animals, and he saw a fox hunting mice. Because it was in a familiar area he knew where the north is, and so he noticed that the fox jumped northwards. Then sometime later he saw another fox and it was the same, and so of course he wanted to check it, and so he started observing foxes and the other observations confirmed it. So he asked biologists and hunters to also observe the foxes, and that’s how it started – just by chance, through careful observation.”

“Exactly, that is the biggest challenge. It could be a kind of selective attention. It’s the same thing as when we close our eyes to smell a flower – we try to switch off one sense to increase another. So one hypothesis is that in this position they try to switch off their magnetic sense. The other hypothesis, which was preferred in our article and which reviewers liked more, was that it could work as a targeting system – as a range finder. Actually just last year there was a publication by American colleagues who made a theoretical model that magnetic perception could function not only to measure direction but also to determine distance. And this observation of ours is the first observation from real nature to confirm that that could be. So one explanation that we are favouring at the moment but still have to test, is that in this particular direction – north – the foxes can better determine, better assess, the distance to the prey and know better when to jump and so on.”

So we now know that foxes have compasses ion the heads; it’s interesting, but how else is that knowledge important?

“[laughs] Well you know, it’s always the same of course with all basic research. But if we have found that foxes have this, we have a mammalian model, and we may find that dogs have it, that cats have it, and so on. And that will help us to search for magneto-reception also in humans. And it will help us to assess whether there is indeed some risk caused by electromagnetic fields and so on. Because questions of the health risks of electromagnetic fields, high-voltage power lines for example, is always being discussed, but as long as we don’t know whether there is some seat of magneto-reception, and whether or not it is in humans, and how it make work, then it’s all just a question of epidemiological statistics; some say yes, there is a hazard, others say no. But maybe this discovery can help us to find how magneto-reception in mammals functions, and in that case we can also test it in humans and will have better possibilities for assessing such hazards and determining eventually whether there are risks or not.”

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If you’re a student preparing for exams you should listen up. Eat yoghurt. Your white blood cell count is steadily diminishing. That may not be why you feel hung-over, but it is adding to your stress levels and weakening your immunity and overall heartiness. The antidote is probiotic bacteria. So says Dr Petr Petr of the University of South Bohemia and a group of researchers monitoring dozens of yoghurt-eating and non-yoghurt-eating students for a period of 33 days. Earlier this week I called Dr Petr to talk about all things yoghurt. What does he hope to learn from his experiment, when the healthiness of yoghurt has been known for a long time?

“You’re right, since 1903, from Élie Metchnikoff’s pioneering work. But almost nobody is trying to reconfirm the data under the conditions of academic stress. We are trying to prevent the diminishment of the white blood count through this type of intervention under the condition of academic mental stress, because the examination period is the standard model of mental stress.”

How do Czechs weigh in in terms of yoghurt consumption compared with the rest of the world?

“Oh we have very poor figures for Czechs as a nation. In general, the consumption of fish and dairy products is very low in this country, and indirectly what we are hoping to do is influence the habits of Czechs through research like this.”

We spoke earlier today already and you mentioned the Zulus and their consumption of yoghurt…

“That’s a surprising story from Duke University in North Carolina going around the world, that the Zulus in South Africa are famous for consuming large amounts of fermented milk called ‘amase’ locally, and luckily enough I have been given the possibility of looking into the situation on the spot, there in South Africa. It is possible that the strength of Zulus as warriors is also based on the regular consumption of yoghurt.”

But even elsewhere in Europe various kinds of milk and yoghurt specialities are consumed…

Dr Petr Petr

“Yes, in the Balkans. In southern Bulgaria, for example, the native population consumes huge amounts of yoghurt daily, and the longevity among this population is probably based on that consumption. “

So why do Czechs tend to not consume much yoghurt, in your opinion?

“There is no single explanation in my view, but this is a very industrialised society. In the heart of the Czech Lands, when you compare it with Slovakia or the Balkans, there is almost no domestic farming for family consumption. There are almost no small family farms nowadays, so the dietary habits of our population are far, far from those of older days, or in the Balkans.

Dr Petr Petr, who will hopefully soon be bringing the secrets of ancient Zulu warrior wisdom to Czechs low on probiotic bacteria. That’s all the experimentation we have time for this month, tune in again in February for all the news that’s fit to put to scientific scrutiny.