Alan Turing's 1950s tiger stripe theory proved

Feb 19, 2012
Image: Wikipedia.

Researchers from King's College London have provided the first experimental evidence confirming a great British mathematician's theory of how biological patterns such as tiger stripes or leopard spots are formed.

The study, funded by the Medical Research Council and to be published online in , not only demonstrates a mechanism which is likely to be widely relevant in vertebrate development, but also provides confidence that chemicals called morphogens, which control these patterns, can be used in regenerative medicine to differentiate stem cells into tissue.

The findings provide evidence to support a theory first suggested in the 1950s by famous code-breaker and mathematician Alan Turing, whose centenary falls this year. He put forward the idea that regular in are generated by a pair of morphogens that work together as an 'activator' and 'inhibitor'.

To test the theory the researchers studied the development of the regularly spaced ridges found in the roof of the mouth in mice. Carrying out experiments in , the team identified the pair of morphogens working together to influence where each ridge will be formed. These chemicals controlled each other's expression, activating and inhibiting production and therefore controlling the generation of the ridge pattern.

The researchers were able to identify the specific morphogens involved in this process – FGF (Fibroblast Growth Factor) and Shh (Sonic Hedgehog – so-called because laboratory fruit flies lacking the fly version have extra bristles on their bodies). They showed that when these morphogens' activity is increased or decreased, the pattern of the ridges in the mouth palate are affected in ways predicted by Turing's equations. For the first time the actual morphogens involved in this process have been identified and the team were able to see exactly the effects predicted by Turing's 60-year-old speculative theory.

Dr Jeremy Green from the Department of Craniofacial Development at King's Dental Institute said: 'Regularly spaced structures, from vertebrae and hair follicles to the stripes on a tiger or zebrafish, are a fundamental motif in biology. There are several theories about how patterns in nature are formed, but until now there was only circumstantial evidence for Turing's mechanism. Our study provides the first experimental identification of an activator-inhibitor system at work in the generation of stripes – in this case, in the ridges of the mouth palate.

'Although important in feeling and tasting food, ridges in the mouth are not of great medical significance. However, they have proven extremely valuable here in validating an old theory of the activator-inhibitor model first put forward by Alan Turing in the 50s.

'Not only does this show us how patterns such as stripes are formed, but it provides confidence that these morphogens (chemicals) can be used in future regenerative medicine to regenerate structure and pattern when differentiating into other tissues.

'As this year marks Turing's centenary, it is a fitting tribute to this great mathematician and computer scientist that we should now be able to prove that his theory was right all along!'

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Going
3.4 / 5 (21) Feb 19, 2012
Science does not "Prove" things as you state in your headline. A hypothesis survives a test and remains a good theory or even our best theory. Nothing has ever been proved in the history of science. Please read up on Popper.
Crazy_council
4.6 / 5 (25) Feb 19, 2012
such a shame the way we treated this man, whar might have he discovered if we would have supported him.
LuckyBrandon
1.8 / 5 (16) Feb 19, 2012
While I agree there could be speculation, I would have to beg to differ on science never proving anything. The fact you are typing or reading on here is proof positive that it DOES prove things, and even more, does things with those things it proves.
So unless we are all in the stone age, I would say you are incorrect.

wait come to think of it, even in the stone age science solved problems, we just didnt call it science yet...
Eikka
4.6 / 5 (18) Feb 19, 2012
The fact you are typing or reading on here is proof positive that it DOES prove things, and even more, does things with those things it proves.


Nikola Tesla didn't believe in atoms or electrons, yet he invented the three phase power system based on a hypothesis on electrical fluids that was patently wrong, yet produced applicable results. Analogs work, but they always fail at some point.

You can explain a computer with magic and still produce meaningful results as long as your magic book contains the right ideas on how to make a working transistor.
RealScience
4.6 / 5 (9) Feb 19, 2012
@Going - ignore the headlines - they are usually written by non-scientists.

The article itself says:
The findings provide evidence to support a theory...
Callippo
Feb 19, 2012
This comment has been removed by a moderator.
bewertow
3.2 / 5 (13) Feb 19, 2012
such a shame the way we treated this man, whar might have he discovered if we would have supported him.
Apparently it doesn't apply to aether theory...;-)


Reported for aether spam. Since you clearly can't read, this is an article about Alan Turing's theory.
bewertow
1.9 / 5 (9) Feb 19, 2012
such a shame the way we treated this man, whar might have he discovered if we would have supported him.
Apparently it doesn't apply to aether theory...;-)


Also, I think it is insulting to Alan Turing's memory that you dare to consider yourself on the same level as him.
Martin_Forde
4 / 5 (13) Feb 19, 2012
Science does not "Prove" things as you state in your headline. A hypothesis survives a test and remains a good theory or even our best theory. Nothing has ever been proved in the history of science. Please read up on Popper.


You should read more yourself. Science uses inferential statistics, whereas Popper is talking about logical inferences: both of which entail different epistemologies. For instance, falsification is non-sensical in terms of inferential statistics. If we accept a null-hypothesis, then we are doing so off of a specific probability value (P). In turn, the probability of making a type 2 error is 1-P, i.e., not 0%. Consequently, in a strict sense, logical falsificationism isn't even applicable to science.
davazi
1 / 5 (1) Feb 20, 2012
Science does not "Prove" things as you state in your headline. A hypothesis survives a test and remains a good theory or even our best theory. Nothing has ever been proved in the history of science. Please read up on Popper.

I am quite interested in what you said. Could you recommend some books on this topic? Thanks a lot.
You should read more yourself. Science uses inferential statistics, whereas Popper is talking about logical inferences: both of which entail different epistemologies. For instance, falsification is non-sensical in terms of inferential statistics. If we accept a null-hypothesis, then we are doing so off of a specific probability value (P). In turn, the probability of making a type 2 error is 1-P, i.e., not 0%. Consequently, in a strict sense, logical falsificationism isn't even applicable to science.

Anastaziel
1 / 5 (1) Feb 20, 2012
@Going I was going to say how wrong you are but Martin Forge already did that for me. I wish people would stop confusing what they learned during their "Logic" and/or "Statistics" courses they took in their Bachelor/Master in Political "Sciences" (or another similar) degree with hard science.

Biological organisms work according to mathematically expressible equations and in mathematics you do have the ability to prove a hypothesis.

Falsification is the only form of assertion does not apply to mathematics.
Kinedryl
1 / 5 (2) Feb 20, 2012
Also, I think it is insulting to Alan Turing's memory that you dare to consider yourself on the same level as him.

Also, I think you would handle Alan Turing in the same way, like me, if you would be his contemporary. But what we are thinking is irrelevant, the real actions is what matters here.
visual
not rated yet Feb 20, 2012
Does anyone actually understand Turing's theory about this subject, and is it possible to summarise it in some easy to understand form? Or give references for further studying?

Just saying "activators and inhibitors do it" explains nothing at all. In partcular, how do these (entirely in-cell?) activators and inhibitors give a result that depends on the spatial position of the cell in relation to other cells in the tissue?
moj85
5 / 5 (3) Feb 20, 2012
Visual: Morphogens are literally just anything that causes an effect on tissue growth/development. In general, they work because of concentration differences that occur during development. In this case, FGF and Shh are two of the morphogens (proteins) that, in varying concentration, causes different phenotype in the organism (tigers). Think of a color gradient from Black, to grey, to white (http://www.adobe....ient.jpg is a good example of a gradient.. think of the colors as concentration of the morphogen)
apostrophe
1 / 5 (1) Feb 20, 2012
Are mathmatical or science proofs a fleeting thing? I think maybe. Although I steer far from the near religious application that "Nothing has ever been proved in the history of science", I do imagine that existent proofs may not survive the tests of time and space...but then neither shall we.
Anda
1 / 5 (1) Feb 20, 2012
Hey Rawa, just bite an apple and ...
Deathclock
4 / 5 (4) Feb 20, 2012
Proof in general does not exist.

You can only "prove" things relative to a context defined by initial assumptions.

"Proving" something is relegated to the domain of the following statement "If a, b, and c are true, then d is true", the problem is, you then have to "prove" a, b, and c... and the only way to do that is to say "If x, y, and z are true then a is true"... you cannot ever get away from the initial assumptions, because at the final level the initial assumption is "If my perception of reality is not a complete illusion then..." and there is no way to prove that your perception of reality is not an illusion.
Going
1 / 5 (1) Feb 21, 2012
Science does not "Prove" things as you state in your headline. A hypothesis survives a test and remains a good theory or even our best theory. Nothing has ever been proved in the history of science. Please read up on Popper.


Read "The Fabric of Reality" (1997) by Oxford professor David Deutsch for an explanation of how knowledge is created, what can be known and what can't be known.
antialias_physorg
2.6 / 5 (5) Feb 24, 2012
Are mathmatical or science proofs a fleeting thing? I think maybe.

Mathematical proofs aren't. Scientific proofs are.

Though there is, strictly speaking, no such thing as a scientific proof. There is, however, such a thing as a currently scientific best model.
But you can show that there is ALWAYS (theoretically) a better model to be had than the current one - with the best 'model' being the universe itself (it - and it alone - fully and accurately represents what it is).

The thing about models is: They are a tradeoff between simplicity and accuracy. While the universe as a model of itself may be very (ultimately) accurate it is also not a model that is simple to use.

What science strives for is to get best models that encompass a lot of what the universe seems to be like - while retaining greatest possible simplicity.

E.g. relativity, quantum mechanics and electrodynamics do a very good job at trading miniscule inaccuracy for enormous ease of use.
CardacianNeverid
4 / 5 (4) Feb 24, 2012
Sorry, meant to give AntiAlias a 5!
antialias_physorg
3 / 5 (2) Feb 24, 2012
Don't worry, I've survived worse ;-)

There's a guy who regularly stalks me to downvote anything I say. To date it hasn't had any effect on the average rating.
Going
not rated yet Feb 25, 2012
Sorry, meant to give AntiAlias a 5!

I have given you 5. A very clear explanation.
LuckyBrandon
1 / 5 (1) Mar 09, 2012
Nikola Tesla didn't believe in atoms or electrons, yet he invented the three phase power system based on a hypothesis on electrical fluids that was patently wrong, yet produced applicable results. Analogs work, but they always fail at some point.

You can explain a computer with magic and still produce meaningful results as long as your magic book contains the right ideas on how to make a working transistor.


Yea but the science gives you the capability to see how its really working. No magic necessary. That's my point.
Paul_Duncan
not rated yet Mar 09, 2012
Proof in general does not exist.


In terms of trying to mathematically prove something, sure. Can't do it. However proof is all around us in a natural form, even if this is an illusion, it is whatever it is. Science is simply a measurement system to try and get as exact as possible to whatever 'it is'.