Vincent Fleury On Origin Of Form (And PZ Myers)

Article – Suzan Mazur

Vincent Fleury is a French scientist investigating origin of form with experiments involving cellular flow. He was recently featured in a PZ Myers Pharyngula blog — where his work first caught my eye.

Vincent Fleury On Origin Of Form (And PZ Myers)

By Suzan Mazur

Vincent Fleury

Vincent Fleury is a French scientist investigating origin of form with experiments involving cellular flow. He was recently featured in a PZ Myers Pharyngula blog — where his work first caught my eye.

Born in 1963, Vincent Fleury lived for eight years in Uruguay before returning to France with his family. He completed a PhD at the Ecole Polytechnique in pattern formation in electrochemical growth and then began to focus on biological systems, studying the development of blood vessels and the lungs. Fleury says he’s long advocated the role of physical forces in development, apparent in blood vessels and in the lungs.

Fleury has proposed a biomechanical model of tetrapod formation by extending the concepts of cellular flow to the formation of the embryo as a whole. He says that “once the formation of the body of a tetrapod is boiled down to a simple physical field, different animals appear as different instances of a similar process, thus explaining obvious tendencies in evolution, and maybe the very origin of these animals.”

Vincent Fleury is the author of four popular science books: Arbres de pierres, Des pieds et des mains, De l’oeuf a l’eternite, La chose humaine, and under a pseudonym, six detective novels (four for adults and two for children).

My recent phone conversation with Vincent Fleury follows:

Suzan Mazur: Would you say there’s more than a language barrier when it comes to French and American thinking about evolution?

Vincent Fleury: That is a complex question. Yes. There is more than a language barrier regarding evolutionary science. American and British, i.e., Anglo-Saxon thinking is in terms of efficiency. The way Americans work, everything should work, everything is extremely pragmatic. Everybody on the team has a little bit of a job to do.

The consequence of that thinking is that Darwinism fits in very well. The animal works. It does the job it has to do. And it survives.

In general terms, French people are more Cartesian. We have a more philosophical way of thinking. We try to find deep concepts.

Suzan Mazur: What would you say the significance is of recent discussions at the Sorbonne on evolutionary mechanisms and of the Jean-Baptiste Lamarck conference in Israel?

Vincent Fleury: I was invited to such a conference at Versailles about two years ago.

Maybe there’s some kind of nervous breakdown among scientists, especially with a significant number of biologists who are exhausted and truly don’t understand what they are doing. Some of them wonder whether it’s science at all. They keep piling up facts about genes and chemicals but don’t have a satisfactory scheme.

Suzan Mazur: PZ Myers, the Howard Stern of sciencebloggers, recently reviewed your paper Clarifying tetrapod embryogenesis, a physicist’s point of view, which was published in The European Physical Journal: Applied Physics. It appears Myers is increasingly doing a pas de deux with the physical approach to evolutionary science, trying to reposition himself now that a paradigm shift is afoot. In essence, so he can maybe say, well I knew it all the time.

Last week he praised D’Arcy Thompson and Brian Goodwin, saying he found Goodwin’s work “thought-provoking”. What is your response to Myers tactics?

Vincent Fleury: I have mixed feelings. On the one hand he’s trying to promote good science and bring back people who are lost in creationism. The problem is…

Suzan Mazur: Do you agree he’s trying to reposition himself?

Vincent Fleury: Well that’s fine. But I have a problem with this fellow. He uses a very rhetorical technique. He starts off with some smooth positive statement and then progressively trashes the paper. I’m not so sure it s sincere.

Suzan Mazur: It’s his way of saying I love you. He knows he can’t maintain his present ground, so he’s increasingly introducing the newer evolutionary science, however he can. He projects himself as a bully so he won’t look like a sissy when he has no choice but to go with the flow.

Vincent Fleury: There are several issues. First of all, it’s the style of the man. When you read his blog, you read things like I’m a professor and if I had a student, I would have asked him to rewrite the paper in this and that way. Who is this man?

Suzan Mazur: Think Animal House and pimply adolescence. His audience, incidentally, includes some prominent evolutionary scientists — one of whom commented on your paper in the Pharyngula blog.

Vincent Fleury: Myers’ blog is constructed in a certain way. He writes reviews that are not that bad but then he opens it up to his hounds, half of whom are mad. Crazed! They finish the job.

Freedom of speech is one thing, but it is extremely insane to open the microphone to crazy people.

Suzan Mazur: Why was your paper sent to Pharyngula?

Vincent Fleury: Someone else sent the paper in to harass me. Myers says implicitly that he despises all these self-organization ideas, but if you look at his blog, his web site is a an example of self-organization.

Suzan Mazur: How have your colleagues at CNRS (French National Center for Scientific Research) responded to his attack?

Vincent Fleury: Who cares? The few who know of him in France understand it’s rubbish.

Suzan Mazur: You’ve commented that PZ Myers doesn’t know how the human body is established.

Vincent Fleury: Well that’s true. He doesn’t.

It’s been known for almost 100 years that the initial spherical oocyte becomes a spherical blastula. When it starts to resemble an animal, that happens by the third day in a chicken, it’s by a vortex motion. It’s a pattern of eddies. Little swirling movements.

You have vortices, like wind turning around, that transform the spherical thing into an elongated thing with two bumps in the hip region and two bumps in the shoulder region. So these are vortices.

Suzan Mazur: You’ve said it is a hyperbolic flow that transforms a round blastula into an embryo.

Vincent Fleury: How do animals acquire their form? You have a reference for it, the sphere. Oocytes are more or less spherical.

A couple of days after, you have an animal which is roughly recognizable. In the third day of the development of a chicken you already recognize the typical shape. It’s very rapid. It lasts about 15 hours. That specific movement transforms a sphere into something resembling an animal.

What is that? It’s a vortex flow. It’s composed of four vortices revolving around a stagnation point. And that’s a hyperbolic flow.

Suzan Mazur: What about the criticism that this may be too simple an approach.

Vincent Fleury: It’s not too simple. The problem is that for a century or so these vortices have escaped the attention of biologists. It’s not something that you can address with the biology techniques and concepts. However, today we can watch this with time-lapse microscopy, etc. People have recorded these vortices. There are actual movies of this.

I first made the theory about this. It had never been done before. It contains a lot of physics.

Suzan Mazur: So the hyperbolic flow can in essence be the origin of all form.

Vincent Fleury: Yes it’s the archetype. In Darwin’s book, chapter 13, there is a description of archetypes. He states there are four archetypes of animals. One of the archetypes is the tetrapods. He says that for whatever purpose they have limbs, etc. and that I don t know what the origin of the first archetype is, but afterwards all the animals may be obtained simply from the same archetype by stretching or flattening. That’s explicitly stated in Darwin’s book.

Suzan Mazur: And does the torus concept have any bearing on this?

Vincent Fleury: Maybe there is some torus inside the oocyte or in the first cell before the first cleavage that could be at the root of the phenomenon I don t know. What I do know is that if you take the first two cleavages when it’s basically crossed inside the first four blastomeres and you extrapolate the blastula and then you start the flow, it starts to move. With that initial big cross inside, you make a tetrapod. It’s completely automatic. It’s the attractor of the flow. It takes just a few hours.

Next, the only thing you can do is stretch the animal in six directions. The head, the tail and the limbs. All animals are obtained from the basic form by stretching the limbs, the neck or the tail.

Suzan Mazur: You talk about the deformation rate field. Can you explain what that is?

Vincent Fleury: When you start with a certain form, say spherical – 10 hours later you have a little fish. You have to deform the thing during a certain time. And this is what is called in physics a deformation rate, or strain rate. The deformation rate for an inflated balloon, for instance, is the speed of inflation.

Suzan Mazur: And you said you had the equation to deform an embryo to make a mouse and various other animals. To go from a lizard to a snake, from ape to human. Would you address that?

Vincent Fleury: When you deal with a physics problem, you try to have a simple mechanism that explains it all, so to speak, but that you can refine to any specifics. So when you look at the blastula you realize that it’s a hyperbolic flow. The hyperbolic flow has an extraordinary property. A major property. There is a point where the speed is zero in all directions. And this point represents the navel, the belly button.

So the very origin of our belly button is the fact that in the blastula, there is a zero point where the speed is zero in all directions. This is a fact. I’m not speaking of something hypothetical. You can observe it.

In mathematics when you have a point where the quantity that you are studying equals zero, then you can do a mathematical expansion of the problem around zero. And when you do that, you can show that with the hyperbolic flow — the first step is the hyperbolic flow — there is a contraction in the lateral direction and expansion in the head-tail direction. So the first tendency mathematically speaking of this flow is to transform a sphere into an elongated elipsoid. This is typically the transition of all animals which are more or less squarish.

In the direction of evolution you find more elongated animals. But it doesn’t mean there is a gene of elongation. There is no gene of elongation. It means that within the dynamics of the system, it is wired. Whatever gene you change, you make an animal which is more squarish or more elongated. It’s very simple. It’s one dimension. One degree of freedom around the belly button. This is why animals tend to be squarish around the belly button as is da Vinci’s “Vitruvian Man”, which bears the caption: “The true center of the human being is the navel.”

Or if you start to make more elongated animals, they will look like anguids or like snakes. In evolution, snakes result from a prolonged hyperbolic flow. It’s automatic. That ‘s the first order.

Now the second order is the twist of the tissue in each quadrant of the hyperbolic flow, which generates the position of the limbs. And depending on whether this twist is more or less twisted, you have an animal with a pelvis that is more or less warped and shoulders that are more or less warped. So you get an animal that is more like a kangaroo or more like a mouse.

Suzan Mazur: Your PhD is in physics pattern formation and crystal growth, is that correct?

Vincent Fleury: Electrochemical deposition and pattern formation.

Suzan Mazur: Would you explain how crystals come into the evolution picture? How do they come into the biology?

Vincent Fleury: It’s very well understood how a crystal grows. A lot of very beautiful mathematics have been developed over 250 years. A French man, Hauy, is the one who first invented crystallography and discovered that atoms were regularly ordered in crystals. At that time they were not sure that atoms existed, but Hauy understood that crystals were made of ordered elements.

The beautiful thing about crystals is that you see in the global shapes the property of the microscopic texture. You can recognize in the global shape the property of microscopic organization. That suggests two things. Forms appear by physics of moving boundaries and the fact that a small feature has an influence on the larger scale. And these two facts, I think, are really at the root of the development of the physics of evolution and of animal development right now.

Suzan Mazur: Antonio Lima-de-Faria, the University of Lund cytogeneticist, has been talking about things like this for many years as well. He says The biological and crystal levels are now found to have several common atomic parameters .

Vincent Fleury: In one of my papers regarding an equation for crystal growth I found a way of applying it to the growth of fruit and vegetables. You can show that lemons, for instance, or other fruit are some sort of crystals. They are not crystals of atoms, they are crystals of fibers.

Quartz, diamond, etc., their microscopic texture is made of organized atoms. The same physics with a slightly different input (fibers instead of atoms) gives you different shapes, and this is why biological shapes are not quite like crystal shapes but they share the same organizing principles.

Suzan Mazur: Here’s what Lima-de-Faria says: “The gene is only the bearer and the carrier, of the atomic order that already determined mineral symmetries. Moreover, due to the occurrence of molecular mimicry an organism may not even need to have the same genes to produce the same structural pattern.”

Vincent Fleury: Absolutely. That s a central point in my paper. In fact, the number of shapes which are produced by the physical laws are very limited. And in fact a huge quantity of genes will apply or project themselves on the same shapes.

If you look at dwarfism, there exists a hundred kinds of dwarfism associated with completely different genetic anomalies. But the consequence is the same thing. A condition, a morphology you call dwarfism. But it has a completely different origin. Because in fact you can change lots of genes, the consequence is basically the same. So in fact, it reduces considerably the number of outputs.

So for example, you can make an elongated animal from a squarish one in a completely different way. You have fish that are somewhat squarish and fish that are very elongated. It s the same mechanism for lizards becoming snakes. There is not a gene for an elongated animal.

Suzan Mazur: Scientists in America tend to be conservative about these subjects.

Vincent Fleury: In America you have big scientific teams with a lot of money, so the principal investigator has a heavy responsibility. In France and other countries in Europe we have less money and more individuals working in very small groups one or two people. So they do things which are newer or more original. They don t have the need to prove to their staff that what they are doing is safe.

Suzan Mazur: Here, to get funding from the government, scientists have to agree to ensure national security and the economic well-being of the country. You’re a French government scientist you don t have similar constraints?

Vincent Fleury: A few years ago we had more freedom. Now they’re looking more to the American model of efficiency. We fill out a file in which we more or less explain what will be the results of our experiments, ahead of doing them.

Suzan Mazur: The cost-effective approach.

Vincent Fleury: One last thing about PZ Myers. He made the following comment on his blog regarding my right of reply, instead of just publishing it: “I’m always happy to help a fellow hang himself.”

Even if he s trying to make a joke, we all know people who’ve committed suicide, and I would never entrust my children to a babysitter who states he is always happy to help someone hang himself.


Suzan Mazur is the author of Altenberg 16: An Exposé of the Evolution Industry. Her interest in evolution began with a flight from Nairobi into Olduvai Gorge to interview the late paleoanthropologist Mary Leakey. Because of ideological struggles, the Kenyan-Tanzanian border was closed, and Leakey was the only reason authorities in Dar es Salaam agreed to give landing clearance. The meeting followed discovery by Leakey and her team of the 3.6 million-year-old hominid footprints at Laetoli. Suzan Mazur’s reports have since appeared in the Financial Times, The Economist, Forbes, Newsday, Philadelphia Inquirer, Archaeology, Connoisseur, Omni and others, as well as on PBS, CBC and MBC. She has been a guest on McLaughlin, Charlie Rose and various Fox Television News programs. Email: sznmzr @

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