Nature’s ability to create intricate patterns, like those on fish skin or zebra stripes, has long fascinated scientists and laypeople alike. Dubbed Turing patterns after the mathematician and computer scientist Alan Turing who first studied the phenomenon, they aren’t just aesthetically pleasing; they also play vital roles in animal behavior and ecosystem dynamics, such as camouflage and mate attraction, impacting everything from predator-prey interactions to population dynamics. The physics behind these patterns may also help us to decipher a universal language of pattern formation that can be applied across multiple scientific disciplines.
Past research has suggested that Turing patterns form due to the chemical reaction-diffusion process, where some chemical agents diffuse and react with each other while others inhibit the spread, leading to the spaces between spots. However, this theory fails to explain the striking sharpness of these natural patterns. A recent study on the ornate boxfish adds a new dimension to this picture – diffusiophoresis, which is the movement of particles in response to a concentration gradient. In this case, chromatophores (specialized pigment cells) respond diffusiophoretically to physiological reactions, creating a robust patterning of cells with fine details. By incorporating diffusiophoresis into simulated Turing models, the researchers demonstrated that they could recover the steepness and clarity of patterns in nature.
This study not only provides a more comprehensive understanding of pattern formation, but also unveils the importance of diffusiophoresis. This phenomenon may have an important role in other biological processes too, such as the formation of embryos and tumors. These findings also have implications for various fields, from materials science to biotechnology; possible applications include precise microscale patterning for biomaterial design and cancer treatment.
This study was led by Benjamin M. Alessio, a research assistant, and Ankur Gupta, an Assistant Professor, both in the Department of Chemical and Biological Engineering at University of Colorado Boulder.
Managing Correspondent: Rosella (Qian-Ze) Zhu
Press Article: A new study updates Turing’s theory on how animals get their spots and stripes (CNN)
Original Journal Article: Diffusiophoresis-enhanced Turing patterns (Science Advances)
Image Credit: Unsplash/David Clode
Ah, how many “patterns” we saw in neuroscience that led to dogmas that later had to be abandoned! One need only think back to what one “sees” as an obvious pattern in childhood, only to have so many changes in one’s “seeing” of it when the brain in enriched with so many more activated and inactivated synapses through a life full of other unrelated experiences. As one goes from artist painting a sight to scientist tracing activated neuronal tracts, one invariable recognizes that, where alone or en masse, what is “seen” is presumptive. Science is thus IMPRESSIONISTIC, as a working hypothesis, only to become after long study MECHANISTIC through the molecular elucidations of repeatedly proven processes. An experiment need only deviate 2 SDs phenomenologically before it’s back to the drawing board. But once the collective work of its parts is fully known and ordered into a mechanism does it trully become a mechanistic basis of science, namely the application of reliable qualitative AND quantitative laws that under similar situations ONLY come out reliably as the experiment is ever repeated, demonstrating ever repeated basic mechanistic rules elucidated based on universally accepted principles. Whether it is UFOs or the Webb Telescope forcing us to review our mathematical “givens,” the distinction between impressionistic and mechanistic will always stand as the gap that has to be startled before one can comfortably say, “Ah! Now I REALLY understand!!!” Lastly, let us not forget the brain’s most perennial foe, RANDOMNESS. It has learned to lie to itself rather than accept it. How many times does one need to sense processes repeating before one can be sure? Mathematics is not an accounting of reality but rather and impression of our neuronal crowd sourcing. through active inhibition of ever shaped activation. And then, that too may prove to be a gross mirage conjured up by synaptic deceptions. I still regard great and aw inspiring computations as mirage until tied into a knot by ever more such repeated observations. Until then, it’s all a very, very nice clever explanation. But then, I always wonder how creative chimps would seem if they could write prose or equations. But, nevertheless, I’m always there cheering in amazement and delight at the Nobel Prize Lectures, despite my perspiring underarms SUGGESTING that I am nervously wondering: “What if someday someone proved all wonderful research of PATTERNS as Processes all wrong. That’s why I still hang on to my every edition of genetics and Molecular Biology books. The more they sound alike, the more I feel proud of Homo sapiens. So onward, onward my brave colleagues for it’s all in the journey, not in the arrival!