Morphogenesis

The development of spatial structure in the embryo has been found to involve a chemical reaction that is analogous to standing waves.[i] Using a staining technique, morphogenesis can be seen in the early embryo, in the form of a periodic banded pattern. This pattern indicates alternating concentrations of morphogens, which chemically mark the tissue, identifying which cells belong together. The mechanism, known as reaction diffusion, involves a continuous process whereby morphogen P catalyses the production of more morphogen P, plus morphogen S, which inhibits morphogen P. The physiological development of the organism is thus marked out, distinguishing bones, muscles, internal organs, etc. Camouflage patterns have also been attributed to reaction diffusion.[ii] The stripes of the zebra and the spots of the leopard show how morphogenesis exploits periodicity for evolutionary advantage. The extent to which this process is analogous to standing waves is easily appreciated when comparing patterns of animal skin colouration and sand vibrating on a steel plate. The sand accumulates at the nodes of vibration, to reveal the geometric character of the harmonic resonance. Many patterns found in living organisms can be replicated in this way.

The underlying argument is that the evolution of biological form is founded on generic physical forces, which presumably served as morphological templates within which genetic selection could operate. While the similarity between so many physical and organic forms suggests such a connection, the case is rather more compelling if one considers that many organisms have morphological features that are similar to physical forms despite being genetically unrelated. For example, a 3D logarithmic spiral found in seashells is also evident in tidal-washed kelp fronds and in the shape of our own skin pores.[iii]

Natural patterns and processes are often applied to the development of new technology. This approach to design, called Biomimicry, enables designers to take advantage of the millions of years of incremental variations that have been made through biological evolution, to gain insight into the underlying principles determining naturally evolved shapes. For example, a highly efficient fan blade has been designed using the 3D logarithmic spiral, common throughout the natural world, because this shape optimises the flow of water or gas across its surfaces.[iv]

As with naturally evolved shapes, the activity of design draws on the spatio-temporal structure of Being, to produce something new that extends the experience of Being.[v] On this basis, the surfboard designer’s ability to invoke the link between spatial and temporal relations validates the surfing metaphor as a tool for visualising the spatio-temporal structure of experience.

Next chapter: Intellect.

References

[i] Lehar, S. (2003). Harmonic Resonance Theory: An alternative to the “Neuron Doctrine” paradigm of neurocomputation to address gestalt properties of perception. The Behavioral and Brain Sciences, 26 (4), p.15.

“The utility of standing wave patterns as a representation of spatial form is demonstrated by the fact that nature makes use of a resonance representation in another unrelated aspect of biological function, that of embryological morphogenesis, or the development of spatial structure in the embryo.”

[ii] Ibid.

“After the initial cell divisions following fertilization, the embryo develops into an ellipsoid of essentially undifferentiated tissue. Then, at some critical point a periodic banded pattern is seen to emerge as revealed by appropriate staining techniques, shown in figure 3A. This pattern indicates an alternating pattern of concentration of morphogens, i.e. chemicals that permanently mark the underlying tissue for future development. This pattern is sustained despite the fact that the morphogens are free to diffuse through the embryo. The mechanism behind the emergence of this periodic pattern is a chemical harmonic resonance known as reaction diffusion (Turing 1952, Prigogine & Nicolis 1967, Winfree 1974, Welsh et al. 1983) in which a continuous chemical reaction involving a morphogen P catalyzes the production of more morphogen P as well as of a morphogen S, but the concentration of morphogen S in turn inhibits production of morphogen P (see Gilbert 1988 pp 655-661 for a summary).”

[iii] Pronk, A.D.C., Blacha, M. & Bots, A. (2008). Nature’s Experiences for Building Technology, p.4.

[iv] Ibid.

“Example of use of the pattern found in snail-shells, like the mollusk shells are the fans, propellers, impellers, and aerators designed by PAX Scientific (USA), see [1]. A three-dimensional logarithmic spiral is found in the shells of mollusks, in the spiraling of tidal-washed kelp fronds, and in the shape of our own skin pores, through which water vapor escapes. Liquids and gases flow centripetally through these geometrically consistent flow forms with far less friction and more efficiency.”

[v] Palmer, K. (2006). On the Ontology of Emergent Design and General Schemas Theory: Research into The Deep Structure of Design, p.1.

“Dasein reacts to what has Being and produces something new, which extends and expands on what Being covers. In other words what Being covers is changed by the activity of Design.”

 

 

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