Still More Excuses for Cambrian Non-Evolution
Evolution News | @DiscoveryCSC
Physical Foundations of Biological Complexity
Evolution News | @DiscoveryCSC
Physical Foundations of Biological Complexity
A non-typical, out-of-the-box thinker, Eugene Koonin is often fun to read, at least compared to the typical Darwin apologist. With two co-authors in PNAS last month, the evolutionary biologist set out to explore “The Foundations of Biological Complexity.” His topic is broader than the Cambrian explosion, but entails it.
Living organisms are characterized by a degree of hierarchical complexity that appears to be inaccessible to even the most complex inanimate objects. Routes and patterns of the evolution of complexity are poorly understood. We propose a general conceptual framework for emergence of complexity through competing interactions and frustrated states similar to those that yield patterns in striped glasses and cause self-organized criticality. We show that biological evolution is replete with competing interactions and frustration that, in particular, drive major transitions in evolution. The key distinction between biological and nonbiological systems seems to be the existence of long-term digital memory and phenotype-to-genotype feedback in living matter.
Design advocates may wish to look more deeply into Koonin’s paper, but after you simplify the jargon and restate the basic ideas, he seems to be saying that biological matter is just a special case of non-biological matter with memory. As for “competing interactions and frustration,” is that like squeezing long balloons so that a dog shape pops out? Surely there must be more to the “emergence of complexity” than this! Even if the long balloon can remember what happened in the previous “frustrated” state, you won’t get trilobites this way.
Biological systems reach hierarchical complexity that has no counterpart outside the realm of biology. Undoubtedly, biological entities obey the fundamental physical laws. Can today’s physics provide an explanatory framework for understanding the evolution of biological complexity? We argue that the physical foundation for understanding the origin and evolution of complexity can be gleaned at the interface between the theory of frustrated states resulting in pattern formation in glass-like media and the theory of self-organized criticality (SOC) .… We unify these two faces of SOC by showing that emergence of complex features in biological evolution typically, if not always, is triggered by frustration that is caused by competing interactions at different organizational levels. Such competing interactions lead to SOC, which represents the optimal conditions for the emergence of complexity. Competing interactions and frustrated states permeate biology at all organizational levels and are tightly linked to the ubiquitous competition for limiting resources. This perspective extends from the comparatively simple phenomena occurring in glasses to large-scale events of biological evolution, such as major evolutionary transitions. Frustration caused by competing interactions in multidimensional systems could be the general driving force behind the emergence of complexity, within and beyond the domain of biology.
“Competition for limiting resources” sounds a bit Malthusian. But does competition really “drive” innovation like a physical “force”? Extinction seems an easier way out. As for SOC, If biological systems are “nothing but” physical systems, we should see trilobites emerge from molten metal as it hardens, or from the Mandelbrot set. Koonin and his friends admit that the kind of self-organizing and fractal patterns which can emerge in non-biological systems don’t qualify:
However, contrary to some general statements, there is more to the evolution of complexity than SOC. Importantly, SOC does not lead to hierarchical complexity: Fractal patterns produced by SOC are not genuinely complex because, by definition, they appear the same at all spatial and/or temporal scales.
Try as he might to make biology a special case of physics, Koonin cannot get hierarchical complexity (the “functional wholes” Doug Axe writes about in Undeniable), by the mere operation of fundamental physical laws. The missing ingredient is information from an intelligent source. Only that is able to use physical laws to organize matter for functional ends. Specialists may wish to investigate other ideas in the paper for their philosophical entertainment value. In the final analysis, though, Koonin and friends confess, “the level of complexity and elaboration characteristic of living things is unmatched by anything outside biology.” So what has this paper contributed to understanding the Cambrian explosion and all the other explosions(Bechly, “which are the rule”) from the origin of life till now? Nothing. Frustrating, indeed.
What Does It Mean to Be an Animal?
One last idea comes from a “technology feature” in the Nature journal Lab Animal.In her essay “What is a lab animal,” Ellen P. Neff complains that researchers tend to have a “bilaterian-biased” perspective of animal life. She recommends that biologists consider three very different phyla to answer her opening question, “What does it mean to be an animal?” Those phyla would be:
placozoans, ctenophores, and sponges. Each of them dates back to the Cambrian.
Neff describes many of the peculiarities of these creatures that make them just as interesting as lab rats. You can’t model animals without covering these very distinct groups, she argues, even though they share many of the same genes of the familiar model animals.
The communities studying these three phyla are small and no sponge, ctenophore, or placozoan may ever dethrone the traditional models like the mouse, but putting the time and effort into working with less traditional animals has its place. “We need to keep that breadth, and it’s sort of jolting,” says Leys. “It helps people understand things that are not always typical in mammalian systems.”
The three phyla each have living representatives, which she says have “continued to evolve solutions to life on Earth.” That diversification of these body plans has continued, nobody disputes. The question Neff avoids is how they came to be in the first place.
If we could interrupt Darwinians every time they say a biological phenomenon “has evolved,” and ask how it evolved, debate about the Cambrian explosion would consist of a series of long pauses. But since journals refuse to give voice to Darwin skeptics due to the arbitrary rule of methodological naturalism, the Darwinians continue to get away with non-answers to the origin of hierarchical complexity. Meanwhile, the trilobites look up silently from their Burgess Shale rock slabs, with sad eyes, asking, “Where did I come from?”
No comments:
Post a Comment