Michelle McGrath's blog for Systems Thinking, Certificate Student at Bainbridge Graduate Institute
Friday, February 11, 2011
Capra and Nature
In Chapter 8, Capra digs deeper into dissipative structures. He helped define the nature of these structures in Chapter 7 by stating that they are structurally stable while continuous flowing. It is the flow of energy or matter in and out of the structure that makes it dissipative. He again refers to the cell as an example in Chapter 7. In Chapter 8, he uses a food cycle of an ecosystem as an example of a dissipative structure. Clearly, nature is an open system, but with structure. As Capra puts it, " The understanding of living structures as open systems provided an important new perspective, but it did not solve the puzzle of the coexistence of structure and change, order and disorder." The idea of dissipative structures helped ease the seeming conflict of interest of order and disorder.
Capra discusses bifurcation points as "thresholds of stability at which the dissipative structure may either break down or break through to of several new states of order." There are many things that affect the direction of this bifurcation point. A few of Capra's points stuck with me, particular with my mind constantly relating the ideas to an ecosystem: (1) History matters, (2) Noise matters, (3) Nature is unpredictable. I think with regards to ecosystem modeling, these points are particularly important.
And then, Chapter 9 appears and I lose my understanding of autopoiesis again. I was thinking of autopoiesis as the pattern of life, but it appears to mean more or less: life-like in pattern? Scientists have been able to "simulate" life by creating autopoietic, self-organizing networks. These modeled systems eventually returned to a state they had been to previously, and a cycle of states begins again. Capra calls these "cycles of states" attractors, and then he uses the word attractors again and again. As I often do when I don't understand Capra, I looked up "attractors" on Wikipedia. They define it as "a set towards which a dynamical system evolves over time." Capra refers to living sytems in nature, and states that many of them--including ecosystems--are really just autopoietic systems that exhibit many alternative attractors. Although these systems have a chaotic element to them, they also display order. Figure 9-4 elegantly displays the relationship between complexity and the number of attractors. Capra references the fact that the components of dynamic living systems have different levels of independent existence.
Of course as we are discussing autopoiesis, dissipative structures, autopoietic networks, it only makes sense to discuss the Gaia hypothesis. Capra goes in depth to discuss the various aspects of the Gaia system as it relates to autopoiesis: self-bounded, self-generating, and self-perpetuating. "A key characteristic of Gaia is the complex interweaving of living and nonliving systems within a single web. This results in feedback loops of vastly different scales." These feedback loops of various scales, are what fascinated me as an ecologist and evolutionary biologist.
*Phew* That was a lot of Capra to digest.
Monday, February 7, 2011
More Marvelous Meadows
Wheatley on Self-Organizing Systems
Sunday, February 6, 2011
Spirals & Shells
My husband and I have been spending a lot of time discussing the course material, and we've rented some documentaries via netflix related to the course topics. Last night we watched a documentary on fractals. It was a very brief introduction to the topic, and it made me want to take more advance math to deepen my understanding of them. They are beautiful examples of living systems.
I am curious how fractals relate to patterns of behavior? It seems to me to be stuck in a repeating self-similar pattern of a behavior would be a bad thing most often. In fact, it seems any repeating pattern of behavior would have negative connotations. Can someone give me an example of a positive repetitive pattern of behavior? I think only in a pattern that enables growth would positive outcomes be possible.
One of the topics discussed in the documentary was the occurrence of fractals in nature and art. Specifically, they highlighted the Japanese artist Hokusai. You are likely familiar with his famous painting of a giant wave and Mt. Fuji.
They identified the repeating curls of the wave within waves as a fractal. I also see the beginnings of a spiral. Spirals are fascinating patterns found throughout art, mythology, and nature. Much like fractals, they can be reduced to a mathematical formula (for more information on the math behind spirals, read about the golden ratio and the Fibonacci spiral).
Wednesday, February 2, 2011
My love/hate relationship with Fritjof Capra
Capra- Chapter 5.
I've read parts of this chapter 2-3 times. Something about the way Capra communicates just doesn't get fit with my learning style. I can't understand what he's trying to get at. I'm still upset about his comments about molecular biologists (which are heavy in the first part of Chapter 5), but for the sake of productivity I will not whine about them here---except to say, I feel Capra owes molecular biologists an apology. In Chapter 5, Capra gets defensive of systems thinking when a critique accuses the field of being vague. Capra claims that the critique is unjustified as systems thinking has advanced major understandings in the scientific understanding of life. I would say the same about molecular biology. In fact, I think it is much truer that systems thinking and molecular biology need each other, than it is that either is wrong. Two heads are better than one, they say.
Capra himself says in Chapter 5 that the synthesis of the study of structure and pattern is t”he key to a comprehensive theory of living systems.” Of course, he elevates the study of pattern over the study of structure, and doesn't pass up the opportunity to take another punch at “reductionist scientists.” I've met a lot of scientists. I haven't met a single one who wouldn't admit that the system as a whole affects all the parts within that system, and that life is fast and complicated. Perhaps Capra's criticism is a bit outdated? 99% of the scientists I know has gone out of their way to set up a collaboration, because they know that life is more complex than their particularly specialty and narrow focus.
Capra's irksome attacks on science aside, I have always been fascinated with the patterns of life, and I enjoyed the discussion about networks. The idea of self-organization was really interesting, especially the switch-board example (I like it when Capra uses examples, instead of resorting to language that is difficult for the uninitiated to understand). There are networks with rules at there nodes everywhere we look, although most often we don't know it. These self-organizing networks are what rule the world.
Capra discusses that “living organisms are able to maintain their processes under conditions of non-equilibrium.” This fact has enormous implications for ecology and evolution. I think it's important to note, however, that all living organisms and living systems have thresholds beyond which they have reached the point of no-return---death, then becomes the solution. If we don't know the threshold, then we shouldn't test how hard we can push the system from it's equilibrium. I've argued this EXACT point in a salmon population modeling course. The idea of life processes existing under non-equilibrium conditions is interesting from a sustainability perspective when the threshold is mentioned. It seems a little careless it was not. Perhaps I am missing Capra's point or perhaps it will be mentioned later.
I had a hard time understanding the parts about chemical self-organization and lasers (physics is NOT my strong point), but I definitely find the emergence of these patterns fascinating (I do better with larger structures, like crystals). I also find it fascinating that a period of instability always precedes the self-organization. Also, it makes sense to me that physics is non-linear. I can accept this idea easily.
Chapter 5 is an insanely long chapter, so for the sake of brevity, I will just post my superficial reactions to rest of the chapter.
*Hypercycles: Enzymatic feedback loops—much better studied zoomed out. I had to memorize these loops in college in my metabolic biochemistry course and it was really really difficulty. They are pretty awesome, however. I love the idea that “ the roots of life reach down into the realm of nonliving matter. Capra doesn't talk about an “RNA” world, but I think Eigen's initial ideas probably informed the “RNA world” hypothesis.
*Autopoiesis: This is another part of the book where I get lost--”living is a process of cognition.” I'm not really sure what the BIG DISCOVERY is here. I think the discovery meant that the system has internal and external factors influencing the feedback loop, and that your own perception helps shape your reality...but again, I was a confused by Capra's writing in this part. I am not sure I get it.
*Gaia hypothesis: Reading this books reminds me that I have taken for granted the things I believe to be true. OF COURSE the earth is self-regulating. I am grateful for the “revolutionaries” who drove this point home in the 60s and 70s. THE WORLD IS NOT FLAT.
Tuesday, February 1, 2011
Dichotomous Key

