Brittle Power- PARTS 1-3 (+Notes) - Natural Capitalism Solutions

Chapter Thirteen: Designing for Resilience 187Hierarchical structures Ecosystems achieve active resilience partly by theirlayered structure of successively more complex and specialized organisms.Low-level layers contain a relatively large number of relatively small componentswith different functions. The integration of these components producesor supports the next higher layer, as in a food chain. Successively higher layerscover a larger area and work more slowly. Within this complex structure,at each level, “the details of operations [among] the components can shift,change, and adapt without threatening the whole.” 39For example, ecosystems use many overlapping, interchangeable populationsto perform the same function, such as primary food production. This ispartly a precaution against uncertainty: since sunlight is not uniform, forexample, a diverse forest may contain both sun-loving and shade-tolerantplants. “Any particular function represents a role that at different times can beperformed by different actors (species) that happen to be those available andbest suited for the moment.” 40 Thus the primary production by algae in a lakestays essentially constant from one season or year to the next, but the kinds ofalgae doing most of the production can change markedly. 41 The higher organismsin the lake are undisturbed; they simply eat algae and are not finickyabout which kinds currently dominate.The mathematics of such hierarchical structures “allows rapid evolutionand the absorption and utilization of unexpected events.” 42 It is common tofind ten or twenty species able to perform the same basic role (such as primaryproduction in a lake), yet each with a unique variation which makes it betterable to exploit a particular opportunity in the changing conditions of themoment. The constant flux of circumstances ensures that this diversity will beretained, since whatever happens “will be at least one species’ boat come in.” 43If a long spell of constant, predictable conditions should cause this essentialdiversity to be lost, the ecosystem might no longer be able to tolerate evenmodest environmental changes.The importance of a layered structure, with each level of a system unaffectedby the substitutions among the elements of another level, is illustratedby H.A. Simon’s anecdote about the different working methods of two imaginarySwiss watch-makers.One watch-maker assembles his watch (by combining)…a sequence of [self-contained]subassemblies—a hierarchical approach. The other [merely]…builds from thebasic elements. Each watch-maker is frequently interrupted by phone calls and eachinterruption causes an[y incomplete] assembly to fall apart… If the interruptions arefrequent enough, the second watch-maker, having always to start from scratch, mightnever succeed in making a watch. The first…,however, having a number of organized