Design In Nature

--“In addition, the force output of the muscles of swimmers, runners, and fliers can be calculated from their weight: It is, for all of them, roughly equal to twice their body weight.” (82)

--“…good design involves the nearly uniform distribution of imperfection throughout the entire flow system.” (65)

--“The bifurcated structure of lungs, the round tube shapes of pipes, the cracking pattern of drying mudflats are all designs that distribute their resistances so that globally the flow system becomes less and less imperfect.” (83)

--“…contrast, which is the essence of design.” (62)

--“Science is effective because it is concise. It converts physical phenomena into statements, formulas, and mathematical equations that have great explanatory power. In the process, it also tends to sever objects from their natural state. The mighty Danube ferrying water from central Europe or an elegant antelope jumping across the savanna loses its essential character when translated into data.” (55)

--“People, then, are only half right when they say things seek the path of least resistance. Instead of finding these already cleared paths, flow systems construct their own flow architectures and body rhythms that enable them to move more easily.” (52)

--“The movement toward equilibrium—and the pull of gravity—puts things in motion.” (53)

--“A prerequisite, then, is for the flow system to be free to morph. The emerging flow architecture is the means by which the flow system achieves its objective under constraints. Freedom is good for design.” (44)

--“Imperfections are unavoidable. In fact, they are necessary. Without imperfections (resistances), flow systems would accelerate continuously, eventually spinning out of control. Thus, imperfection (friction, heat leaks, etc.) acts as a brake on the engines (the designs) that drive flow.” (42)

--“…while a system cannot create energy, it will conserve and can transform it.” (40)

--“Consider the snowflake. The prevailing view in science is that the intricate crystals formed by the snowflake have no function. This is wrong. In fact, the snowflake is a flow design for dispersing the heat—called the latent heat of solidification—generated on its surfaces during freezing. As water vapor condenses and freezes it throws off its excess heat. When the ice crystal first forms, its spherical bead is the shape that grows faster than other shapes, the shape that facilitates rapid solidification. When the bead is large enough, needles emerge and enhance solidification (that is, produce ice) faster than the sphere. To facilitate solidification even more, larger snowflakes morph into shapes with more needles that disperse heat.” (10)

--“The engineered world we have built so that we can move more easily does not copy any part of the natural design; it is a manifestation of it.” (4)

--Definition of the ‘constructal law’: “For a finite-size flow system to persist in time (to live), its configuration must evolve in such a way that provides easier access to the currents that flow through it.” (3)

--“Everything that moves, whether animate or inanimate, is a flow system…. The designs we see in nature are not the result of chance. They arise naturally, spontaneously, because they enhance access to flow in time.” (3)

--Two basic features to flow systems. “Flow systems have two basic features (properties). There is the current that is flowing (for example, fluid, heat, mass, or information) and the design through which it flows. A lightning bolt, for example, is a flow system for discharging electricity from a cloud. In a flash it creates a brilliant branched structure because this is a very efficient way to move a current (electricity) from a volume (the cloud) to a point (the church steeple or another cloud).” (3-4)

--“Life is movement and the constant morphing of the design of this movement. To be alive is to keep on flowing and morphing.” (6)