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Figure 2 | Theoretical Biology and Medical Modelling

Figure 2

From: Order without design

Figure 2

The Benard instability. Establishing an increasing vertical temperature gradient (ΔT) across a thin layer of liquid leads to heat transfer through the layer by conduction (organizational state #1). Upon reaching a certain critical value of temperature gradient (ΔTC), an organizational state transition takes place within the liquid layer and conduction is replaced by convection (organizational state #2), leading to a stepwise increase in the rate of heat transfer through the layer. The organizational state #2 (i.e., convection) is a more ordered state (higher negative entropy) than the organizational state #1 (i.e., conduction), and, thus, it requires a higher rate of energy/matter flow through the system for its maintenance. The organizational state #2 (convection) will relax into the organizational state #1 (conduction) upon decreasing temperature gradient (not shown). The Benard instability is an example of a nonequilibrium nonliving system displaying a number of the universal (self-) organizational law-like patterns shared by all nonequilibrium system, including living organizations/systems, broadly defined (see discussion in the text). Reproduced from [20].

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