Fig. 3

A thought experiment: Natural selection of E. coli bacteria in Petri dishes favors the beneficial mutation of a glucose transport gene that results in a more efficient conversion of a thermally isolated system to a state of maximum entropy. Three dishes contain equal amounts of glucose at time 0. The glucose in the dish containing no bacteria will degrade relatively inefficiently through oxidation, achieving a state of maximum entropy over a long period of time (red line). In contrast, the glucose in the dish containing a genetically stable strain of bacteria (blue line) will be degraded much more rapidly, since bacteria are highly organized “dissipative structures” that efficiently metabolize glucose. The third dish at time 0 contains the same bacterial strain as the second dish, but soon after (time denoted by green arrow), a subpopulation experiences a rare beneficial mutation in a cell membrane glucose transport gene, rendering it a more efficient glucose transporter compared with the original strain. This more efficient glucose transporting strain (green line) will rapidly out-compete the original strain for glucose, achieving a state of maximum entropy for that dish at a time significantly earlier than the genetically stable bacterial strain (blue line)