On the Stability of Life
Joshua Plotkin
Martin Meyerson Assistant Professor in Interdisciplinary Studies
Ask yourselves: Is life possible? It doesn’t seem so, at least thermodynamically. After all, your skin cells are replaced every 6 weeks. All the atoms in your body are recycled each year, replaced by other atoms that were created billions of years ago, light-years away. And so in what sense are you the same person from year to year? Certainly in no physical sense. But you think you are alive, and stable enough to call yourself an individual. In what sense, then, are you stable? In an evolutionary sense. Your genetic information, though thermodynamically fragile, is dynamically repaired and transmitted with fidelity. Not perfect fidelity, thank goodness. Imperfections do arise from time to time. Without these mutations, evolution could not proceed. And so, the same entropic forces that threaten to destabilize life also allow life to evolve. Think about that, for a minute.