Fat-Tailed Distributions

Biological Parallel

Most trees in a forest are small; a few are giants. Most earthquakes barely register; rare megaquakes reshape continents. Normal distributions predict averages; fat-tailed distributions predict that extreme events happen more often than statistics suggest. In biology, these appear everywhere: extinction event sizes, epidemic spread rates, species abundance in ecosystems (power law distributions). Evolution doesn't prepare organisms for the average day—it prepares them for the tail events that determine survival.