In 2011, Charles Goodnight and I had an idea about how post-reproductive life span might evolve, an idea that sounds pretty unlikely in the abstract, but when we did the numbers, it actually panned out. An older, “retired” segment of the population, we argued, serves to keep the population stable over cycles of feast and famine. When times are good, they eat the excess food and help prevent population overshoot. When food is scarce, they are the first to die.



posted 2725 days ago