Many species have finely tuned territorial instincts that have evolved to do exactly that: restrain growth to sustainable numbers. Individuals who fail to domin

Many species have finely tuned territorial instincts that have evolved to do exactly that: restrain growth to sustainable numbers. Individuals who fail to dominate sufficient territory won't breed at all. Just yesterday I observed two swans in busy border negotiations, a quiet "dance" that has more similarities with a proof of work algorithm than with an actual fight. On a macro level, sure, it was unconstrained growth and the resulting hardship that caused these patterns to evolve, but that evolution has happened many times.