In a forest every tree has to compete for light, so genes for growing tall trunks will do well and tend to spread in the gene pool, as all the trees carrying genes for shorter trunks die out in the gloom below. In the end, the forest will consist of trees that all have the tallest trunks they can manage to create.
Who benefits? Not the trees.
They have all invested enormous amounts of energy into growing the trunks and are still competing with each other. There is no way that they could come to a gentleman’s agreement not to bother with trunks, for if some of them did, a cheat could always succeed by breaking the pact. So [tall] forests are a common creation all over the planet.
Susan Blackmore, The Meme Machine, page 42
It’s sort of fun – and a little depressing – to think about the ways that we humans fall victim to this unnecessary competition. Work a few extra hours tonight from home? Check email again just before bed? First thing in the morning? Buy a bigger house because the bank will loan you the money?