In this sense, economists are merely reclaiming one of their own ideas: Darwin borrowed the theory of natural selection from the economist Thomas Malthus.
To some extent, there's nothing new in this. Economists have long argued that their apparently silly idea that companies and people rationally maximise their self-interest makes sense only as the outcome of natural selection. The late Milton Friedman said that irrational, destabilising speculation could not persist because speculators who bought overpriced assets - thus driving their prices even higher - would lose money and so leave the market. Darwinian selection would kill them off.