Back in 1966, evolutionary biologist George Christopher Williams wrote: “I regard it as unfortunate that the theory of natural selection was first developed as an explanation for evolutionary change. It is much more important as an explanation for the maintenance of adaptation. ”
खरे पाहता हा सिद्धान्त, प्राणी किंवा वनस्पती कशाप्रकारे आपल्या वातावरणाशी समरस होण्याकरता बदलत जातात याचे स्पष्टीकरण देण्याकरता जास्त उपयुक्‍त आहे. ”