evidence: Cambridge (MA): MIT Press; 2010. [...] Chapter 16The Law of Evolution: Darwin, Wallace, and the Survival of the Fittest [...] Now that was a new concept! Also known as "natural selection," it is a simple statement of the fact that in dangerous circumstances, only those individuals most adapted to their environment survive—and the world, with its limited food supply, fearsome predators, and devastating diseases is always a dangerous place. An individual born with a physical or cognitive difference that renders it stronger or smarter or faster or sharper-eyed—in short, better adapted than its peers to the conditions it is confronting—will be more likely to live and mate and pass on its advantage to the next generation (through, as we now know, its genes). It’s such a simple concept that it’s surprising it took so long to conceive of. When Darwin’s buddies back in England heard it for the first time, they must have slapped themselves on the forehead, chagrined that they had missed so obvious an idea.