但是复杂的动物以某种程度上获得了自适应灵活性 - 他们将一种依赖性交易给了另一种。不再需要改变身体以适应，因为现在他们的适应是行为，社会上确定。这种行为需要学习。从某种意义上说，在高等动物中，自适应适应性根本不再通过DNA传播到下一代。现在是通过教学携带的。
(But complex animals had obtained their adaptive flexibility at some cost--they had traded one dependency for another. It was no longer necessary to change their bodies to adapt, because now their adaptation was behavior, socially determined. That behavior required learning. In a sense, among higher animals adaptive fitness was no longer transmitted to the next generation by DNA at all. It was now carried by teaching.)