A City Guide To Cobourg for 15 In fact, it is the complex structure of the human brain, not only its size, that enables sophisticated speech, reason, and cultural development. Neanderthals had larger heads and larger brains 40,000 years ago than we do today. Yet they were virtually without culture. Nonetheless, the general point remains: while the growth of large, complex brains fostered the development of culture, some rudimentary culture was needed to foster the proliferation of humans with large, complex brains. Human biological development and cultural development have gone hand in hand from time immemorial. As a distinguished biologist observes, attempting completely to separate biology from culture and nature from nurture, as competing causes of human development, is like attempting to determine whether the area of a rectangle is caused more by its length or its width.16 This view was first voiced over two millennia ago. A City Guide To Cobourg 2016.