The brain of a chimpanzee has a volume of 370mL on average. In contrast, humans have a brain size of 1350mL on average. Brain size alone, however, is not an absolute indicator of intelligence. There have been Nobel Prize winners with brains ranging from below 900mL all the way up to over 2000mL. The structure and organization of the various parts of the brain is a better way of determining intelligence. Human brains have a high surface area because they are much more wrinkled than chimpanzee brains, with greater numbers of connections between many of its parts. These, as well as a relatively larger frontal lobe, allow us much more of the luxury of abstract and logical thought.