HONORS 232 Lecture Notes - Lecture 8: Encephalization, Striatum, Foxp2
Document Summary
Lecture eight: encephalization quotient: observed brain size over the expected brain size, proposed measure of intelligence, there has been an increase in primates i. ii. iii. Thus the maturation was probably slower than modern humans, less postnatal growth: how can energetic constraints be overcome, expensive tissue hypothesis: the brain is 300% of expected size, but the gut is. Additionally, the brain takes up 18% of metabolic energy but. Supported by study that basal metabolic rate and gestation period are positively correlated with brain size in primates. Frugivores have larger brains than folivores which they need for complex foraging and larger home and day ranges i: social intelligence hypothesis: complex social structures select for bigger brains i. Executive brain ratio ((neocortex+striatum)/brain stem) is greater in primates with higher frequencies of social learning: behavioral flexibility hypothesis: must cope with both food and social related issues with leads to a bigger brain i. ii. iii. Learning often involves both social and ecological problems.
