Overview: Do males and females think differently? Some interesting differences: I sex differences in spatial ability I sex differences in navigation I sex differences in range size I Relationships between range size and spatial ability Explanations I Evolutionary hypotheses: benefits to males I Evolutionary hypotheses: costs to females I Evidence: Voles and People Some sex differences in cognition and behavior (from Melissa Hines, 2003) Caveat: even with a large sex difference. . . There is a lots of overlap between males and females Caveat: Nature and nurture interact Task behavior in children amplifies sex differences Caveat: Nature and nurture interact Task behavior in children amplifies sex differences This talk: Spatial abillity and navigation Males usually better at geometric spatial tasks 1. Mental rotation Males usually better at geometric spatial tasks 1. Mental rotation 2. Spatial perception Males usually better at geometric spatial tasks 1. Mental rotation 2. Spatial perception 3. Targeting (hitting and intercepting moving objects) This sex difference in spatial ability I is found cross-culturally I is found in some other species I is related to sex differences in range size and navigation Women often better at remembering relative position of objects Stimulus Figure Test Figure (some objects moved) Twe Study What is spatial ability good for? Navigating Men and women navigate differently: Men attend more to geocentric cues: I indicate absolute distance and direction I example: “go north 4 miles” I enables short-cuts I probably related to skill at geometric spatial tasks What is spatial ability good for? Navigating Men and women navigate differently: Men attend more to geocentric cues: I indicate absolute distance and direction I example: “go north 4 miles” I enables short-cuts I probably related to skill at geometric spatial tasks Women may attend more to egocentric cues: I note local landmark’s position in reference to self (“ego”) I example: “turn left at the church” I can use to retrace route, no shortcuts Why a sex difference in navigation? Men more likely to travel to distant places: Aka foragers Twe forager-farmers Men who travel farther have better spatial ability True for Canadian men also (but not Canadian women) Overview: Do males and females think differently? Some interesting differences: I sex differences in spatial ability I sex differences in navigation I sex differences in range size I Relationships between range size and spatial ability Explanations I Evolutionary hypotheses: benefits to males I Evolutionary hypotheses: costs to females I Evidence: Voles and People Some evolutionary hypotheses I benefits to males: hunting? I I foraging ranges of men larger than of women (Hadza) hunting mobile prey takes you off an established path Some evolutionary hypotheses I benefits to males: hunting? I I I foraging ranges of men larger than of women (Hadza) hunting mobile prey takes you off an established path benefits to males: mating competition? I I same sex difference found in some polygynous rodents humans? Some evolutionary hypotheses I benefits to males: hunting? I I I benefits to males: mating competition? I I I foraging ranges of men larger than of women (Hadza) hunting mobile prey takes you off an established path same sex difference found in some polygynous rodents humans? costs and risks to reproductive-aged females: parenting? I I energetic costs of carrying an infant risk of travel: children suffer more from loss of mother than father The mating hypothesis: Voles Monogamous vole species Polygynous vole species The mating hypothesis: Voles Pine voles are monogamous, Meadow voles are polygynous Males Females Meadow Voles Pine voles Sex Differences in Range size Sex differences in Spatial ability But human mating is different. . . Or is it? Tsimane range size: Twe men and mating success: also probably related The parenting hypothesis I I Females are more “harm avoidant” Harm avoidant people don’t travel as far Overview: Do males and females think differently? Some interesting differences: I sex differences in spatial ability I sex differences in navigation I sex differences in range size I Relationships between range size and spatial ability Explanations I Evolutionary hypotheses: benefits to males I Evolutionary hypotheses: costs to females I Evidence: Voles and People