Spatial adaptations for plant foraging: women excel and calories count

Abstract

We present evidence for an evolved sexually dimorphic adaptation that activates spatial memory and navigation skills in response to fruits, vegetables and other traditionally gatherable sessile food resources. In spite of extensive evidence for a male advantage on a wide variety of navigational tasks, we demonstrate that a simple but ecologically important shift in content can reverse this sex difference. This effect is predicted by and consistent with the theory that a sexual division in ancestral foraging labour selected for gathering-specific spatial mechanisms, some of which are sexually differentiated. The hypothesis that gathering-specific spatial adaptations exist in the human mind is further supported by our finding that spatial memory is preferentially engaged for resources with higher nutritional quality (e.g. caloric density). This result strongly suggests that the underlying mechanisms evolved in part as adaptations for efficient foraging. Together, these results demonstrate that human spatial cognition is content sensitive, domain specific and designed by natural selection to mesh with important regularities of the ancestral world.

A modulatory effect of male voice pitch on long-term memory in women: evidence of adaptation for mate choice?

“…We demonstrate here that women's memory is enhanced for information that co-occurs with male voices that exhibit a preferred lower pitch, as compared to less preferable raised-pitch male voices. These findings also complement work that appears to reveal potentially adaptive features of long-term memory for food location (New, Krasnow, Truxaw, & Gaulin, 2007), spatial navigation more generally (e.g., Silverman et al, 2000), and future planning (Klein et al, 2010).…”

Sex differences in object location memory: The female advantage of immediate detection of changes

“…De Goede and Postma (2008) found a sex difference in an object location memory task with a delay of 50 min, independent of task instructions. Furthermore, New, Krasnow, Truxaw, and Gaulin (2007) investigated whether females demonstrate superior spatial memory for food resource locations on a real-world scale. The results revealed that women are better than men at pointing to spatial locations that contain nutritional resources.…”

Socio-sexuality and episodic memory function in women: further evidence of an adaptive “mating mode”

“…For example, recall is significantly enhanced when information is encoded in relation to its value for survival in an ancestral grasslands context (e.g., Burns, Burns & Hwang, 2011;Nairne, Thompson, & Pandeirada, 2007). Other memory biases of potential importance from this functionalist perspective have been discovered, including calorie biases in spatial memory for food (New, Krasnow, Truxaw, & Gaulin, 2007) and trade-offs that regulate the social exchange of knowledge about the past (Allan, Midjord, Martin, & Gabbert, 2012;Jaeger, Lauris, Selmeczy, & Dobbins, 2012). In contrast, memory biases triggered by members of the opposite sex that might affect an individual's reproductive fitness have proven to be surprisingly elusive (see, e.g., Anderson et al, 2010).…”