Do women with asymmetrical ears lack empathy? Trying to find out what Robert Trivers was up to these days, I discovered this account of his research in Jamaica.
The first article based on the research has appeared in the journal Evolution and Human Behavior. It shows that Jamaican schoolgirls are more likely to cradle a doll on the life side of their bodies if their ears are more symmetrical, while symmetry elsewhere (for example, of their fingers or elbows) is unrelated to the tendency to cradle on the left-hand side. Jamaican boys show no over-all tendency to cradle on the left-hand side and no association with symmetry of ears or any other body part. In this, Jamiacan children resemble British adults: women tend to cradle their babies on the left side if their ears are more symmetrical (but not other body parts) while men show no cradlng bias. We interpret these results as making sense because information going into the left ear (and left visual field) go immediately to the right half of the brain, which is specialized for interpreting emotional information (such as is conveyed in a baby’s voice and actions). This specialization is particularly well-developed in women and we believe that asymmetry of the ears partly reflects a breakdown of the usual pattern.