There appears, in particular, to be a problem with a phenomenon known as genetic imprinting.

ECONOMIST: Cloning around

MacDorman's current focus is on the uncanny valley with respect to empathy: that is, is the uncanny valley phenomenon related to a person's difficulty in identifying with particular computer-animated or robotic characters in films?

CNN: Why zombies, robots, clowns freak us out

All this suggests that the prolonged old age of people women in particular is indeed an evolved phenomenon, rather than being a consequence of better living conditions.

ECONOMIST: Why women live so long

The report highlights in particular the increasing phenomenon of migration from rural to urban areas, often as a result of drought or flooding in the countryside.

BBC: Indian children 'malnourished'

As a result, males in particular tend to develop characteristics designed to persuade females that they are the most desirable mates around a phenomenon known as sexual selection.

ECONOMIST: What is music for?