The Selfish Grandma Gene: The Roles of the X-Chromosome and Paternity Uncertainty in the Evolution of Grandmothering Behavior and Longevity
Table 1
The circumstances under which an X-linked gene coding for favoritism of granddaughters would persist in a population (based on Rice et al. [8] mathematical model).
When X-linked mutation helping granddaughters at expense of grandsons is expressed in:
It would increase in frequency provided the expense to grandsons is no more than (values below) times the benefit to granddaughters
All grandparents (dominant expression)
2
All grandparents (additive expression)
1.5
Grandmothers only (dom or add expression)
3
Paternal grandmothers only (dom or add expression)