Evolution and human behavior • Vol/Iss. 29(1) • Elsevier • • Published In • Pages: 1-18 •
Maternal grandfathers will have a greater effect on child survival than paternal grandfathers (10).
In 10 of 12 populations (83%) for which there was sufficient data, maternal grandfathers had no effect and a positive effect in the remaining 2 populations. In 6 of 12 populations (50%) for which there was sufficient data, paternal grandfathers had no effect, a negative effect in 3, and a positive effect in 3 populations. (Hypothesis tested by observing the proportion of previous studies with the hypothesized effect. No formal statistical test)