Skip to main content

Table 1 Model notation

From: Caring for parents: an evolutionary rationale

Life-history parameters
α Number of offspring
ω1 Survival of the first age class (offspring)
ω2 Survival of the first reproductive class (parents)
ω3 Survival of the non-reproductive class (grandparents)
Benefit parameters
a21 Efficacy of a grandparent’s help on the survival of the offspring
b Effectiveness of backward help, the maximum efficacy of the parents’ help on the grandparent’s survival