Table 2.

Best predictor variables of maximum longevity based on AIC. (Variables occurring in 100% of the set of ‘best’ models are the strongest predictors. Models within 2 AIC units of the ‘best’ model are considered equally good (Burnham & Anderson 2003). Number of ‘best’ models for: mammals, 6; primates, 10; artiodactyls, 22; rodents, 7. See electronic supplementary material for more detailed results of the AIC analyses.)

	per cent of occurrence in the set of best models
predictors	all mammals	primates	artiodactyls	rodents
body mass	100	100	100	100
group size	33	80	91	14
arboreality	100	100	—	100
age at sexual maturity	100	70	32	0
human population density	17	10	45	14
mean temperature	100	70	27	14
mean rainfall	100	60	9	100
absolute latitude	0	90	9	100
longevity sample size	100	100	45	14
group-size sample size	33	10	9	14