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Young female spotted hyaenas prefer to breed with short-tenured rather than long-tenured males1,3. This preference cannot be explained by a rule based on dispersal status but must involve tenure-based rules such as those suggested by us1.

In spotted hyaenas, many natal males do not display sexual interest in females before they disperse1,2,3,4. Because females are unlikely to consider such males as potential mates, they should be excluded from tests of female mate preferences1,3,5,6, as is common practice among primatologists5,6. Any appropriate test of female mate preference then considers the number of reproductively active natal males and immigrant males at the conception of each litter and averages the results over all litters per female to yield one data point per female1,7. The comparisons by Van Horn et al.2 of the percentage success of natal males and immigrant males in the pools of all natal males and all immigrant males present during their study do not recognize these aspects.

First, their tests of preference include natal males without considering their reproductive activity. Their2 quote of 68%8 of natal males in their Crocuta study group (in contrast to 11% in our study population1) showing reproductive behaviour to females is puzzling given that testosterone concentrations of natal males resemble testosterone concentrations of juvenile non-reproductive males9. In the paternity analysis of Van Horn et al.2 (citing ref. 10), natal males are assumed not to be candidates and therefore presumptively excluded if they are a relative (at r ≥ 0.125) of the female, thereby reducing the chance of natal males being identified as sires. Thus, the tests of preference by Van Horn et al.2 and a previous paternity study on the same clan10 compare the reproductive success of unrelated natal males with a pool comprising reproductively active and inactive, sexually immature, related and unrelated natal males, thereby reducing the percentage of successful natal males and favouring immigrant males6,7.

Second, Van Horn et al.2 did not take into account the fact that male reproductive success strongly increases with tenure3,10. With their method, reproductive success becomes skewed towards long-tenured immigrant males10 owing to significant differences in mean tenure between immigrant males and natal males3,10. This demonstrates the importance of tenure, not dispersal status.

Third, for their 22 litters apparently not conforming to the tenure-based rule, Van Horn et al.2 do not provide any evidence or test that compares the availability of immigrant males and reproductively active natal males on the dates of conception, nor the availability of males born/immigrated before and after the female’s birth.

Van Horn et al.2 state that our result that females avoid males present when the females are born1 may reflect a lack of such male candidates. This is incorrect because our test considered the proportion of candidate males that initiated their reproductive career before and after the females were born1. And if we consider only those litters where females can choose between both males that initiated their tenure before and after the female’s birth, they still strongly avoid males present when they were born (Wilcoxon signed-rank test, n = 54 females, P = 0.0001).

Do females prefer immigrant males in our eight study groups? No: the reproductive success of natal males during their reproductive tenure1 did not differ from the mean reproductive success of their immediate immigrant male predecessor and successor during the same duration of tenure (Wilcoxon signed-rank test, n = 12, exact P = 0.148, power = 0.35).