Phylogenetic comparative methods and a sample of over 500 mammalian species show that mammals in which males carry the offspring have shorter lactation periods, which leads to more frequent breeding events. Provisioning the female is associated with larger litters and shorter lactation.

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Phylogenetic comparative methods and a sample of over 500 mammalian species show that mammals in which males carry the offspring have shorter lactation periods, which leads to more frequent breeding events. Provisioning the female is associated with larger litters and shorter lactation.