"Grow fast and die fast" also carries a predation cost in wildebeest

Large herbivores must forage for many hours every day and ruminants must also regurgitate and masticate that forage for several additional hours.  The rate at which a larger herbivore can allocate resources to growth and reproduction depends, partly on the rate at which it processes forage.  However, foraging also wears down teeth and herbivore lifespan is strongly limited by the condition of teeth.  These processes frame a well-known but simplistic tradeoff between longevity and early allocaiton of resources to growth and reproduction - the "grow fast/die fast" tradeoff.  Predators are known to exploit indivdiuals that vary in conidtion and investment in foraging effort, but predators are rarely considered in this classical tradeoff.

We collected the first incisor from adult wildebeest killed by stalking carnivores (lions and cheetah) and coursing carnivores (spotted hyena and African wild dog) in Liuwa Plain National Park, Zambia.  We measured wear on the first incisor and estimated age of each wildebeest using cementum annuli.  We then compared the age-corrected wear of each predator type's kills.

The amount of tooth wear seen in wildebeest varies depending on sex, but also on the cause of death. In Liuwa Plain Naitonal Park, Zambia, Adult male wildebeest killed by lions and cheetah have worn down their teeth at a faster rate than male wildebeest killed by spotted hyena and African wild dog. Female wildebeest show the exact opposite pattern.

Predation risk interacts with life history tradeoffs between longevity and early resource allocation but their is a orey gender interaction with hunting style in predators.  It is unclear exactly what environmental or behavior processes may shape this interaction and future work should attempt to quantify investment in growth and reproduciton more directly.