Relationships between primates and snakes are of widespread
interest from anthropological, psychological, and evolutionary
perspectives, but surprisingly, little is known about the dangers
that serpents have posed to people with prehistoric lifestyles and
nonhuman primates. Here, we report ethnographic observations
of 120 Philippine Agta Negritos when they were still preliterate
hunter–gatherers, among whom 26% of adult males had survived
predation attempts by reticulated pythons. Six fatal attacks occurred between 1934 and 1973. Agta ate pythons as well as deer,
wild pigs, and monkeys, which are also eaten by pythons, and
therefore, the two species were reciprocally prey, predators, and
potential competitors. Natural history data document snake predation on tree shrews and 26 species of nonhuman primates as
well as many species of primates approaching, mobbing, killing,
and sometimes eating snakes. These findings, interpreted within
the context of snake and primate phylogenies, corroborate the
hypothesis that complex ecological interactions have long characterized our shared evolutionary history.