Female putty-nosed monkeys deliberately use alarm calls to recruit males to defend the group. This is the conclusion reached by Claudia Stephan, an evolutionary biologist at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), together with colleagues from the Wildlife Conservation Society after conducting observations in the Republic of the Congo. The females kept up their chirping calls until the male took action to defend the group against the predator. This is the first time that intentional vocalization such as this has been observed in the animal kingdom. The researcher has now published her findings in the scientific journal “Animal Behavior and Cognition“.