Territorial aggressiveness is another name for space hostility. It also contains the signs that animals use to deter intruders from entering their territory. The majority of male animals warn other male intruders to leave a territory, however these males are nonetheless tolerant of female intruders. For instance, pheromone is used by other ants to signal alarm when a stranger approaches an ant colony. Baboons from Africa compete with seals for rocky areas and sleeping trees, respectively.