Bulls live differently. Young males leave the natal herd at around twelve years old and spend the rest of their lives alone or in loose bachelor groups. The largest bulls enter a periodic hormonal state called musth, during which testosterone levels rise forty times above normal, temporal glands stream dark fluid down the sides of the face, and the bull becomes aggressive and single minded about mating. A bull in musth can be recognised at a distance by the wet streaks on his cheeks and the slow heavy walk. Their intelligence runs deeper than most travellers expect. Elephants recognise themselves in mirrors, use tools, mourn their dead by returning to the bones of lost relatives years later to touch the skulls with their trunks, and communicate across distances of several kilometres through deep infrasonic rumbles that travel through the ground as well as the air. They have a specific alarm call for humans, a different one for bees, and a third for lions. Tanzania's elephants carry one of the heaviest stories in African conservation. The country lost roughly 60 percent of its elephants to poaching between 2009 and 2014, one of the worst ivory crises ever recorded. Since then, improved anti poaching and international ivory bans have stabilised the population and allowed Tarangire in particular to begin recovering. The herds you see there today are the survivors and their children, and the calves you watch in the Tarangire River in October are proof that the story can still change.