in his toddler years. He is part of a close-knit tribe of Chimpanzees. They occupy a forest territory which is rich in native fruits, nuts, and figs, among other things. The chimps hunt small tree monkey, and they also eat ants. Oscar is tended by his mother, nicknamed Eesha, and from her he begins learning many things about how to survive in the jungle. In the chaos of an attempted raid by a rival gang of chimpanzees, led by 'Scar', Eesha is injured and separated from the group and her son. As told by narrator, Eesha is most probably the victim of a nocturnal leopard.
Unaware of his mother's death, Oscar spends much of his time looking for her. He finds trouble in recalling the things she taught him and begins to lose weight quickly. He attempts to find another mother to take care of him; however, none of the females can afford him, having young of their own to raise. As time goes on, Oscar is rejected by nearly every chimp in the group, until the only one left to ask is the tough-skinned leader, 'Freddie'. However, as Oscar follows the leader and imitates him, it is soon revealed that the unlikely duo may work out. The two gradually warm up to each other more and more, until one day Freddie lets Oscar ride on his back, something normally only mother chimps do. In this way, Freddie "adopts" Oscar.
As the rivals prepare for attack, Freddie is forced to take time away from Oscar to organize the other members of the group, and this leaves the young chimp confused. Scar leads a vicious attack, although because of the unity of Freddie's group, they have a rousing success, and Scar and the enemy chimps retreat into the jungle. A few months later, it is revealed that the bond between Freddie and Oscar has continued to grow, and that life in the group is slowly returning to normal.