Elders pass the village's accumulated wisdom and knowledge to the young.
Villages compete for scarce land, game, and potable water. Without elders, each generation in a village would need to "reinvent the wheel" in the "school of hard knocks". With elders, each generation of a village can "stand on the shoulders of giants", enjoying the benefit of the village's accumulated wisdom and knowledge. A village that honored its elders had a competitive advantage in the game of life presented by the jungle.