To ascribe purpose to evolution is to engage jn anthropomorphism. There is no purpose in evolution; in order for it to work independent of a guiding hand, it must be seen as totally random and subject to the laws of nature, physics, chemistry and mathematics. The law of large numbers is its bedrock, and natural variability and natural selection it's foundation. Without both, evolution would crumble, as it would be devoid of both method and means.
The purpose of evolution to mankind is the general development to a new and different kind of species. This refers to the grows in terms of mind, way of living, body structure among others. This development brings about new understanding and appreciation.