The bears that lived in the polar region survived best if they had white coats of fur and thick layers of fat in their bodies. After some generations this type of bear was all that was left in this region, so we had the polar bear created as a direct result of natural selection. This bear is very well suited to the cold climate where it lives. It has, however, lost the genetic information to produce baby bears that have dark fur or lack a layer of thick fat. This example demonstrates that natural selection is a loss of genetic information and therefore can t in any way help evolution.
Natural selection is a process that goes in exactly the opposite direction required for evolution.