We now see that natural selection *is* working to conserve this unpartnered region of the Y, ... If mutations do occur in any of these genes, they don't seem to pass on in the lineage. This is a clear example of how evolution is not just about moving ahead, it's also about not falling behind.  -   David Page     Quotes
We now see that natural selection *is* working to conserve this unpartnered region of the Y, ... If mutations do occur in any of these genes, they don't seem to pass on in the lineage. This is a clear example of how evolution is not just about moving ahead, it's also about not falling behind. David Page