Article reads: Biological evolution through natural selection is a powerful and successful mechanism, which is now successfully challenging Roundup. It works as follows. Variety exists in every biological population, including weeds. Variety also continually arises naturally though mutations – random genetic changes. While the great majority of individual weeds succumb to Roundup, some varieties are more resistant. Constantly challenging the weeds with Roundup means that the Roundup-resistant varieties come to prominence and soon dominate the variety spectrum present in the weeds. Eventually Roundup becomes ineffective.