Sure. sometimes a whole segment of DNA gets duplicated where gene is involved and the net effect is that an individual has an extra copy of the gene. &amp;gt;&amp;gt; But why is that a good thing? &amp;gt;&amp;gt; Well, you can think about it as a new source of material for evolution to act on. &amp;gt;&amp;gt; So the extra copy, one can just have a mutation and have a whole new function? &amp;gt;&amp;gt; Sure. 