No one did. That&#x27;s not how evolution works. There is no plan, and no one decided how it would work in the future. Your second question makes me think that you&#x27;re thinking of evolution as &quot;progress&quot;, that everything is evolving <i>towards</i> something. It is not. That is, you&#x27;re asking, given an adaption, what is the likelihood of those genes existing? But that&#x27;s backwards; the genes <i>caused</i> the outcome.