I appreciate the evolutionary metaphor, but its also important to remember that candidates can (and do) change strategies and adapt to circumstances. Indeed, I would expect an intelligent candidate to try various different strategies throughout their campaign (and be better at it than their competition). Clinton and Trump both did. Clinton also had arguably much more help from very powerful allies, and had much more funding.

Also, developing limbs is not a choice; campaign strategy is.

How are you judging whether Trump is intelligent or not? Just because his words/actions seem irrational to you doesn't mean they are irrational. Scott Adams was pretty good at predicting Trump's behavior, so Trump's decision made sense to at least someone.