Modern-day human evolution can be less obvious. My favorite example are those born with six fingers on each hand (<a href="https://en.wikipedia.org/wiki/Polydactyly" rel="nofollow">https://en.wikipedia.org/wiki/Polydactyly</a>). This uncommon mutation grants a subtle calculation advantage.<p>Think about it. If this mutation had become the norm, we would have base-12 numbers, which over thousands of years could have accelerated mathematical evolution.<p>Nontrivial divisors of 10: 2, 5<p>Nontrivial divisors of 12: 2, 3, 4, 6<p>These people also have an unfair advantage in guitar playing.