I'm not going to tell you what it is. You'll have to read his article. But here are a few hints.
- The mutation is only common in Europeans. Asians and Africans get along just fine without it.
- It's not clear whether the mutation confers selective advantage. There's some evidence that it does but it's difficult to understand why.
- There are several different mutations that produce the same phenotype and it's not clear which one of them is the "most spectacular."
- The article claims that the mutation appeared 10,000 years ago but that's probably not true.
- The mutation has nothing to do with walking upright, opposable thumbs, big brains, or the ability to talk. Apparently those mutations are either much less spectacular or they don't qualify as "recent."
[Photo Credit: How to Milk a Cow]
[Hat Tip: Mike the Mad Biologist]