Teaching material for evolution by natural selection

In honor of Darwin's recent 200th birthday, Nature came up with a list of 15 Evolutionary Gems. My major complaint, and a pretty major one at that, is that none of the examples are related to human evolution - something that students could probably relate to a bit more easily, and might increase the chance that they actually pay attention.
Basically, what I'm getting at: Why is lactase persistence not there? or the several other well-documented and clear cut examples from human evolution?