: Humankind is not "naturally," 5 feet 10 3/4 inches, nor is humanity 5 feet 10 3/4 inches as a result of enculturation.
Height can be said to relate strongly to social/cultural environment- IIRC the Average height in Japan is increasing, due to a change in diet, and I suspect the same will happen across much of the pacific rim (or are people of Malaysian descent naturally small, as most of them on campus are?).
A certain potential for height is imminent in genetic coding, but it takes the right social conditions to see it throught o actuality.
Take again- the kids who worked in 18Th. C. Factories and coal mines, who grew up stunted from too much time spent in cramped conditions...