Correlating these findings with The Bell Curve, another work of impeccably objective statistical research, one would expect Jews and Eastern-Asians to be the tallest people on the planet.
Unless this study took extreme care to plot the participants' height percentiles against known averages of the various ethnicities predominant in the participants' respective bloodlines, I'd be pretty wary of taking any of these conclusions to heart.
For example: John, a 7 year old whose bloodline can be traced back to a specific region of the British Isles for 20 generations, and is more than a standard deviation taller than an average 7-year-old with the same ethnic profile, possesses an IQ that is more than a standard deviation higher than average for a 7-year old fitting that exact description.
If a coherent pattern emerges after considering a couple hundred such cases(I picked 7 year old because that's about the youngest age afterwhich IQ will not significantly change), then maybe there's something to this theory. If they're just comparing people from across the spectrum of backgrounds--backgrounds which, by virtue of evolution, will invariably favor height differently--then I think these researchers are better off getting back to their true calling:
MAKING ME DINNER
