Page "Pygmy peoples" Paragraph 4

Various theories have been proposed to explain the short stature of pygmies.

Some studies suggest that the short stature of pygmies could be related to adaptation to low ultraviolet light levels in rainforests .< ref >.

) Other evidence points towards unusually low levels of expression of the genes encoding the growth hormone receptor and growth hormone relative to the related tribal groups, associated with low serum levels of insulin-like growth factor-1 and short stature.