http://www.newsweek.com/why-pygmies-evolved-be-so-short-1203575

File photo. The Amazon rainforest iStock Share Tech & ScienceHuman populations living in the rainforests of Bolivia and Malaysia appear to have evolved to be short in order to navigate the dense vegetation, scientists have discovered.

People with the human pygmy phenotype are found across the globe, normally in tropical regions. Adult males are normally less than 5 feet 2 inches in height. Recent research has shown their short stature is the result of convergent evolution—where different populations evolve the same trait because of the similar environment in which they live. However, it is not entirely clear what the adaptive benefit of being so short is.