The article Ecological Interpretation of Postnatal Growth at High Altitude by A. Roberto Frisancho explains the factors influencing both functional and physical growth of persons living in high altitude regions. According to the study conducted it had been established that in high altitude regions functional organs growth was fast while physical growth was a bit slow. The difference in growth rates between functional and physical in such populations was explained as a result of adaptation to the harsh conditions in the high altitude environment. High altitude regions have low oxygen levels, extreme low temperatures at times as well as high boy energy consumptions. Growth and development of humans is influenced by both the genes and the prevailing external conditions.