Regulating their body temperature to prevent overheating is a burden for chimpanzees living in the African savanna
When humans started settling in more open and hot habitats during their evolution, they had to adapt to the new environmental conditions and, possibly, to develop protection against overheating and to find ways to consume enough food for their survival. An international team of scientists from the Max Planck Institute for Evolutionary Anthropology in Leipzig has studied the physiological parameters of savanna and rainforest chimpanzees in two studies and compared their water and energy budgets as well as their stress levels. They found that the stress of maintaining their body temperature is a tremendous burden on chimpanzees living in the savanna.