A group of scientists from the Institute for Advanced Study in Toulouse, Harvard University, the University of Exeter and the University of California have come up with a theory that explains the low growth of pygmies living in the jungle. In their article, published in the Proceedings of the Royal Society B, scientists have suggested that shorter strides that lower humans take have an evolutionary advantage for jungle life.
Scientists have long been trying to explain the small growth of pygmies. Most pygmies are short in stature living in tropical regions such as Malaysia or the Amazon jungle. But why does nature prefer short stature for life in the jungle? Some have suggested that a smaller body is better at dissipating heat or coping better with high levels of humidity. But the truth is, nobody knows the real reason. In the new work, the researchers decided to find the answer. They first came up with a hypothesis and then ran several experiments to test their ideas.
Why are pygmies so short?
The hypothesis was that it is easier for shorter people to walk in dense jungle - tall people with longer strides have difficulty walking in dense forests. To test this idea, scientists have built models that mimic the behavior of people of different sizes making their way through the jungle. They then compared the find with real people - observing and recording how tall people and pygmies made their way through the jungles of Batek Peninsula in Malaysia and Tsiman in Bolivia.
The researchers report that both their models and their observations of people walking in the jungle are consistent with the hypothesis that shorter pygmies made their way through the jungle much better, and the reason for this was their shorter stride length. The short steps allowed the pygmies to move through the dense undergrowth much faster.
Ilya Khel