A new study finds that one in 13 humans have ape-like feet, as against most of them who have more rigid feet.
Researchers from Boston University in the United States carried out a study involving 398 visitors to the Boston Museum of Science. The visitors were asked to walk barefoot, and with the help of a mechanised carpet scientists observed the foot structure of those visitors.
Most of the humans are known to have rigid feet. Like chimpanzees, apes have flexible feet that help them to climb trees and move around quickly. It is not clear as to how most humans ended up getting rigid feet, with ligaments holding the bones in foot together, reported BBC.
During their study, researcher Jeremy DeSilva from Boston University and his colleague found that some of the participants have a different bone structure.
When primates lift their heels off the ground, they have a floppy foot with nothing to hold the bones in foot together. This is known as a midtarsal break and is similar to the structure found in some of the museum visitors. The participants did not realise that they had this flexibility and did not observe any difference in their speed while walking. But, they could be better at climibing trees than those with rigid feet, according to the study.
Researchers also found that the bone structure of some of the participants was similar to the one found in a two-million-year old fossil human relative, Australopithecus sediba. They hope the study will help in understanding how the fossil creature moved.
"The research has implications for how we interpret the fossil record and the evolution of these features," Tracy Kivell, a palaeoanthropologist from the Max Planck Institute for Evolutionary Anthropology, told BBC.
"It's good to understand the normal variation among humans before we go figure out what it means in the fossil record."
The findings of the study are published in the American Journal of Physical Anthropology.