Evolution Of Man: Aggressive Behavior Shaped Posture For Optimal Fighting Performance
There are on-going studies focusing on the evolution of man to better understand how the different anatomical parts of the body evolved and function throughout history. In a recent study, researchers from the University of Utah was able to find a possible explanation on how feet evolved in great apes like human beings. They were able to determine that aggressive behavior played a part in shaping the posture of great apes for optimal fighting performance.
The study, published in the journal Biology Open, focused on examining how mechanics of movement, in this case of the heels of the feet, evolved throughout the course of time. In addition, the study examines how human nature plays a role in the evolution of the physiology of man.
According to the researchers, a species' body should be in its best condition to get an advantage when competing for resources or for mates. This is why certain anatomical traits have developed different functions based on the required tasks needed and for a chance of survival.
Unlike other primates, great apes which are the evolutionary cousins of human beings, heels that can support the body weight during standing, walking, or running. This posture, known as plantigrade foot posture, is a heel down posture that is shared by other animals like bears, wolverines, and some rodents and is less specialized in running but has an advantage when it comes to fighting.
When it comes to fighting, the plantigrade stance allows a greater striking force of the arms or the greater rotational force applied on the ground. In addition, these stance allows for other actions that are optimized for fighting.
In order to fully understand how the plantigrade foot stance is employed in fighting, the researchers had 12 human volunteers strike weighted pendulum. The volunteers stood on a plate that recorded the force applied on the ground as the struck the pendulum. The velocity of the strike and resistance of the pendulum to the strike was measured in order to calculate the work performed. The volunteers were also asked to strike the weighted pendulum but this time wearing fuzzy socks and standing on a sheet of Teflon.
The study found that the plantigrade stance does allow for more force to be applied when striking. And in order to survive, not only was the aggressive behavior important in developing the skills needed to live but also helped evolved anatomical traits that enable advantages when it comes to fighting.