Human organism represents a complex structure consisting of organs that interact in such a way that humans can live, breathe and perform all the functions that they need. But the organs as we can see them now (see Figure 1) haven’t always been the way they are now. In order to create such a system, thousands of years of evolution were required, which allowed people to have such a system of organs that would perfectly suit the environment and respond to its main factors in optimal way.
In order to clearly see the evolution of human body, it is convenient to analyze its differences from the body and organism of Neanderthals, who are the direct ancestors of the modern humans (see Figure 2). As it is seen from the picture, there are a lot of changes, which is first of all explained by the fact that the world Neanderthals lived in and our world are completely different. So, the way our bodies changed within this time is really fascinating. Below analysis of the main and most important changes will be presented.
Major changes took place in the head. First, Neanderthals had much more prominent brow ridges, than we have now. Their scull was larger, especially in length, as in the back they had a prominent bulge, which is called occipital bun. The face was larger in the middle part, nose was bigger, but there was no such pointed chin as we have today. All these traits helped Neanderthals to hunt and live in the nature in the best way for them. It is also necessary to mention that the brain was about the same size as that of the modern people with the same organization.
Large heads and stocky bodies helped Neanderthals survive in the cold climates, which is why it is clear why modern people have a changed form of skeleton – due to the technological progress and evolution of production, we have gained a lot of helpers that allow us to live without hunting and resisting severe climates. Thus, high density and thickness of leg bones also added to the Neanderthals’ greater necessity of long walking and running. In order to be able to hunt and gather food, their arms were also shorter, than modern people have today.
Thus, due to long process of evolution, today we have the systems of organs that are perfectly suited for today’s environment and way of living. Modern approaches in physiology distinguish between 10 systems of organs, each of them performing its own functions and interacting in such a way that a perfect balance is maintained. There is no such system in the organism that can work in isolation. Nervous system consists of peripheral and central nervous systems. The brain, which is one of its parts, is responsible for emotions, thoughts, sensory processing, etc. The circulatory system consists of the heart and blood vessels. It is a transportation system of the organism, as it transports different particles from one system of organs to another. Among the other systems of organs in the body there are musculoskeletal, respiratory, integumentary, gastrointestinal, reproductive, urinary, endocrine and immune.
References
Häggström, M. (2009). [Graph illustration of human anatomy]. Selection of organs in human anatomy. Retrieved from http://en.wikipedia.org/wiki/File:Man_shadow_anatomy.png
Boyd, R.S. (2009). How broken arm led scientists to genome of Neanderthals. Retrieved from http://www.mcclatchydc.com/2009/02/12/62068/how-broken-arm-led-scientists.html.
