TASK 2 - Outline major changes in human evolution that has taken place since the appearance of hominids including possible reasons why the changes may have occurred.
There have numerous changes in human evolution that have occurred since the appearance of hominids. These changes have occurred in several different areas of the body in particular to the skull, the jaw and the pelvis. To understand concepts of evolution, one must understand natural selection. Natural selection is a process in which species adapt to their environment. Natural selection is linked to evolution as it explains change when individuals or organisms with traits have a larger survival and reproductive rate compared to other individuals in the population. These inheritable genetic traits are passed to their offspring.
The most evident and most amazing change that occurred over the period of human evolution was that of bipedal movement. Humans are the only mammals that can stand and walk on two feet, thus being bipedal. Kangaroo’s hop and balance with their tail and apes are only semi bipedal as they use their knuckles to get around. In order to achieve bipedalism many major changes had to occur to the human body. An apes pelvis is quite long and narrow and resembles the shape of a box, as opposed to the humans pelvis which is short and broad and resembles a bowl. This is in order to hold major organs. The human knee is angled towards the midline of the body. This brings the knee under the centre of gravity in order to help us stand. The spine is attached to the middle of our skull as opposed to a chimpanzee who’s spine is attached a lot further back. There is evidence that shows the Australopithecines to have been more like humans in comparison to chimapanzee’s in regards to feature of their lower limbs that relate to bipedalism. Yet, in saying this, it is clear that Australopithecines are definitely not identical to modern humans either. Bipedalism helps one live in certain conditions...