There is a theory that humans descended from an earlier, lower form of life. There is an assortment of evidence that shows that all living creatures on Earth descended from a common ancestry. Evolution doesnt discriminate against humans. It is believed that we too are a product of an earlier predecessor. The similarities in all life are evident if you consider that every form of life builds from the same building blocks--20 essential amino acids, four nitrogen bases, and simple sugars. Each of Earths past and present forms of life are, or were composed of a combination of those building blocks called RNA or DNA. In the very beginning of life on Earth, the genetic structure ...view middle of the document...
They try to map out the path of the ancestry between organisms over the existence of the Earths history. Another essential part of the study of evolution is actually making educated predictions of the history of a species. The history of a species includes the geographical distributions and the species population over time.All of the information that follows is valid in that it has genetic and fossilized evidence to prove its merit. Some of the most important aspects that make a human different from its ancestors are the development of communication, brain function, and the ability to walk upright, which frees up the hands to embark on other tasks. Language is considered by many to be the most unique of all the human attributes.As strange as it may sound, genetically we are the most similar to that of primates as any other known living creature on Earth. The primate family includes chimpanzees, orangutans, gorillas and even humans. Other than genetic similarities, we can show other likenesses in the tissue physiology and also by comparing brains circuits in a brain analysis.Humans are a prime example of natural selection. The domination of the world by the superior present day human is what ended all similar species. The species that we dominated were our greatest competition for food, intelligence, and essentially our very existence on this planet. When we beat our predecessor, we did it in a fight for our lives, not so much as an act of violence. In many cases, Humans may have killed our ancestors in a misunderstanding, not knowing why a similar being was so much more savage and violent. We may have protected our families by attacking these beastlike creatures.The first things that we need to know are, Who were our first ancestors? Why did they evolve? What did they look like? And how did they live? Without this information, we will not know what we have arisen from.The most likely place to look for our fossilized lineage is in the environment of our closest living relatives--Africa. This is the reason that most of our archeological digs have been occurring on this continent. Of the fossils found, the skulls have been the most important because by knowing the structure of the skull, we can see how distant their relations are to us. Since one of the most significant changes is brain size and function, the brain and brain cavities provide a lot of evidence for evolutionary change. We know about brain function from fossils because sometimes, even the brain is preserved inside the fossilized skulls.Our most distant known lineage into the human path is very much similar to that of a chimpanzee. This creature was known as Australopithecus afarensis and can be dated back to 3.2 million years ago. A. afarensis was still very similar to a chimp. The brain size was no larger than ours. The finger bones were still curved, showing that it was still quite comfortable in the trees. Even though it was slightly similar, it was still v...