Human Evolution

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Phylogenetic Trees 

Each phylogenetic tree represents a different interpretation of human evolution. Firstly in the actual structure of these two phylogenetic trees, it can be seen that figure one provides a very linear progression of human evolution in steady, constant phases of evolution and extinction. The second chart however presents a more complex inerpretation and arrangement of its data, with not only more species but far greater periods of temporal overlap. The second figure gives a larger span of time for human evolution by beginning at the 6 million mark, figure 1 however starts at the 5 million mark and therefore reveals a less effective tree of human evolution. Chart 2 provides three possible direct ancestors to Homo Ergaster, these being Homo Rudolfensis, Homo Habilis as well as one unknown or missing link. In regards to unknowns, tree one prefers to provide few missing links by only providing two, one of which is not directly related and therefore is not of great importance to modern humans. Figure 1 prefers instead to use physical evidence of evolution, such as fossils as opposed to hypothezing or predicting the incidence of unknown entities. This could reflect upon the importance placed on physical evidence as opposed to inferring at the time. Tree two on the other hand provides a total of five missing links, two of which are provided as direct ancestors to Homo Ergaster, which is itself a direct descendant of Homo Sapiens. The second figure provides two additional species as close ancestors of the original hominid, Ardipithecus Ramidus, these being , Orrorin Tugenesis and Sahelanthropus Tchadensis. This is an interesting addition and serves to add depth and further complexity to the phylogenetic tree in figure 2. This also reflects the acceptance of educated inferences in the world of phylogenetics at the time this tree was created.

Question 2. - Table - Humanoid Primates

Brain SizeFace length/widthJaw sizeTeethBrow...
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