PHYSICAL AND SOCIAL SIMILARITIES AND DIFFERENCES BETWEEN HUMANS AND PRIMATES
A primate is a mammal of order which contains simians. Primates arose from ancestors that lived in the trees of the tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment. All but a few primate species remain at least partly arboreal.
It has been historically difficult for people to accept that we are in fact just another primate species with African origins and that we differ physically only in degree from some of the others. The similarities can be seen throughout our bodies. For instance, humans and the African apes all lack external tails and have hands with a thumb that is sufficiently separate from the other fingers to allow them to be opposable for precision grips.
Humans are also sexually dimorphic –males are 5-10% larger on average and have greater upper body muscular development. Like chimpanzees, they are omnivores. We kill other animals for food in addition to eating a wide variety of plants. Internally, our bodies are even more similar to the great apes. We have essentially the same arrangement of internal organs and bones. We share several important blood types. In both species the rib cage is broad and extends past vertebral column. They both have scapulae on their back and shoulder joints oriented to the sides. About 98.5% of the genes in humans and primates like chimpanzee are identical.
The differences between humans and primates are largely a result of our habitual bipedalism. Humans showed evidence of bipedalism while apes remained quadrupeds. A number of changes in our bodies were related to the evolution of this form of locomotion. Unlike apes, our arms are relatively short and weak compared to our legs. Humans showed a reduction in their dentition (small canine teeth) as compared to that of apes. The modern human brain is three times larger in volume than those of the...