Why the human is shaped like it is.

As is often mentioned human beings, or Homo Sapien sapiens, are most closely related to the Great apes. The Great Apes including Chimpanzees, Gorillas, and Orangutangs. Modern humans share many similarities to them still, many people saying that they feel an almost human presense inside these animals.

The main difference between humans and the Great apes is our posture. Humans stand upright and this has several benefits. Living on the African savanna our ancestor species were able to spot danger from far away as well as food or water resources from much further than our competitor species. By standing well above the height of grasses they were able to survey much more of an area and exploit its resources.

Being bipedal we also gain the benefit of long distance endurance. It is not often noticed but people are capable of covering much larger distances using less energy than most other animals. Being omnivores, our ancestors probably sent out hunting parties that basically just had to chase animals until they no longer had enough energy to escape the hunters spears. Even today there are cultures which still use this form of hunting.

Standing upright also aided in the cooling of the pre-human body. With the chest facing outward instead of toward the ground more surface area of the body is available to dissipate heat through sweating. Or even obsorb light for warmth or vitamin D synthesis.

With the unique trait of walking on two legs combined with their omnivorous diet. Pre-humans and early humans had a distinct advantage. Yet it was not enough. As time went on brain capacity increased. A smarter omnivorous biped could make even more advantage of its surroundings. Remembering much larger territories and the locations of springs and patches of edible material. Eventually these creatures became the rulers of their domain.

While there is no widely accepted theory as to why man became a "naked" ape, that is a mostly hairless variety of ape. It may have made dealing with the climatic changes going on throughout our history less of a problem and allowing us to spread to almost every continent of our planet and establishing our dominance over the other species.