Trends are everywhere, and in human evolution can take the form of many things, such as the reasons for divisions of species, morphological patterns (or patterns concerning how things change), and physical changes over time. Three major developments in the history of human evolution are bipedalism, an emphasis on tool use and technology, and the evolutionary trends pertaining to what changes and what simply dies out.
Bipedal Movement:
Modern humans are unique in the primate world because of their bipedal movement. That is, they walk on two feet instead of four. The earliest known primates to walk on two feet were Ardipithecus and Australopithecus, who lived anytime between 3.0 and 3.9 million years ago. These species often lived on the fringes of forested areas, gradually moving closer to the wide open grassland plains of Africa. These early hominids will eventually evolve into the modern Homo sapien, or humans.
Bipedalism affects many parts of the body, including the neck, skull, rib cage, pelvis, and limbs. So it is easy to imagine why the process of becoming bipedal creatures had taken millions of years. The rib cage has to be reshaped into a cone-like shape, the pelvis bone becomes shaped like a basin (to hold and support all of the internal organs), and the lower limbs lengthen and angle inwards. All in all, the end result is that a human’s major structures are all stacked on top of each other, each supporting the next feature up.
In the modern human body, evolution has created upright bipedal walking as simply a habitual and obligatory form of transportation.
Use and Improvement of Tools
A second trend is the human ancestor’s tendency towards the use and improvement of tools, ultimately used to manipulate the environment around them. In fact, tools are what separates the genus Homo from earlier hominid genus’s. The oldest known tools, known as Olduwan tools, originated in Africa with early Homo erectus. Acheulean tools, the improved result of Olduwan tools, were also originated in Africa. Much later, the Homo sapien species were much more involved with tools in their survival than their contemporaries, the athletic Neanderthals, and that reliance on tools likely enable their survival while the Neanderthals went extinct.
Dead-ends and Extinct Evolutionary Branches
In the evolution of humans, the formation not linear, but more like the growing and splitting branches of a tree. It is full of either “dead-ends” (or extinct branches of evolution) or “follow-throughs” (branches that have changed and evolved into a different genus or species). When viewing species, dividing them, and deciding what precedes and follows what other species, it is important to remember to view each species holistically, or as only a part of the whole history of evolution, and take all the facts into consideration.
Today, the modern human walks upright everywhere he or she goes, uses tools constantly to improve daily life, and as a species we have ended at one final branch, a branch that as of yet is successful in its survival and control of its environment.
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