So Where Did Man Come from Anyway? (Fact Extrapolation from Research)
(image available in print form)
Hominid Species Time Line- Washington State University
In order to present my students with a sense of time and evolution of man, I will ask them to glue a copy of this graphic time line in their journals, introduce vocabulary such as evolution, archeology, DNA, and genetics, and pose several of the travel log questions. Using this website http://www.wsu.edu:8001/vwsu/gened/learn-modules/top_longfor/timeline/timeline.html
we will read, note take, and discover the answer to: So where did we come from anyway? The answer to this question will take them on a wild ride through archeology, geography, genetics, mathematics, industry, religion, anthropology, astronomy, meteorology, literature, politics, social stratification, and even to a time when man wasn't man as we know him today. Using Valerie Hansen's Voyages in World History (Chapter 1) as well as the website:http://www.mnh.si.edu/anthro/humanorigins/ha/ances_start.html), this is what I expect them to extrapolate.
Two species, humans and chimpanzees, appear to have descended from a lost species some 7 million years ago in central Africa. This is why the
DNA
, the genetic material found in the nuclei of cells in both humans and chimpanzees, overlaps about 98.4 percent of the time. Archeology is the science by which we study past human life and culture by the recovering and examining the remains of material evidence, such as graves, buildings, tools, and pottery. Through this study and many others, scientists have discovered much about the origins of man.
Hominids
, the term attributed to all humans and their ancestors, left Africa almost 2 million years ago and very slowly evolved into
Homo sapiens sapiens,
(genus-Homo, meaning "person:; species-sapiens, meaning "intelligent"; and sub-species-sapiens) also known as modern man. This growth, development, and change is described scientifically as evolution.
Evolution
is the process by which all life came to be and by which life changed from one form into another. In order for change to be activated, a
natural selection process
occurs. Most notable for the identification of this natural selection process was the 19th century scientist, Charles Darwin. He observed the variations or genetic mutations that exist within a species and determined that certain variations increased the likelihood that an individual would survive. We call this survival of the fittest. Survival meant the reproduction of more offspring who would also carry the same advantageous or valuable variants. Natural selection acts on the phenotype, or the observable characteristics of an organism. This process of hominid change extended over millions of years and continues today. Our oldest ancestors belonged, not to the genus, Homo, but rather to
Australopithecus
, a genus whose main characteristic was
bipedalism,
the walking upright on two feet. Paleontologist John de Vos from the Naturalis Museum in Leiden, the Netherlands, explains it this way:
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For the Australopithecus, eating meat was not so much a choice, as a necessity caused by evolution. Three million years ago a long drought occurred in eastern Africa, the cradle of humanity. The rain forest turned into savannah. Then two things happened at once; Man started walking upright and eating meat. ´Australopithecus had to travel greater distances on the Savannah, which prompted him to walk upright. This cost more energy, which is easier to obtain from meat than from vegetable matter. 'On top of that, there was less food to find on the Savannah than there was in the jungle. They had no choice.
The next genus that actually survived (because some did not) was
Homo habilis,
whose defining characteristics were the making of simple tools, ones from chipped stones used to scrape meat from bones, and also a diet of available fruits and vegetables. About 1.9 million years ago, a brain, double the size of earlier hominids, appeared in
Homo erectus.
These ancestors
moved about with greater ease migrating from Africa to Asia, arming themselves with axes, and probably using simple boats. Homo erectus was also believed to have control over fire, with several archeological sites providing evidence of charred wood in different layers of earth. Having the ability to use fire allowed our ancestors to cook meat much more easily thus providing the body and brain with more protein and strong development. Homo erectus ventured into Europe which was off limits up to this point due to harsh conditions. Fire and meat played a part in this journey. By 500,000, B.C. archaic
Homo sapiens
gradually, and in parallel to Homo erectus, emerged. The advanced thinking of humans living in Europe during the Paleolithic Period, also known as the late Stone Age, allowed
Cro Magnon Man
to take great strides in almost every area. They could hunt for different things during different seasons, build better housing and advance better clothing. Art was found on cave walls. From here Homo sapiens began to spread across Eurasia and Australia.
By 100,000 B.C. we see evidence of a belief in
religion,
a belief in
a divine power that controlled the environment and guided or proscribed their lives. The dead were buried but language and writing were not in place. It is thought that speech actually became part of the human existence around 100,000-50,000 B.C. although the
larynx,
the human voice box, appeared about 50,000 years earlier. It is difficult to know this for certain for what evidence is there of human speech?
Because man was able to hunt much more effectively and efficiently, he was able to move about more freely as well. Australia was one such place homo sapiens traveled to, although how they got there is not known. Scientists believe that some sort of water raft or boat was used but there is no evidence of this mode of transportation. While there, they moved inland because a burial site has been found in Mungo. Mungo Man has been buried and the site covered with red orcher powder, while a short distance away, Mungo Woman's charred remains have been found. This evidence of cremation suggests that they hoped their souls would travel to the next life. It is thought that by 25,000 B.C. all other species died out leaving Homo sapiens as our sole human species on earth. Today, much of our dating from archeological sites depends on
Carbon- 14,
an isotope found in organic material with a half life of 5700 years that can be used to determine the age of an archeological sample.
