Human Evolution Essay
Role Of Tools In Human EvolutionAccording to archeological and physical record, tool use has had an enormouseffect in the transformation of proto humans into modern humans. What stimulatedtool use was the proto humans intrest in new and easier ways to do things. Withthe introduction of tools, body morphology changed and reproductive fitnessincreased. Evolution did not happened over night. It took 4.5 million years forhumans to get where they are today. Scientists have concluded that about 3.5million years ago, there was the first proto human.
A proto human resemblesextinct hominid populations that had some but not all the features of a modernhomo sapien. Such features were prolonged moments of bipedality, change in thepelvis and the reduction of the sagittal crest. (Diamond 1992 pg 34) In orderfor this proto human to evolve into a human, it needed tools. Some of the toolsmight have been discovered by accident or by early creative geniuses? The waythey discovered the tools is unknown, but the changes the tools made were to thephysical morphology and the body behavior.
They began to walk upright, gatheredsupplies, cut food, and used weapons.(Diamond 1992 pg. 40) About 3 million yearsago, after generations of learning how to use these tools, the hominid came outof the trees, and stayed mostly on the ground. The animal had an abundance offood and water and lived in a population of; on the ground proto-human animals.
Some adapted to ground life and started to become bipedal, but more than half ofthem stayed on all fours. The bipedal hominids vision increased, making it ableto see and do more. It obtained the ability to use weapons more effectively andefficiently because it had arms with agility. It found all the good meat andvalued resources then eventually took over the whole community. Soon after thebipedal creatures gained control the hominids on four legs die off, preciselybecause they could not evolve quickly enough and produce healthy, if any,offspring. The bipedal community grew into the hundreds and thousands. Tough,healthy, and agile hominids, the strong survived and the females producedhealthy offspring which is called reproductive fitness. The mouth became smallerand the brain increased in size. More brains equaled better tools, which lead toa faster, more efficient evolution.(Diamond 1992 pg 12) According to the boneand fossil evidence that I have learned, this is my interpretation how evolutionmight have happened. When a species develops tools, many things can a willchange. The definition of a tool is, performing or facilitating mechanicaloperations.(Websters Ninth New Dictionary) Take for instance a hominid thatwalks on all four limbs. How easy would it be for a hominid, without agile arms,to mechanically operate a tool? It would be very difficult. This type ofarboreal hominid, probably lives in a tree, swings from the branches, vision isnot great, and is mostly a vegetarian. After the proto human began to walk ontwo feet there hands became free and moveable. Now give this hominid a sharpstick or a blunt object, practice as how to properly use it, and pg 3 maybe armagility. Then over time (about 3 to 2.5 mya) the animal becomes a hunter, beingable to strike a predator, protect, and gain control over resources. In themovie 2001 Space Odyssey,(Anthropology 100 9/5/97) Stanley Kubrick gives hisinterpretation on how we evolve. The movie shows groups of stem-primate typecreatures who represent early proto-human communities. The creatures begin toexplore their environment finding resources and developing new ways to dothings. The communities battled other primate communities for the naturalresources in their environment. One of the primates begins to break some objectswith a bone it picked up. The primate then realizes that this bone can do majordamage. When one community learns to use bones as weapons, then that group cantake over the resources in a certain area and be selected for, which increasesreproductive fitness. This scenario could have happened but the truth is nobodyknows exactly how and why things turned out the way they did. Not just hominidsuse tools. Wood-peckers, vultures and sea otters are among the other animalspecies that evolved by using tools to capture food, but these creatures are notas heavily dependant as we are.(Diamond 1992 pg 36) Without tools evolutionmight have taken much longer. Tools had a major affect on teeth, hair, behavior,and even language.(Diamond 1992 pg 12) When developing and using tools, thespecies takes control over the environment and makes it work for them. One majorchange in the physical aspect of evolution is the morphology of the body. Proofof this came from the discovery of Lucy, the 2.5 million year old homo- pg 4erectus, half monkey half human.(Haviland Eighth Edition pg 140-141) The headgrew so the brain could expand, allowing hominids to think and create new tools.
The mouth became smaller and teeth turned into herbivore teeth, enabling speechto develop. The widening of the pelvis was a major and critical change, itallowed the animal to walk on two feet. This change in the pelvis allowed allproto-humans to stand at long periods of time, making it more free and tallerwhich increased vision. Having the features of better vision and maneuverabilitymade it easier for the hominids to control the environment instead of lettingthe environment control them. Being able to control the environment leads tobetter food, healthier bodies, better reproductive fitness and increases thequality of life. If you think about how primitive early hominids were and youlook at modern day humans. How could a bone or stick make so much of a change inour bodies? The whole process is amazing and until science gets the whole story,we may never know the whole truth about how tools shaped our lives today. Whowould have thought that a 0.1 percent difference in DNA could have made such achange? (Diamond 1992 pg 54) One thing is for sure, without tools evolutionwould have taken much longer. pg 5Bibliography1. Haviland, Anthropology Eight Edition. Harcourt Brace, 1997 2.Diamond,Jared The Third Chimpanzee. HarperPerennial. 1992 3. Various Internet sites