The Evolution Of Human Behavior Essay Research — страница 2
optimistic view of human nature. It proposes that humans are cooperative by nature, with selfishness arising as a result of private property, class, or reaction to selfishness of others. The opposite view, advocated by people like Thomas Hobbes and Emile Durkheim is called the pessimistic view of human nature. It suggests that humans are selfish and antisocial by nature. People become civilized only through exposure to culture; without social and governmental controls, cooperation would not occur. Natural selection seems to favor the pessimistic view of human nature as the more correct view. All living things, including humans, are born selfish. After that, they remain selfish throughout their entire lives. Organisms behave the way they do because they want to better their chances of propagating their genes. To understand why insist so vigorously on passing on their genes, one must look back to the time on earth leading to the creation of life. The following description, explains how selfish came about. Richard Dawkins’ account of the sequence of events in The Selfish Gene is perhaps the most concise and easy to understand of all acounts given thus far. Before the existence of life, the earth primarily consisted of randomly scattered atoms and small molecules. Darwin’s theory shows how these strewn out, “unordered atoms could group themselves into ever more complex patterns until they ended up manufacturing people” (Dawkins 13). The laws of physics and chemistry say that a group of atoms which aggregate into a stable structure will tend to remain stable, unless some outside force destabilizes the molecular interactions. In other words, atoms which happen to come together in a particularly stable structure will persist longer than atoms which do not fall into any type of stable configuration. Experiments have shown that mixtures similar to those abundant in pre-life earth (these mixtures consisted mostly of molecules of water, carbon dioxide, methane, ammonia, and other organic and inorganic compounds) produce amino acid residues when exposed to ultra violet light and electric sparks. Since amino acids still exist today, one may assume that these molecules posses high stability, especially when compared to other molecules in pre-life earth. Because amino acids form proteins, their presence generally foretells the coming of life. Once synthesized, these proto-amino acids proceeded to drift through the earth’s primordial ooze. In the process, their chemical properties were altered by other stray atoms and molecules also in the ooze. One of these chemical changes eventually ended up producing a proto-amino acid with the unique ability to replicate itself. The mechanism for replication probably involved some sort of affinity between molecules with opposite properties. This is analogous to the positive and negative poles of magnets which attract each other. In the case of the molecules in the ooze, substances protruding from their surface had a specific affinity for atoms containing the opposite substance. A new molecule was constructed once the original molecule attracted enough atoms in this manner. Thus, one molecule served as a template for the building of a complementary molecule. After joining, these two molecules then separated to once again expose their surface substances, which then went on to attract other atoms building even more molecules. This replication also exist in DNA. The DNA molecule consists of two complementary strands running anti-parallel to each other. When these strands separate from each other, their nitrogenous bases become exposed. The two separated strands then each base pair with complementary strands resulting in two new DNA molecules. Here, the surface substances are the nitrogenous bases adenine, guanine, cytosine, and thymine. Adenine base pairs with thymine, while cytosine pairs with guanine. Like the DNA molecules of today, the replicating molecules of pre-life earth occasionally made mistakes during replication. This resulted in mutations which often altered the characteristics of the molecule. Some of these changes hindered to the molecule’s ability to further replicate, while other changes actually enhanced these abilities. Those molecules which received detrimental mutations were unable to further replicate, and ceased to exist. On the other hand, those molecules which gained enhanced replicating abilities became more abundant in the primordial ooze. Those molecules that were not lucky enough to receive the enhanced replicating abilities were driven into non-existence by the enhanced replicators who were perhaps able to out compete them for the necessary building block molecules in the ooze. In
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