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| The Theory of Evolution |
The Theory of Evolution
The theory of evolution is one of the ultimate scientific theories and is the cornerstone of our understanding of life processes on Earth. As such, it is worth special consideration in the final section of this chapter.
During the age of European exploration, biological specimens were collected from all over the world. Once the specimens arrived in Europe, naturalists began the systematic classification of these plants and animals using the naming scheme proposed by Carl Linnaeus. The subtle differences between related species were the cause of much speculation. Apparently conditions in nature could lead to selective breeding of plants and animals.
The creation of whole new species via evolution was considered by a number of biologists, but initially there was no agreement as to a possible mechanism. Then in 1859, Charles Darwin published The Origin of Species. Darwin summarized the existing evidence for the evolution of life and proposed ‘natural selection’ as the mechanism that made it work. Since that time, the theory of evolution has been refined to include data and theories from a wide range of scientific investigations.
We know that species can become extinct. In fact, during the past few centuries humans have been the active agents in killing off all the members of several species such as the dodos birds, carrier pigeons, and moa birds.
We know that selective reproduction can alter the average characteristics of a species. For thousands of years farmers have applied selective breeding to obtain more productive plants and animals.
We also know that species can evolve without human intervention. One or more new versions of the influenza virus evolve each year requiring the creation of new vaccines for immunizations. One of the reasons that the AIDS virus is so difficult to treat is because it evolves so rapidly in a patient’s body that today’s treatment may not work tomorrow. In 2006 there was great concern that a new virus attacking the bird populations of the world would evolve into a contagious human form.
Evolution is more complicated than ‘survival of the fittest’, but once the necessary ingredients are understood, evolution loses much of its mystery and can be regarded as a natural part of life.
The theory of evolution is one of the ultimate scientific theories and is the cornerstone of our understanding of life processes on Earth. As such, it is worth special consideration in the final section of this chapter.
During the age of European exploration, biological specimens were collected from all over the world. Once the specimens arrived in Europe, naturalists began the systematic classification of these plants and animals using the naming scheme proposed by Carl Linnaeus. The subtle differences between related species were the cause of much speculation. Apparently conditions in nature could lead to selective breeding of plants and animals.
The creation of whole new species via evolution was considered by a number of biologists, but initially there was no agreement as to a possible mechanism. Then in 1859, Charles Darwin published The Origin of Species. Darwin summarized the existing evidence for the evolution of life and proposed ‘natural selection’ as the mechanism that made it work. Since that time, the theory of evolution has been refined to include data and theories from a wide range of scientific investigations.
We know that species can become extinct. In fact, during the past few centuries humans have been the active agents in killing off all the members of several species such as the dodos birds, carrier pigeons, and moa birds.
We know that selective reproduction can alter the average characteristics of a species. For thousands of years farmers have applied selective breeding to obtain more productive plants and animals.
We also know that species can evolve without human intervention. One or more new versions of the influenza virus evolve each year requiring the creation of new vaccines for immunizations. One of the reasons that the AIDS virus is so difficult to treat is because it evolves so rapidly in a patient’s body that today’s treatment may not work tomorrow. In 2006 there was great concern that a new virus attacking the bird populations of the world would evolve into a contagious human form.
Evolution is more complicated than ‘survival of the fittest’, but once the necessary ingredients are understood, evolution loses much of its mystery and can be regarded as a natural part of life.
