Baer, Mozella (2012) Theories and mechanisms of evolution. White Word Publications, Delhi, India. ISBN 9788132342410
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Abstract
Evolution (also known as biological or organic evolution) is the change over time in one or more inherited traits found in populations of organisms. Inherited traits are particular distinguishing characteristics, including anatomical, biochemical or behavioral characteristics, that result from gene-environment interactions. Evolution may occur when there is variation of inherited traits within a population. The major sources of such variation are mutation, genetic recombination and gene flow. Evolution has led to the diversification of all living organisms, which are described by Charles Darwin as endless forms most beautiful and most wonderful. Two processes are generally distinguished as common causes of evolution. One is natural selection, a process in which there is differential survival and/or reproduction of organisms that differ in one or more inherited traits. Another cause is genetic drift, a process in which there are random changes to the proportions of two or more inherited traits within a population. In speciation, a single ancestral species splits into two or more different species. Speciation is visible in anatomical, genetic and other similarities between groups of organisms, geographical distribution of related species, the fossil record and the recorded genetic changes in living organisms over many generations. Speciation stretches back over 3.5 billion years during which life has existed on earth. It is thought to occur in multiple ways such as slowly, steadily and gradually over time or rapidly from one long static state to another. The scientific study of evolution began in the mid-nineteenth century, when research into the fossil record and the diversity of living organisms convinced most scientists that species evolve. The mechanism driving these changes remained unclear until the theory of natural selection was independently proposed by Charles Darwin and Alfred Wallace in 1858. In the early 20th century, Darwinian theories of evolution were combined with genetics, palacontology, and systematics, which culminated into a union of ideas known as the modern evolutionary synthesis. The synthesis became a major principle of biology as it provided a coherent and unifying explanation for the history and diversity of life on Earth.
| Item Type: | Book |
|---|---|
| Subjects: | Q Science > QH Natural history > QH301 Biology |
| Divisions: | Electronic Books |
| Depositing User: | Esam @ Hisham Muhammad |
| Date Deposited: | 02 Jan 2023 02:08 |
| Last Modified: | 02 Jan 2023 02:08 |
| URI: | http://odlsystem2.utm.my/id/eprint/3880 |
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