Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-09T15:44:46.847Z Has data issue: false hasContentIssue false
  • English
  • Français

Natural selection as the process of accumulating genetic information in adaptive evolution*

Published online by Cambridge University Press:  14 April 2009

Motoo Kimura
Motoo Kimura
Affiliation:
National Institute of Genetics, Mishima, Japan
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. In the course of evolution, complicated organisms have descended from much simpler ones. Since the instructions to form an organism are contained in the nucleus of its fertilized egg, this means that the genetic constitution has become correspondingly more complex in evolution. If we express this complexity in terms of its improbability, defining the amount of genetic information as the negative logarithm of its probability of occurrence by chance, we may say that genetic information is increased in the course of progressive evolution, guided by natural selection of random mutations.

2. It was demonstrated that the rate of accumulation of genetic information in adaptive evolution is directly proportional to the substitutional load, i.e. the decrease of Darwinian fitness brought about by substituting for one gene its allelic form which is more fitted to a new environment. The rate of accumulation of genetic information is given by

where Le is the substitutional load measured in ‘Malthusian parameters’.

3. Using Le = 0·199, a value obtained from the application of the ‘principle of minimum genetic load’ (cf. Kimura, 1960 b), we get

It was estimated that the total amount of genetic information accumulated since the beginning of the Cambrian epoch (500 million years) may be of the order of 108 bits, if evolution has proceeded at the standard rate.

Since the genetic information is transformed into phenotypic information in ontogeny, this figure (108 bits) must represent the amount of information which corresponds to the improved organization of higher animals as compared to their ancestors 500 million years back.

4. Problems involved in storage and transformation of genetic information thus acquired were discussed and it was pointed out that the redundancy of information in the form of repetition in linear sequence of nucleotide pairs within a gene may play an important role in the storage of genetic information.

Type
Research Article
Information
Genetics Research , Volume 2 , Issue 1 , February 1961 , pp. 127 - 140
Copyright
Copyright © Cambridge University Press 1961

References

REFERENCES

Crick, F. H. C., Griffith, J. S. & Orgel, L. E. (1957). Codes without commas. Proc. nat. Acad. Sci., Wash., 43, 416–421.CrossRefGoogle ScholarPubMed
Crow, J. F. (1958). Some possibilities for measuring selection intensities in man. Hum. Biol. 30, 1–13.Google Scholar
Elsasser, W. M. (1958). The Physical Foundation of Biology. London: Pergamon Press.Google Scholar
Fisher, R. A. (1930). The Genetical Theory of Natural Selection. Oxford: Clarendon Press.Google Scholar
Haldane, J. B. S. (1949). Suggestions as to quantitative measurement of rates of evolution. Evolution, 3, 51–56.Google Scholar
Haldane, J. B. S. (1957). The cost of natural selection. J. Genet. 55, 511–524.CrossRefGoogle Scholar
Kemeny, J. G. (1955). Man viewed as a machine. Sci. Amer. 192, 58–67.Google Scholar
Kimura, M. (1960 a). Genetic load of a population and its significance in evolution. (Japanese with English summary.) Jap. J. Genet. 35, 7–33.Google Scholar
Kimura, M. (1960 b). Optimum mutation rate and degree of dominance as determined by the principle of minimum genetic load. J. Genet. 57, 21–34.Google Scholar
Lerner, I. M. (1959). The concept of natural selection: A centennial view. Proc. Amer. Phil. Soc. 103, 173–182.Google Scholar
Morton, N. E., Crow, J. F. & Muller, H. J. (1956). An estimate of the mutational damage in man from data on consanguineous marriages. Proc. nat. Acad. Sci., Wash., 42, 855–863.CrossRefGoogle ScholarPubMed
Muller, H. J. (1929). The method of evolution. Sci. Mon., N.Y. 29, 481–505.Google Scholar
Muller, H. J. (1935.) Out of the Night. New York: Vanguard Press.Google Scholar
Muller, H. J. (1958). Evolution by mutation. Bull. Amer. math. Soc. 64, 137–160.CrossRefGoogle Scholar
Schmalhausen, I. I. (1958). Control and regulation in evolution. (Russian with English summary.) Bull. Soc. Nat. Moscow, 63, 93–121.Google Scholar
Simpson, G. G. (1944). Tempo and Mode in Evolution. New York: Columbia University Press.Google Scholar
Sueoka, N. (1959). A statistical analysis of deoxyribonucleic acid distribution in density gradient centrifugation. Proc. nat. Acad. Sci., Wash., 45, 1480–1490.CrossRefGoogle Scholar
Sueoka, N. (1960). Some genetic and evolutionary considerations on the base composition of deoxyribonucleic acids. (In press.)Google Scholar
Yčas, M. (1958). The protein text. Symposium on Information Theory in Biology, pp. 70–102. London: Pergamon Press.Google Scholar