SELECTIVE MECHANISMS IN BACTERIA1
This extract was created in the absence of an abstract.
Excerpt
The objective in population genetics is to reconstruct the possible, or more rarely the actual, sequence of events in the evolution of organisms in terms of changes resulting from the interplay of mutation and selection. The possibility of entirely succeeding in this is of course dependent on a valid and complete assessment of the attributes of the genetic systems involved. Failing in this, we may empirically examine the genetic constitution of populations before specifying any precise basis for the variability observed. The non-sexual bacteria offer good opportunities along these lines, because the immediate source of genetic variability resides in the capacity of the existing genotype to mutate, and not in the emergence of recombinant types. In other words, the reservoir of variability is not concealed, but is directly represented by the components of heterogeneous populations.
By selection we shall understand those factors other than mutation which influence the frequencies of...
Footnotes
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↵1 This work was supported in part by an American Cancer Society grant recommended by the Committee on Growth of the National Research Council and by a research grant from the Division of Research Grants and Fellowships of the National Institutes of Health, U. S. Public Health Service. The authors are grateful to Dr. Amos Norman for his help in formulating the equations.
