Abstract
Selection at the population level or group selection is defined as genetic change that is brought about or maintained by the differential extinction and/or proliferation of populations. Group selection for both increased and decreased adult population size was carried out among laboratory populations of Tribolium castaneum at 37-day intervals. The effect of individual selection within populations on adult population size was evaluated in an additional control series of populations. The response in the group selection treatments occurred rapidly, within three or four generations, and was large in magnitude, at times differing from the controls by over 200%. This response to selection at the populational level occurred despite strong individual selection which caused a decline in the mean size of the control populations from over 200 adults to near 50 adults in nine 37-day intervals. "Assay" experiments indicated that selective changes in fecundity, developmental time, body weight, and cannibalism rates were responsible in part for the observed treatment differences in adult population size. These findings have implications in terms of speciation in organisms whose range is composed of many partially isolated local populations.
Full text
PDFSelected References
These references are in PubMed. This may not be the complete list of references from this article.
- Boorman S. A., Levitt P. R. Group selection on the boundary of a stable population. Theor Popul Biol. 1973 Mar;4(1):85–128. doi: 10.1016/0040-5809(73)90007-5. [DOI] [PubMed] [Google Scholar]
- Gadgil M. Evolution of social behavior through interpopulation selection. Proc Natl Acad Sci U S A. 1975 Mar;72(3):1199–1201. doi: 10.1073/pnas.72.3.1199. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Levins R., Culver D. Regional Coexistence of Species and Competition between Rare Species. Proc Natl Acad Sci U S A. 1971 Jun;68(6):1246–1248. doi: 10.1073/pnas.68.6.1246. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wilson D. S. A theory of group selection. Proc Natl Acad Sci U S A. 1975 Jan;72(1):143–146. doi: 10.1073/pnas.72.1.143. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wright S. Evolution in Mendelian Populations. Genetics. 1931 Mar;16(2):97–159. doi: 10.1093/genetics/16.2.97. [DOI] [PMC free article] [PubMed] [Google Scholar]