Genetics of Natural Populations XXXV A Progress Report on Genetic Changes in Populations of Drosophila pseudoobscura in the American Southwest
Dobzhansky T, Anderson WW, Pavlovsky O, Spassky B, Wills CJ. 1964. Genetics of Natural Populations XXXV A Progress Report on Genetic Changes in Populations of Drosophila pseudoobscura in the American Southwest. Evolution. 18(2):164-176
Changes in the relative frequencies of the third chromosomes with different gene arrangements have been observed between 1940 and 1963 in the populations of Drosophila pseudoobscura in all localities in California in which samples were taken during this time period. In most localities, the changes occurred in the same direction, although in some localities they took place earlier or more rapidly than in others. The causes which bring about the genetic changes are still obscure. The massive use of pesticides in California agriculture is a possibility which deserves serious consideration; if this cause were confirmed, it would follow that even the apparently most untouched environments in California have been polluted by human activities. Another possibility is that the changes arose because of the emergence of novel adaptive gene complexes, owing to mutation or to gene recombination, and to rapid spread of such gene complexes over extensive territories. Further observations and experiments are needed to elucidate the causation of the evolutionary changes observed in this apparently quite "wild" species of Drosophila. This is part of a long series of articles, spanning about four decades, concerning the genetics of free-living populations of a desert species of fruit-fly (Drosophila pseudoobscura). The original populations studied are from similar environmental conditions, in mountain forests of the Death Valley region, but isolated from each other. This part of the study compares 1963 data from Death Valley and other locations with earlier data to help determine how confined or widespread are certain "changes in the relative frequencies of gene arrangements of third chromosomes...."
- Type
- Journal Article
- Authors
- Dobzhansky, Theodosius; Anderson, Wyatt; Pavlovsky, Olga; Spassky, Boris; Wills, Christopher
- Units
- CHIS , DEVA
- Keywords
- Absence (Biodiversity), Animal Studies, Death Valley National Park CA NV, Distribution (Biodiversity), Drosophila pseudoobscura (Diptera: Drosophilidae), Genetic Studies, insect survey, Presence (Biodiversity), Santa Cruz Island Channel Islands National Park CA, Taxa Links To Datasets, Taxa Links To References, Terrestrial Invertebrates