Allozymic and chromosomal similarity in two Drosophila species. (original) (raw)

Proc Natl Acad Sci U S A. 1975 Nov; 72(11): 4521–4525.

Abstract

D. setosimentum and ochrobasis are a pair of very close, partly sympatric species endemic to Hawaii island. Males of the two species differ strikingly in wing-pattern and there are altitudinal and breeding-site differences. Similarity indices have been calculated for both chromosomal (C) ald allozymic (A) variants. Within the main populations of each species both kinds of data give coefficients above 0.98. Interspecific comparison of the main populations shows 0.66 (C) and 0.79 (A). An isolated population of ochrobasis from Kohala Volcano (Ohu), when compared with setosimentum, shows 0.68 (C) and 0.98 (A). Chromosomes are thus much more sensitive than allozymes in distinguishing these species; the same is true in the case of D. silvestris and heteroneura from the same forests. These morphologically distinct species, when compared, show 0.96 (A). All four species appear to be very new in the historical sense. In one area, about 2% of wild-caught D. setosimentum/ochrobasis are interspecific hybrids although adequate samples indicate that the separate gene pools have not broken down. The specific names should be retained but the two entities are perhaps best described as quite advanced semispecies in which reproductive isolation in nature is now nearly complete.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (741K), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.


Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences