You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Analysis of Head Shape Differences Between Two Interfertile Species of Hawaiian Drosophila
Alan R. Templeton
Vol. 31, No. 3 (Sep., 1977), pp. 630-641
Published by: Society for the Study of Evolution
Stable URL: http://www.jstor.org/stable/2407527
Page Count: 12
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Drosophila heteroneura and D. silvestris are sympatric species of Hawaiian Drosophila which are very similar by electrophoretic and cytogenetic criteria, but which are very distinct morphologically. Since F1's, F2's and backcrosses may be obtained in the laboratory, Dr. F. C. Val (1977) was able to study the genetic basis of the morphological differences between these two species. This paper presents a more detailed analysis of one of the morphological characters studied by Val, namely head shape. First, a mathematical definition of shape is given so that Val's raw data on head length and width may be partitioned into a size and shape component. Next, a transformation of the data is performed that eliminates all the mean size differences between the populations studied, but preserves their shape differences. A genetic analysis is then performed on these 'size-adjusted' populations. This analysis reveals that the difference in head shape between D. heteroneura and D. silvestris is due to a polygenic system of several autosomal loci with predominately additive effects upon which is overlaid a sexual dimorphism that is most likely controlled by a sex-linked locus or loci whose expression is male-limited.
Evolution © 1977 Society for the Study of Evolution