Date of Award
Fall 1973
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Biology
First Advisor
Rasch, Ellen M.
Second Advisor
Hennen, Sally
Third Advisor
Balsano, J. S.
Abstract
A method was developed and evaluated for assessing the ploidy of individual fish by cytophotometric measurements of Feulgen-stained scale epithelial nuclei. This technique was used to examine specimens of Amazon molly, Poecilia formosa, its sympatric diploid congener, P.mexicana, putative triploid females associated in nature with P. formosa, and the laboratory-reared progeny of these triploids. The analyses showed that triploid females of the genus Poecilia occur in several different localities of the Rio So to la Marina drainage in northeastern Mexico. When mated to males of P. mexicana in the laboratory, these triploid females consistently gave rise to all-female, triploid young. One instance of triploid offspring produced by a diploid female of P. formosa was found. Alternative mechanisms are proposed to account for the origin and reproduction of triploids. The implications of these models for speciation in the P. formosa- P. mexicana breeding complex are discussed.
Recommended Citation
Strommen, Carol Arita, "Cytophotometric Evidence for the Origens and Persistence of Triploid Genomes in the Progeny of Females Associated in Nature with the Amazon Molly Fish, Poecilia Formosa (Girard)" (1973). Master's Theses (1922-2009) Access restricted to Marquette Campus. 3090.
https://epublications.marquette.edu/theses/3090