Museum, University of Nebraska State


Date of this Version



American Naturalist (1980) 116(1): 143-146. "Notes and comments."


Copyright 1980, University of Chicago. Used by permission.


For the past decade, numerous investigators have attempted to explain the plethora of genetic polymorphism found in nature (see Ayala 1976). However, few researchers have been able to document how polymorphisms have been maintained, whether the polymorphisms were genic or chromosomal. Our investigations into the maintenance of a Robertsonian chromosomal polymorphism in the plains pocket goher, Geomys bursarius major, have revealed evidence that this polymorphism is maintained by differential viabilities of the three chromosomal morphs, with the heterozygote being favored.