SPECIATION OF EVERSMAN AND MONGOLIAN HAMSTERS (ALLOCRICETULUS, CRICETINAE): EXPERIMENTAL HYBRIDIZATION

摘要

Contrary to preexisting concepts based on morphological and karyological data on the impossibility of hybridization between hamster species of the genus Allocricetulus (A. curtatus and A. eversmanni), F-1 hybrids in both combinations, as well as backcrosses, were obtained for the first time. Some restrictions of hybridization between females of A. eversmanni and males of A. curtatus were detected. The analysis of synaptonemal complex in the hybrids produced by crossing a female of A. curtatus with a male of A. eversmanni showed that a significant portion of the cells was subject to arrest and selection at the stage of meiosis prophase I. Nevertheless, some spermatocytes still generate viable spermatozoa. Thus, the possibility of hybridization in the laboratory between two Allocricetulus species with different numbers of chromosomes may testify to a relatively low divergence between them.