Entomologia Croatica, Vol. 2 No. 1-2, 1996.
Original scientific paper
HIGH VITALITY VERSUS LOW FERTILITY IN ARTIFICIAL INTERSPECIFIC F₁ HYBRIDS OF BUTTERFLIES (a preliminary report)
Zdravko Lorković
; III. cvjetno naselje 25, Zagreb, Croatia
Abstract
The method of artificial mating of Lepidoptera permits crossings to be made between species which do not interbreed in nature. The haplogenomes of the F₁ interspecific hybrids are often highly compatible, so that able (in lab) specimens are produced. In spite of such a high compatibility, the hybrids are mostly infertile. Sterility is due to the inability of the F₁ hybrids to produce mature gametes, even in backcrosses. One of the causes of this reproductive incapacity is the irregular meiosis of the ripening gametes. It is due to the disturbed synapsis of the "homologous" chromosomes. The "homologous" chromosomes fail to match not so much because of the new mutations but rather because of the altered linear arrangement of the chromosome loci. It is concluded that the cumulation of discordances between homologous chromosomes, resulting in hybrid sterility, is mainly responsible for the development of reproductive isolation between emerging diversity (species), exceeding its importance in the appearance of new mutations.
Keywords
Lepidoptera; artificial mating; chromosomes; homologues; meiosis; interspecific hybrids; evolution
Hrčak ID:
284236
URI
Publication date:
31.1.1997.
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