DISTURBANCE OF ECLOSION SEQUENCE IN HYBRID LEPIDOPTERA

Abstract

AbstractSome interspecific and interpopulation Lepidoptera and Orthoptera hybrids show a syndrome of developmental abnormalities referred to here as the “sequence effect.” In normal within population broods of Lepidoptera males develop slightly faster than females, but in crosses showing the sequence effect, females in one direction of the cross develop faster and in the reciprocal cross much more slowly than their male siblings. In some cases the environmentally induced diapause of the females may differ strikingly from that of their male siblings. Development rate and diapause in these species appear to be controlled by a sex-linked coadapted gene complex. Expression of the sequence effect may result from a loss of a species- or population-specific balance between regulatory and secretory portions of this complex, resulting in hormonal abnormalities which are more likely to be expressed in the heterogametic sex (females in Lepidoptera, males in Orthoptera).