Anthers and pollen from corn, Zea mays L., expressing Bacillus thuringiensis (Bt)-derived protein frequently fall onto common milkweed, Asclepias syriaca L., growing in and near corn fields. Previous studies have shown that, alone, Bt anthers do not pose a significant risk to the monarch butterfly, Danaus plexippus L. To examine how exposure to a combination of Bt anthers and pollen affects lar...

Exposure to temperatures above 29?C has been shown to be detrimental to the de velopment of Monarch Butterfly (Danaus plexippus L.) (Lepidoptera: Nymphalidae) larvae, while it has been assumed that temperatures above 33? are lethal. However, the details of larval sensitiv ity to high temperatures are not clearly understood. We examined the effects of different lengths and timing of high-tempera...

When facing certain problems in science, engineering or technology, it is not enough to find a solution, but essential seek and the best possible solution through optimization. In many cases exact optimization procedures are applicable due great computational complexity of problems. As an alternative optimization, there approximate algorithms, whose purpose reduce by pruning some areas problem ...

Migrants of the eastern North American population of the monarch butterfly, Danaus plexippus, are often subjected to subzero temperatures, heavy dews and frost in late September and October during the autumn migration to overwintering sites in Mexico. Adults of this generation had the capacity to rapidly increase their cold-hardiness. A chilling period of 1 h at +4OC before exposure to -4OC for...

North American monarch butterflies (Danaus plexippus) undergo a spectacular fall migration. In contrast to summer butterflies, migrants are juvenile hormone (JH) deficient, which leads to reproductive diapause and increased longevity. Migrants also utilize time-compensated sun compass orientation to help them navigate to their overwintering grounds. Here, we describe a brain expressed sequence ...