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241.
The cuticular surface of sexually mature females of the German cockroach contains a sex pheromone that, upon contact with the male's antennae, elicits a characteristic species-specific courtship behavior. This female-specific pheromone is a blend of several long-chain methyl ketones, alcohols and aldehydes, all derived from prominent cuticular hydrocarbons found in all life stages of this cockroach. We found that contact with the antennae of 5 out of 20 assayed cockroach species elicited courtship behavior in German cockroach males. The heterospecific courtship-eliciting compounds were isolated by behaviorally guided fractionation of the active crude extracts and compared to the native sex pheromone components. We identified two active compounds from the cuticular extract of the Oriental cockroach, Blatta orientalis -- 11-methylheptacosan-2-one and 27-oxo-11-methylheptacosan-2-one; the former compound was confirmed by synthesis and proved to independently stimulate courtship in German cockroach males. These compounds share common features with, but are distinct from, any of the known contact sex pheromone components. This suggests that sex pheromone reception in the male German cockroach is unusually promiscuous, accepting a wide range of compounds that share certain features with its native pheromone, thus resulting in a broad spectrum of behavioral response to other species. We propose that several characteristics of their mating system -- chiefly, absence of closely related species in the anthropogenic environment, resulting in relaxation of selection on sexual communication, and a highly male-biased operational sex ratio -- have driven males to respond with extremely low thresholds to a wide spectrum of related compounds. 相似文献
242.
Kikuchi T Miyazaki S Ohnishi H Takahashi J Nakajima Y Tsuji K 《Die Naturwissenschaften》2008,95(10):963-968
Evolution of caste is a central issue in the biology of social insects. Comparative studies on their morphology so far suggest
the following three patterns: (1) a positive correlation between queen–worker size dimorphism and the divergence in reproductive
ability between castes, (2) a negative correlation among workers between morphological diversity and reproductive ability,
and (3) a positive correlation between queen–worker body shape difference and the diversity in worker morphology. We conducted
morphological comparisons between castes in Pachycondyla luteipes, workers of which are monomorphic and lack their reproductive ability. Although the size distribution broadly overlapped,
mean head width, head length, and scape length were significantly different between queens and workers. Conversely, in eye
length, petiole width, and Weber’s length, the size differences were reversed. The allometries (head length/head width, scape
length/head width, and Weber’s length/head width) were also significantly different between queens and workers. Morphological
examinations showed that the body shape was different between queens and workers, and the head part of workers was disproportionately
larger than that of queens. This pattern of queen–worker dimorphism is novel in ants with monomorphic workers and a clear
exception to the last pattern. This study suggests that it is possible that the loss of individual-level selection, the lack
of reproductive ability, influences morphological modification in ants. 相似文献
243.
Abukmeil Reem Barhoum Ali Dher Majdi Yoshida Mitsuo 《Journal of Material Cycles and Waste Management》2022,24(1):4-11
Journal of Material Cycles and Waste Management - The situation of health-care waste in the Gaza Strip was threatening the environment and the public health due to the absence of appropriate... 相似文献
244.
Yoshida Gen Seyama Tomohiro Andriamanohiarisoamanana Fetra J. Hirayasu Hirofumi Kasai Koji Ihara Ikko 《Journal of Material Cycles and Waste Management》2022,24(1):402-409
Journal of Material Cycles and Waste Management - Conventional anaerobic digestion (AD) process was often slow and thus required a large digestion tank. Upflow anaerobic sludge blanket (UASB)... 相似文献