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Discriminating nestmates from alien conspecifics via chemical cues is recognized as a critical element in maintaining the integrity of insect societies. We determined, in laboratory experiments, that nestmate recognition in an introduced population of the Argentine ant, Linepithema humile, is modified by hydrocarbons acquired from insect prey, and that workers from spatially isolated colony fragments, each provided with prey that possessed distinct cuticular hydrocarbons, displayed aggressive behavior towards their former nestmates. Isolation for 28 days or more between colony fragments fed different prey was sufficient to prevent re-establishment of inter-nest communication for at least an additional 28 days through the introduction of a bridge between the nests. Ants possessed intrinsic cuticular hydrocarbons plus only those hydrocarbons from the prey they received during the isolation period. Colony fragments which were isolated for less than 28 days reunited with workers possessing both prey hydrocarbons. Therefore, L. humile nestmate recognition may be dynamic, being in part dependent on the spatio-temporal distribution of prey, along with physical factors permitting or restricting access of subcolony units to those prey. 相似文献
173.
David P. Bick MD Daniel F. Schorderet Paul A. Price Leslie Campbell Robert W. Huff Larry J. Shapiro Charleen M. Moore 《黑龙江环境通报》1992,12(1):19-29
We report the prenatal diagnosis of a male fetus with X-linked recessive chondrodysplasia punctata (CDPX), steroid sulphatase (STS) deficiency, X-linked Kallmann syndrome (KAL), and a chromosome deletion at Xp22.31. Biochemical analysis of bone from this case indicates that CDPX is not a defect of vitamin K metabolism. Immunocytochemical study of the brain suggests that KAL is a defect in neuronal migration. 相似文献
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In most social insect species, individuals recognize and behave aggressively towards non-nestmate conspecifics to maintain
colony integrity. However, introduced populations of the invasive Argentine ant, Linepithema humile, exhibit pronounced variation in intraspecific aggression denoting diversity in nestmate recognition behavior, which possibly
shapes their social structure and the varying levels of unicoloniality observed among these populations. One approach to better
understand differential aggression behaviors towards conspecifics and recognition cue perception and response in L. humile is to examine variation in nestmate discrimination capability among genetically distinct colonies under different social
contexts. Consequently, we investigated the dynamics of queen and worker recognition in southeastern US L. humile queenless and queenright colonies by measuring rates of non-nestmate worker and queen adoption and intercolony genetic similarity.
Aggression levels between colony pairs differed and were associated with non-nestmate worker, but not queen adoption. Adoption
of queens and workers was a function of host colony origin, while colony queen number affected adoption of queens, but not
workers, with queens more readily accepted by queenless hosts. Fecundity of adopted non-nestmate queens was comparable to
that of rejected non-nestmate and host colony queens, suggesting that queen fecundity did not affect adoption decisions. Genetic
similarity between colonies ranged from 30 to 77% alleles shared, with more genetically similar colonies showing lower levels
of intraspecific aggression. Non-nestmate queens and workers that were more genetically similar to host colony workers were
more likely to be adopted. We provide the first evidence for the role of L. humile colony queen number on queen discrimination and suggest an effect of resident queens on worker conspecific acceptance thresholds.
Our findings indicate a role for genetically based cues in L. humile nestmate recognition. However, subtle discrimination capability seems to be influenced by the social context, as demonstrated
by more frequent recognition errors in queenless colonies. 相似文献
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K. M. Shamsul Haque Philip L. Eberbach Leslie A. Weston Mike Dyall-Smith Julia A. Howitt 《Chemistry and Ecology》2016,32(2):182-200
Flooding of wetland or agricultural soils can result in substantial alteration of the pore water trace metal profiles and potentially also influence the bioavailability of other trace elements adsorbed to the insoluble oxides. Experimental microcosms were used to quantify the impact of rice (Oryza sativa) plants across an entire growing cycle on the concentrations of Mn2+ and Fe2+ in two soil types (red sodosol and grey vertosol). Two water management treatments were included: a standard flooded treatment and a saturated treatment (?3?kPa). Soil pore water profiles were established from samples collected at four sampling depths (2.5, 7.5, 15 and 25?cm) on 50 occasions. Fe2+ and Mn2+ concentrations were higher in flooded soil than in saturated soil and greatest at a depth of 7.5?cm. The presence of rice plants increased Mn2+ concentrations in flooded soils, but tended to decrease Mn2+ concentrations in saturated soils. The influence of rice plants on Fe2+ concentrations was greatest at a depth of 7.5?cm. Changes in soil pore water Fe2+ and Mn2+ concentrations due to the presence of rice plants were correlated with flowering and reproduction. 相似文献
179.
Brazner JC Tanner DK Detenbeck NE Batterman SL Stark SL Jagger LA Snarski VM 《Environmental management》2004,33(6):855-875
As part of a comparative watershed project investigating land-cover/land-use disturbance gradients for streams in the western Lake Superior Basin, we examined general relationships between landscape character and fish assemblage structure and function. We also examined the shape of those relationships to identify discontinuity thresholds where small changes in landscape character were associated with marked shifts in the fish assemblages. After completing a geographic analysis of second- and third-order watersheds in the western Lake Superior drainage, we randomly selected 48 streams along mature forest and watershed storage gradients in 2 hydrogeomorphic regions as our study sites. During the summers of 1997 and 1998, we used electrofishing to sample fish assemblages from each stream. Each of the landscape factors was significantly associated with fish assemblage structure and function based on analysis of covariance. Watershed storage was related to the greatest number of fish assemblage characteristics, but hydrogeopmorphic region and mature forest cover were strongly associated as well. The hydrogeomorphic region also mediated relationships between watershed character and fish assemblages. Discontinuity thresholds for our fish assemblages averaged 11% for watershed storage and 50% for watershed mature forest cover based on piecewise regression analysis. Although many of the landscape–fish relationships might have been manifest through effects on in-stream habitat, our results highlight the importance of management and land-use planning decisions at the watershed and landscape scales.Published online 相似文献
180.