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The cost of mutualism in a fly-fungus interaction 总被引:2,自引:0,他引:2
The movement ability of individuals has become increasingly important to a variety of ecological questions. In this study,
I investigate how plant structure and changes in body size through development affect the movement ability of a predaceous
stinkbug, Podisus maculiventris, on three species of goldenrod (Solidago spp.) representing a wide range of surface complexities. I adapt existing techniques for quantifying movement in two dimensions
to the study of movement on natural plant structures in three dimensions. These experiments indicate that plant structure
and insect size are significant factors affecting the movement ability of P. maculiventris. Changes in movement ability due to factors of ontogeny and different habitat structures suggest that the scale of an individual’s
ambit or ecological sphere of influence may vary within its lifespan. Considering the influence of ontogeny and habitat structure
on movement ability may be useful to investigations of population dynamics, foraging behavior, and pest management.
Received: 14 July 1999 / Accepted: 23 March 2000 相似文献
3.
Recent evidence suggests that the nutritional state of male Mediterranean fruit flies, Ceratitis capitata (Wied.) (medfly), is an important influence on various components of their reproductive biology, including mating success. The objective of the present study was to examine experimentally the effect of temporary starvation on the mating success of wild male C. capitata. Males were maintained on protein–sugar or sugar-only diets, and for each diet we compared the mating success of continuously fed males versus males starved for 18 or 24 h immediately before testing. In trials conducted on field-caged, host trees, males starved for 24 h obtained only about half as many matings as fed males for both diets. However, when the starvation period was 18 h, starved males reared on the protein–sugar diet mated significantly less frequently than fed males, whereas starved males reared on sugar mated as often as fed males. Measurements of male pheromone calling and female attraction revealed that reduced mating success likely reflected the decreased signaling activity of starved males. 相似文献
4.
The lung volume, the morphometrically determined alveolar and capillary surface area, and the capillary volume of 27 dogs (weight 2.65–57 kg) all were linearly correlated with body weight. The thickness of the air-blood barrier increased only slightly with increasing body size. The structural diffusing capacity, containing these parameters, was used to estimate the gas exchange capabilities of the lung and was also found to scale in direct proportion to body size. This coincides with reports on physiologically estimated diffusing capacity but is obviously different from the interspecies slope for metabolism which scales to the 3/4 power of body weight. 相似文献
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Protein synthesis and aggregation of embryonic cells 总被引:3,自引:0,他引:3
9.
Jin-Ying Cui Han Miao Li-Hong Ding Todd C. Wehner Pan-Na Liu Ye Wang Sheng-Ping Zhang Xing-Fang Gu 《PloS one》2016,11(2)
Spines or trichomes on the fruit of cucumbers enhance their commercial value in China. In addition, glabrous mutants exhibit resistance to aphids and therefore their use by growers can reduce pesticide residues. Previous studies have reported two glabrous mutant plants containing the genes, csgl1 and csgl2. In the present study, a new glabrous mutant, NCG157, was identified showing a gene interaction effect with csgl1 and csgl2. This mutant showed the glabrous character on stems, leaves, tendrils, receptacles and ovaries, and there were no spines or tumors on the fruit surface. Inheritance analysis showed that a single recessive gene, named csgl3, determined the glabrous trait. An F2 population derived from the cross of two inbred lines 9930 (a fresh market type from Northern China that exhibits trichomes) and NCG157 (an American processing type with glabrous surfaces) was used for genetic mapping of the csgl3 gene. By combining bulked segregant analysis (BAS) with molecular markers, 18 markers, including two simple sequence repeats (SSR), nine insertion deletions (InDel) and seven derived cleaved amplified polymorphism sequences (dCAPs), were identified to link to the csgl3 gene. All of the linked markers were used as anchor loci to locate the csgl3 gene on cucumber chromosome 6. The csgl3 gene was mapped between the dCAPs markers dCAPs-21 and dCAPs-19, at genetic distances of 0.05 cM and 0.15 cM, respectively. The physical distance of this region was 19.6 kb. Three markers, InDel-19, dCAPs-2 and dCAPs-11, co-segregated with csgl3. There were two candidate genes in the region, Csa6M514860 and Csa6M514870. Quantitative real-time PCR showed that the expression of Csa6M514870 was higher in the tissues of 9930 than that of NCG157, and this was consistent with their phenotypic characters. Csa6M514870 is therefore postulated to be the candidate gene for the development of trichomes in cucumber. This study will facilitate marker-assisted selection (MAS) of the smooth plant trait in cucumber breeding and provide for future cloning of csgl3. 相似文献
10.
Parameters of brown-headed cowbird Molothrus ater egg discrimination in warbling vireos Vireo gilvus
We examined which egg parameters warbling vireos Vireo gilvus use to discriminate brown-headed cowbird Molothrus ater eggs and, by comparing our results to other studies, tested the prediction that ejecter species with eggs more similar in appearance to cowbird eggs will be less tolerant of foreign eggs. In addition, we tested the hypothesis that egg characteristics influence the cost of ejection and probability of committing ejection errors. Warbling vireos ejected 100% of eggs with a cowbird spot pattern and only spot pattern significantly influenced the probability of ejecting a foreign egg, whereas size and nest stage did not. Foreign eggs that differed in two parameters were not ejected significantly more than those that differed in one parameter. Thus, warbling vireos appear to be less tolerant of foreign eggs than species with eggs more divergent from cowbird eggs. There was no significant difference in the number of vireo eggs that were damaged when foreign eggs of different sizes and spot patterns were ejected, which is counter to the assumptions of the evolutionary equilibrium hypothesis. Similarly, foreign egg characteristics did not significantly influence the probability of ejection errors. Finally, egg discrimination in warbling vireos appears to have evolved directly to counter cowbird parasitism because all conspecific eggs switched into their nests were accepted. 相似文献