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141.
SYNOPSIS. Limnology was not recognized as a distinct scienceat the time of the great post-Civil War western explorationsof Hayden, Wheeler, King, and Powell. However, these and someearlier explorations made observations in certain branches ofnatural science that would become integral parts of limnologicalscience. In keeping with what was known at the time, some exploringparties made observations and collections, such as water temperatureor water samples and larger invertebrates, which could be readilyaccomplished by hand or with simple equipment. The inconvenienceof carrying or expending time to build boats for offshore usemay have seriously deterred limnological work. 相似文献
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PEGGY EBY 《Austral ecology》1998,23(5):443-456
Abstract The Grey-headed flying fox Pteropus poliocephalus Temminck 1825 is the only mammalian frugivore to occupy substantial areas of the subtropical rainforests of eastern Australia. The composition of the P. poliocephalus diet and diet specialization in the species are therefore pertinent to studies of trophic structure, seed dispersal and evolutionary processes in these forests. During a three-year diet study, P. poliocephalus used fruits from 44 species of canopy and edge plants. Their taxonomically diverse diet was dominated by the Myrtaceae and Moraceae. Dietary specialization by P. poliocephalus was examined using two criteria: the influence of fruit morphology on diet choice and dietary overlap with sympatric avian frugivores. There was no evidence from either approach that they were specialist feeders. Initial analyses comparing the morphological characters of diet fruits with fruits available to P. poliocephalus during the study period showed a preference for white fruits, berries, syconia and fruits with multiple seeds, and avoidance of black fruits and drupes. However, these significant results were not sustained when the confounding effects of correlations between fruit morphology and other traits were considered. All, except the response to berries, could be attributed to either avoidance by P. poliocephalus of secondary compounds in the Lauraceae or selection for the beneficial phenology of Ficus. Dietary overlap with frugivorous birds was notably high and the fruit diet of P. poliocephalus formed a subset of the avian diet. Associations between fruit colour, size and protective mechanisms have been documented in other rainforest areas and have been proposed as indicators of coadaptive relationships between vertebrate frugivores and their diet plants. However, these associations were not apparent in the morphological characters of fleshy fruits from Australian subtropical rainforest trees. An explanatory hypothesis of primarily avian influence on fruit traits is presented. 相似文献
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The control of the swarming of Proteus vulgaris by boric acid 总被引:2,自引:0,他引:2
146.
PEGGY MOTSCH JEAN‐PAUL GONZALEZ DELPHINE VERRIER 《American journal of primatology》2012,74(3):236-246
Clinical blood biochemistry and hematology are valuable tools to evaluate health and welfare in many animal species. In order to document the general biology of one of the most poorly known nonhuman primate species, and contribute to its conservation, the clinical blood biochemistry and hematology of the sun‐tailed monkey (Cercopithecus solatus Harrisson) was investigated in its range of endemicity in Gabon. Data derived from 26 years of clinical monitoring of the only semicaptive colony of this species in the world, housed at CIRMF (Franceville, Gabon), were analyzed in order to establish reference values of age–sex classes. Consistent with previous reports in other primate species, age and sex significantly affected a number of biochemical and hematological parameters in C. solatus. Hematological analyses demonstrated significant differences in red blood cells, hemoglobin (HB), and hematocrit (HT), with males showing significantly greater values than females. In contrast, neutrophil counts were greater in females. An ontogenetic effect was detected for HB, HT, eosinophil, and monocyte counts, while lymphocytes significantly decreased with age. Biochemical analyses also showed significant differences, with females displaying greater cholesterol and alanine aminotransferase levels. Increase in levels of blood urea and aspartate aminotransferase coupled with decrease in albumin in old individuals suggested declining kidney, liver, and muscle functions with age. Interspecific comparisons were conducted and the effects of the unique semifree‐ranging setting on the validity and value of the results presented are discussed. The reference values established will be useful in further ecological, parasitological, and virological studies of the sun‐tailed monkey. 相似文献