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131.
生态意识及其主要特点 总被引:7,自引:0,他引:7
一、生态意识产生的时代背景生态意识作为人类思想的先进观念,产生于20世纪后半叶。产业革命以来二百多年,人类依据先进科学技术武装的强大生产力,无限制地向自然进 相似文献
132.
Yu. V. Nesterov D. L. Teplyi 《Journal of Evolutionary Biochemistry and Physiology》2004,40(4):438-442
Analysis of parameters of metabolic function of lungs with respect to lipid metabolism was performed in rats under conditions of acute experimental emotional-nociceptive stress. Study of the stress-sensitivity of lungs in the comparative-age aspect has shown different extent of changes of several parameters of lipid metabolism in pulmonary tissue in animals of different age. The results of the study demonstrate areactivity and high stress-stability of lungs with respect to surface-active properties, free-radical processes, and lipase activity in early postnatal ontogenesis. 相似文献
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Jill S. Marty James P. Higham Elizabeth L. Gadsby Caroline Ross 《International journal of primatology》2009,30(6):807-823
Sexual selection has driven the evolution and elaboration of a wide variety of displays and ornaments in male nonhuman primates,
including capes, cheek flanges, and sexual coloration. Among the most sexually dimorphic of all primates is the drill (Mandrillus leucophaeus), the males of which can be 3 times the mass of females, possess large canines, and exhibit extremely bright sexual skin
coloration. However, the function of male coloration in this species has never been examined. Here, we present data on male
color (measured objectively using digital photography), dominance rank, measures of male-female association, and key sexual
behaviors, of adult male drills (n = 17) living in four semi free-ranging enclosures at the Drill Rehabilitation and Breeding Center in Nigeria. We test the
hypothesis that male coloration is a badge of status, indicating dominance rank, and the hypothesis that male coloration attracts
females. We found that male coloration did indicate rank, and that high ranking, strongly colored males were more likely to
associate with adult females, and more specifically with fully tumescent females. These males also engaged in more sexual
activity. However, measures of male-female association and sexual behaviors were not related to male color once rank had been
taken into consideration; i.e., for males of a given rank, females did not prefer those that were more colorful. We discuss
the results in light of what is known about the wild drill social system, in which unfamiliar individuals may come together
in “supergroups,” and in which quality indicators of competitive ability may be particularly important. 相似文献
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Ye. P. Dulepova V. A. Nadtochii L. L. Budnikova 《Russian Journal of Marine Biology》2008,34(7):472-481
The trophic structure of benthic communities in the Sea of Okhotsk and Bering Sea was analyzed based on the results of macrobenthic
survey catches conducted in the Far Eastern seas in the 2000s. The production of trophic levels and entire communities was
determined. It was shown that production of benthic communities is still at a high level and has almost not changed since
the 1980s. The arrangement of the communities of some shelf areas by productivity characteristics was made. 相似文献
140.