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1.
Wissler receives scant notice today although he was a major figure in American anthropology. During the decades when the historical particularism of Franz Boas dominated American cultural anthropology, Wissler's theories provided a nomothetic alternative. His theories are in current use in various guises. The importance of Wissler has been obscured to some extent because he is often misclassified as a Boasian. However, he consciously worked outside of Boas's influence.  相似文献   

2.
A new subgenus of Polia, Metallopolia subgen. n., two new species (Polia (Metallopolia) dysgnorima sp. n. and P. (M.) metagnorima sp. n.) from China (Sichuan, Yunnan, Gansu), and a new subspecies, P. (M.) subviolacea kanchenjunga ssp. n. from Nepal and SE Tibet (Sikkim) are described. Habitus, antennae, male and female genitalia of all Metallopolia species are characterised, depicted and compared with the related species.  相似文献   

3.
ABSTRACT

To some, zoos are prisons exploiting animals. In reality zoos range from bad to better. I make this distinction: A bad zoo makes animals work for it; a good zoo works for animals. Good zoos do effective conservation work and continually strive to improve exhibits, relevance to conservation, and inspiring public engagement for wildlife. Many zoos have improved enormously; the better ones being crucial in saving species that would have otherwise gone extinct. Nonetheless, for some people the mere word “zoo” carries impressions of old zoos, bad zoos, circuses, and theme-park shows that many find distasteful. Good zoos know they must innovate forward. As society grows increasingly estranged from nature and continues driving broad declines of wildlife, wild lands, and natural systems, the goal of zoos and every organization concerned with animal welfare should not be to separate humans from other animals, but to entangle all humans in nonhuman lives. Zoos of the next decades must become the first stage in bringing young people into life-long, engaged caring about animals. They could carry on that mission in their communities, in schools, in wild lands, as well as inside their gates. Without a strong public constituency, wild animals will not withstand continued human proliferation. Zoos and aquariums must innovate toward being a crucial force abetting the continued existence of wildness on Earth. Zoos of the future must become uplifting places of respect, rescue, enhancement, conservation, and public engagement.  相似文献   

4.
在全球资源和环境危机下,物种和生态层面的宏观动物学研究已成为可持续发展的重要课题。本文基于英国自然历史博物馆和中国科学院动物进化与系统学重点实验室2009~2013年动物学领域研究进展的可视化对比分析,以揭示两机构近5年宏观动物学研究的现状、热点、差异以及未来发展趋势。分析发现,两机构在动物分类、系统进化与生物多样性等宏观动物学研究方向十分类似;作者聚类方面中国科学院动物进化与系统学重点实验室多侧重于中国昆虫纲研究,而英国自然历史博物馆研究的动物类群更具多样性且地区跨度更广;中国科学院动物进化与系统学重点实验室目前最主要的研究热点乃至未来相当一段时间的研究前沿仍为中国新物种的经典分类学研究;英国自然历史博物馆的研究热点则已转向中国和印度等发展中国家的新物种发现与描记,在经典分类学基础上的物种多样性和系统发育学研究则是英国自然历史博物馆宏观动物学的研究前沿。  相似文献   

5.
A characteristic electric organ discharge display in social encounters between mormyrid fish is a temporary discharge cessation. Using this response, we have investigated the useful range of electrocommunication under different water conductivity conditions in the mormyrid Brienomyrus niger. An individual fish was confined to a porous ceramic shelter tube and moved from a starting distance of 380 cm toward a similarly confined conspecific until discharge, cessation occurred. The moved fish was subsequently returned to its original, position. Water conductivity affects the peak-to-peak source voltage of the electric organ and the sensitivity of the fish's electroreceptors. Within a range of 10 to 36 000 μS/cm, the peak-to-peak amplitude of the electric organ discharge declined as a power function. At 120 μS/cm, the amplitude was 50%, and at 300μS/cm, 30% of the 10 μS/cm value. The interfish distance at which discharge cessation occurred and the associated electric field gradients were dependent on water conductivity and upon the spatial orientation of the two fish (end-to-end or parallel orientations of their shelter tubes). The respective ranges were from 135 cm and 0.02 mV/cm at 52 μS/cm (parallel orientation) to 22 cm and 0.36 mV/cm at 678 μS/cm (end-to-end orientation). When the data for both tube orientations were combined, the relationship between water conductivity (x) and the distance at which discharge cessation occurred (y) could be expressed by a power function, y=K·xa (with K=102.97 and a=?0.56). When an electrically ‘silent’ fish was moved away from its conspecific, a discharge resumption in the form of a high-frequency rebound occasionally effected changes in the other fish's discharge activity at distances up to 157 cm (with an associated electric, field gradient of 0.01 mV/cm under the lowest conductivity condition).  相似文献   

6.
Castrated zebra finches receiving one of six hormone treatments were given three weekly tests with different females and their sexual behavior was contrasted with that of two control groups consisting of intact or castrated males given implants of cholesterol. The six hormone treatments were: two aromatizable androgens, testosterone (T) and androstenedione (AE); two nonaromatizable androgens, androsterone (AN) and dihydrotestosterone (DHT); an estrogen, estradiol (E); or a combination of E + DHT. Half the males receiving DHT received the 5α-isomer, half received the 5β-isomer. Castration significantly reduced the proportion of males which courted females, total courtship displays, high-intensity courtship displays, beak wiping activity, and significantly increased the latencies to show these behaviors compared to intact males. Castrated males never attempted to mount a female. All of these measures of courtship and copulatory behavior were restored to normal levels only by treatments providing both estrogenic and α-androgenic metabolites (i.e., T, AE, E + αDHT). AE was clearly the most effective of these, raising behavior significantly above normal on several measures. AN treatment was more effective than αDHT on all measures and not significantly different from intact birds on some. Treatment with E, αDHT, βDHT, or E + βDHT was totally ineffective. Surprisingly, females only solicited males whose hormone treatments provided estrogenic metabolites. Not only did they solicit males given aromatizable androgens, which showed high rates of courtship activity, they also solicited males given E or E + βDHT, some of which never even courted. Castration and hormone treatment also affected body and syringeal weight, but in opposite directions. Castration increased body weight while decreasing syringeal weight. Hormone treatments providing α-androgenic metabolites decreased body weight and increased syrinx weight. Treatments supplying estrogen as well were slightly more effective.  相似文献   

7.
狶科化石一新种在内蒙古上始新统的发现   总被引:1,自引:1,他引:0  
记述了在我国内蒙古沙拉木仑地区晚始新世乌兰戈楚组中发现的科化石———内蒙古短面 (新种 ) (Brachyhyopsneimongolensissp .nov .)。新种的主要特征是 :下颌骨深 ,前臼齿部分更缩短 ,下缘明显斜向前上方 ,颊齿主尖高锐 ,脊形 ,上臼齿梯形 ,已形成原脊 ,原尖位置靠后 ,M3具次尖 ,后齿带弱。研究表明Eoentelodon和Brachyhyops在下颌骨具骨质突起的刍形 ,前部缩短 ,下颌骨联合达p3,p3与p4彼此紧靠 ,下臼齿的下前尖与下后尖明显分开 ,以及上颊齿的形态上都很接近。Eoentelodon为Brachyhyops的后出同物异名  相似文献   

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