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81.
We studied the factors that enhance food recognition and consumption in young canaries when confronted with adults. In contrast
to previous studies on canaries, in which social transmission of food habits was studied in the context of dyadic interactions
(one juvenile–one adult), we proposed a more realistic framework in which young canaries were studied in the context of triadic
interactions, free or not, with adults of both sexes. We found that during free interactions, the young bird only eats with
a familiar male and that this association enhances the social transmission of seed handling. When the juvenile was separated
from the adults by a transparent partition, it only learned to husk seed if it was present at the feeder at the same time
as a familiar adult acting as a demonstrator. The presence of adults that are familiar but do not act as demonstrators does
not facilitate social transmission of handling. However, the presence of a familiar, demonstrating female had also no effect
on this transmission. Coordination of the actions of the experienced bird and of the naive subject is required for social
transmission to occur. Action coordination does not depend solely on the level of familiarity between partners but also on
the role played by the demonstrator (here, the adult male) that looks after the juvenile during its transition towards independence. 相似文献
82.
Sandra Steiger Klaus Peschke Josef K. Müller 《Behavioral ecology and sociobiology》2008,62(7):1053-1060
Nestmate recognition in eusocial insects has received a lot of attention in the last decades. Recognition in subsocial species,
in contrast, has been ignored almost completely and consequently, and little is known about proximate mechanisms of recognition
in subsocial systems. We studied one subsocial species, the biparental brood caring burying beetle Nicrophorus vespilloides, an interesting model organism for studies of recognition because of its ability to discriminate between breeding partners
and conspecific competitors. Recognition appears to be based on a chemical cue closely linked to the breeding status of individuals.
Breeding and non-breeding beetles consistently differ in their relative proportions of polyunsaturated cuticular hydrocarbons.
To investigate the function of these polyenes in the burying beetles’ recognition system, we quantified their concentration
on the cuticle during the early state of a breeding attempt and tested the response of breeding beetles in corresponding behavioural
experiments. We observed a rapid increase in the proportion of polyunsaturated hydrocarbons of both males and females after
they were provided with a carcass suitable for reproduction. Furthermore, we found that the relative amount of polyenes on
an individual’s surface was closely correlated with its chance of being accepted as breeding partner. Our results support
the idea that polyunsaturated hydrocarbons are involved in breeding partner recognition in N. vespilloides, functioning as a signal that conveys information about the individual’s breeding status. Breeding females have greater amount
of polyenes than breeding males, and females ingest more carrion during the first days on the carcass, which supports our
hypothesis that precursors for the respective polyenes are derived from ingested carrion. 相似文献
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城市轨道线网规划对优化城市社会、经济、生态环境,实现城市生态环境可持续发展有着至关重要的作用。文章通过熵值法与属性识别模型相结合,建立了基于熵权的属性识别模型,用该方法对城市轨道线网方案进行综合评价,并结合西安市城市轨道交通线网规划中的4个预选方案进行了评价,推选出最优方案。结果表明,该评价方法结果合理,决策科学,具有较好的应用前景。 相似文献
87.
王丹 《辽宁城乡环境科技》2009,(10):26-28
提出一种利用高分辨率遥感影像半自动提取建筑物边缘的方法。先对遥感影像进行预处理,对所有边缘进行边缘检测。然后进行边缘跟踪,提取建筑物的主方向线,利用模型进行线段关系判断,再进行线段关系处理、区域分割和区域生长,最后进行区域合并提取出建筑物的轮廓。用上述方法对Quick Bird卫星的高分辨率影像进行了实验,实验结果证明该方法有较高的识别率、较好的准确性,具有一定的实用价值。 相似文献
88.
海湾型城市定位对湛江城市发展的影响分析 总被引:1,自引:0,他引:1
论文通过空间分析,指出了湛江(城市范围)所具有的典型海湾特性及其基本的空间结构特征,认为湛江城市发展与湛江湾的存在密不可分,而湛江湾的存在又与湛江群岛的关系极为密切,湛江海湾城市最大的特点就是先有岛,再有湾,后有港和城,把湛江定位为海湾型城市符合湛江城市发展的自然本底性质。文章重点就此定位对湛江城市发展可能造成的影响进行了分析,认为,海湾型城市定位可以提高湛江海湾资源的禀赋,有效促进湛江城市的一体化统筹发展。同时,有助于在湛江工业大发展时期到来之际,加强海湾生态环境的保护。最后就如何建设湛江海湾城市提出了一点框架性的思考。 相似文献
89.
Benjamin J. Pitcher Heidi Ahonen Robert G. Harcourt Isabelle Charrier 《Die Naturwissenschaften》2009,96(8):901-909
In pinnipeds, maternal care strategies and colony density may influence a species’ individual recognition system. We examined
the onset of vocal recognition of mothers by Australian sea lion pups (Neophoca cinerea). At 2 months of age, pups responded significantly more to the calls of their own mothers than alien female calls demonstrating
a finely tuned recognition system. However, newborn pups did not respond differentially to the calls of their mother from
alien female calls suggesting that vocal recognition had not yet developed or is not yet expressed. These findings are in
stark contrast to other otariid species where pups learn their mother’s voice before their first separation. Variance in colony
density, pup movements, and natal site fidelity may have reduced selective pressures on call recognition in young sea lions,
or alternatively, another sensory system may be used for recognition in the early stage of life. 相似文献
90.