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71.
《Journal of Natural History》2012,46(19-20):1169-1179
The homing ability of the rock pool blenny Parablennius parvicornis was studied at a rocky shore on Gran Canaria (Canary Islands, Spain). A total of 140 fish was tagged in five different rock pools and 100 of these were displaced from their original site, during low tide. This blenny species shows great site fidelity and is able to return home from 400 m away. Results show that homing success mainly depends on the displacement distance and it increases when fish return against the current, whereas sex and fish size have no influence. 相似文献
72.
《Journal of Natural History》2012,46(17-20):1227-1235
In this study we analysed the acoustic activity of Hylodes heyeri in areas of Atlantic Forest, in southern Brazil. Observations were made in November 2001 and from January to April 2002, at Estação II Instituto Agronômico do Paraná, municipality of Morretes, State of Paraná. Males displayed three different vocalizations: advertisement calls, territorial calls, and courtship calls. Temporal and spectral parameters of advertisement and territorial calls were analysed, along with call intensity. The duration of the advertisement call showed a negative correlation with air temperature, with males decreasing the duration of advertisement calls at higher temperatures. Male body size was not correlated with any of the acoustic parameters. Details on habitat use, distances to nearest vocalizing neighbour, and daily calling activity are also included. 相似文献
73.
《Journal of Natural History》2012,46(17):1367-1380
The parasitic wasp Trogus pennator (Ichneumonidae) attacks the larvae of swallowtail butterflies (Papilionidae). Female T. pennator were followed in the field as they searched for larvae of the zebra swallowtail butterfly, Eurytides marcellus (Papilionidae), feeding on Asimina (Annonaceae) in central Florida, USA. Predictions of host‐finding theory and interactions with the host were thus investigated in a natural setting. Wasps seldom flew to plants other than Asimina and apparently recognized the plants by visual cues. Plants were attractive regardless of host presence, as the wasps approached plants lacking E. marcellus feeding damage twice as often as they approached damaged plants. However, wasps approached damaged plants at a rate greater than their frequency in the Asimina population, indicating that they can detect host damage before they approach the plants. After approaching within 0.5?m of plants, wasps tended not to land on plants lacking feeding damage. A comparison of the plants they landed on, however, showed no consistent preferences for damaged plants. The weaker trends in the latter data indicate that the presence of feeding damage was not the sole criterion for landing, although it evidently influenced behaviour. After landing, wasps spent more time searching damaged plants than undamaged plants. Butterflies preferred to oviposit on plants shorter than those searched by T. pennator. Possible adaptive consequences of this phenomenon are discussed. 相似文献
74.
《Journal of Natural History》2012,46(19-20):1195-1206
Limnomedusa is a monotypic genus that occurs in association with rocky outcrops and stream beds. Based on observational and mark–recapture fieldwork from 2005 to 2008, we report the breeding biology of Limnomedusa macroglossa in southern Brazil. The reproductive season lasted from late August to early February. Tadpoles were recorded from early September to late February. A clear pattern of emergence/recruitment was observed in juveniles. The occurrence of reproductive activities was clearly related to the longest photoperiods, when the highest temperatures occur. Males called from rocky or concrete substrates, mostly under rocks. Amplexus was axillary and the operational sex ratio was nearly even. Spawn occurred in lentic water bodies but tadpoles also completed their development in slow‐flowing water. Although using similar habitats for reproduction, L. macroglossa reached lower levels of specialization toward terrestriality than did the cycloramphids Cycloramphus and Thoropa. We classify L. macroglossa as a breeding habitat specialist that would be threatened by river damming. 相似文献
75.
76.
Concrete cylinders wrapped with glass fabrics of various constructions were fabricated. Compressive behaviours of cylinders with and without fabric wrapping were investigated. Comparisons of the compressive characters while using different fabrication parameters were made. It was demonstrated that the effect of the fabric reinforcement was obvious. The tensile strength of the filament used in the fabric played an important role as far as the anti-compression behaviour of the reinforced cylinders is concerned. 相似文献
77.
体触行为(touch behaviour)是一种复杂的非言语符号系统,是一种文化符号,人们在交际过程中身体部位是否接触及接触的方式和程度,不仅能表达彼此间相互关系的信息,而且存在着巨大的跨文化差异。 相似文献
78.
陶金平 《江苏大学学报(自然科学版)》1994,(5)
非实质性报酬通过对动机的影响而支配着从业者的行为,是一种十分有效的外激励因素,本文从发放基础的角度,把非实质性报酬分为系统报酬、团体报酬和个人报酬三种,并分别论述了其对从业者主观行为即参与行为、公分贡献行为及非公务贡献行为的影响。 相似文献
79.
冯革群 《西北大学学报(自然科学版)》1995,25(6):711-714
运用劳动地域分工理论和工业地域运动理论,通过分析图们江中下游工业发展现状和潜力,提出本区工业地域结构的开发构想。近期加强部门之间关联性和地域间合理性,远期面向整个东北亚地区,以高新技术和高附加值的加工工业为主,作自东向西的工业地域运动。 相似文献
80.
研究ABS/透门石(TS)短纤维复合体系的流变行为,测定该复合体系的粘度随组分的变化及流动活化能,对挤出物的结构形态给出定性的说明. 相似文献