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151.
152.
CAROLINE A. SINCOCK JOAN WATSON F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1988,97(2):179-187
Details of the bennettitalean stomatal apparatus, trichome bases and other cuticular features as seen in the light and scanning electron microscopes are described and an updated scheme of terminology is presented. 相似文献
153.
JOAN LARCOM 《The Australian journal of anthropology》1982,13(4):330-337
The traditional past of the people of South-West Bay, Malekula, featured a great deal of cultural borrowing. Like most Christians in Vanuatu, their negative attitude to a 'pagan' past has been changed into one of positive interest by the recent national emphasis on kastorn. Their older perception of kastorn as commodity - knowledge, rituals, objects, etc. to be bought, sold or exchanged at will - has been supplemented by the more wide- spread notion of kastom as a stable body of traditions, unshared as well as shared. The validatory potential of kastorn is being realized as people re-evaluate and reinvent their past, exploiting lacunae in customary knowledge by imaginative citation of the written ethnographic word. Contemporary needs are apparently more effectively satisfied by reference to fixed truths rather than to fluid and dynamic representations of culture. 相似文献
154.
The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheless, natural selection is expected to select for signals well-suited for effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Stratton 1991. We first explore the transmission characteristics of this important signaling mo-dality by playing recorded substrate-bome signals through three different substrates (leaf Utter, pine litter, and red clay) and measuring the propagated signal. We found that the substrate-borne signal of S stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates (leaf litter, pine litter, and sand), we explored the relationship between substrate-bome signaling and signaling substrate for mating success. We found that muted males were unsuccessful in obtaining copulations re-gardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confirm the importance of sub-strate-borne signaling in & stridulans and suggest a match between signal properties and signal efficacy - leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter. 相似文献
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Abstract. Among samples collected from nineteen localities in Papua New Guinea, we have identified six species within the Anopheles punctulatus complex of mosquitoes, by means of cellulose acetate allozyme electrophoresis. An.punctulatus Dönitz sensu stricto was collected from seven villages in the Madang area and from Buksak, Sausi Mission and an area 18 km SW of Tari; An.koliensis Owen from eight villages in the Madang area, from Popondetta and Brown River near Karema; and An.farauti No. 1 from ten coastal areas including Madang, Lorengau, Popondetta, Port Moresby, Rabaul and Wewak. Three newly recognized species, reported here for the first time, are designated as An.farauti No. 4 from Gonoa and Hudini, Madang area; An.farauti No. 5 from Ketarabo near Goroka; and An.farauti No. 6 from Hiwanda near Tari. Three other known members of the complex, An.clowi Rozeboom & Knight, An.farauti No. 2 (Bryan, 1973) and An.farauti No. 3 (Mahon & Meithke, 1982) were not detected in Papua New Guinea. Problems arising with morphological characters for the identification of species in this group are discussed. 相似文献
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THOMAS FROST LINDA GRAHAM JOAN ELIAS MARK HAASE DONALD KRETCHMER & JAMES KRANZFELDER 《Freshwater Biology》1997,38(2):395-399
1. A previously undescribed symbiotic relationship is reported between the freshwater sponge Corvomeyenia everetti , which occurs throughout eastern North America, and a yellow-green alga.
2. Ultrastructural and pigment analyses place the algal endosymbiont within the class Eustigmatophyceae in the division Heterokontophyta.
3. The relationship of the alga with C. everetti appears to be specific and it contributes significantly to the energy budget of the host.
4. Although the growth form of C. everetti is very similar to other freshwater sponges that usually have green-algal symbionts, its phylogeny has been proposed to be quite distinct, suggesting convergent evolution by both algae and sponges in the development of symbiotic associations in fresh water. 相似文献
2. Ultrastructural and pigment analyses place the algal endosymbiont within the class Eustigmatophyceae in the division Heterokontophyta.
3. The relationship of the alga with C. everetti appears to be specific and it contributes significantly to the energy budget of the host.
4. Although the growth form of C. everetti is very similar to other freshwater sponges that usually have green-algal symbionts, its phylogeny has been proposed to be quite distinct, suggesting convergent evolution by both algae and sponges in the development of symbiotic associations in fresh water. 相似文献