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1.
《Journal of Natural History》2012,46(29-32):1853-1861
The effects of the number of locules per fruit on seed predation in a Mediterranean woody plant (Cistus ladanifer) were analysed. Plants produced fruits with a similar number of locules (fruits with a small, intermediate or large number of locules). Nevertheless, there were no differences in the number of fruits produced or predated per plant. Different types of fruits did not differ in size, seed weight, fruit to wall ratio, insect predation rate or mean proportion of destroyed locules. They did differ, however, in the variation of the proportion of destroyed locules; fruits with few locules had a wider variation than fruits with a large number of locules. Our results suggest that phenotypic selection pressure on insect predation could give rise to more between‐fruit variation in the seed output saved from predation in those plants producing fruits with a small number of locules.  相似文献   

2.
《Journal of Natural History》2012,46(27-28):1663-1687
Most of the studies on the bee fauna of cerrado have shown incomplete approaches, focusing on species diversity or on a fraction of the assemblage. This work presents similarities among bee species based on visited plants and also shows taxonomic diversity of bees for plant resource sets offered by species in a cerrado area (Pé-de-Gigante), one of the few conservation areas of cerrado in the São Paulo State, Brazil. A total of 737 specimens, belonging to 71 bee species, were collected visiting 52 plant species. Species clusters based on visited plants show that species of Epicharis, for example, are more similar among themselves than from species of other genera. In addition, bee assemblage showed a nested structure, indicating the presence of specialist species exploiting resources subsets used by generalist species under strong intra-specific and weak inter-specific competitions.  相似文献   

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4.
《Journal of Natural History》2012,46(35-36):2145-2158
The diversity of Oniscidean isopods was studied in Vendicari, a protected area in southeastern Sicily characterized by salty ponds separated from the sea by narrow bands of land. Samples were collected in pitfall traps placed in transects from the coastline to the ponds and from the ponds inland. Twenty-three species were identified, only seven of which were present at all sampling sites. Shannon's diversity and Pielou's evenness indices revealed higher values in the spring and autumn; activity indices were also calculated for each species for all months of the year. Similarity among sampling sites was evaluated qualitatively with Jaccard's index and quantitatively with Sørensen's index. The ponds seem to play the same role as the seacoasts regarding species zonation.  相似文献   

5.
《Journal of Natural History》2012,46(28):2661-2669
The importance of introduced rats as damaging factors on island biotas is globally recognized. The predation of artificial avian nests by Ship rats (Rattus rattus) in fragmented laurel forests in Tenerife (Canary Islands) was explored. The influence of road edge, patch type, and position (ground versus tree) on nest survival in two forest remnants differing in conservation degree, were assessed using failure‐time analysis. Overall, nest predation was greater in the preserved than in the disturbed remnant. Nest predation also differed among and within patches, variation being greater within the disturbed remnant. The probability of nest failure was higher at the interior than along the road edge in both remnants, but the road edge effect on nest predation was more intense in the disturbed remnant. Predation pressure was higher in patches of mature, closed canopy or dense understorey with stump sprouting. Ground nests were predated at higher rates than tree nests at any location. These results contrast with other nest predation studies in fragmented landscapes where forest edges rather than the interior are more frequently used by predators. Predatory activity by rats seems negatively affected by forest disturbance and road edge effect. Overall, artificial nest predation patterns by rats confirm a potential predation risk for the avifauna of the Canarian laurel forest. This should be considered in implementing conservation management programmes.  相似文献   

6.
ABSTRACT

Four new species, Grouvellinus nigerquadratus sp. nov., G. cruxniger sp. nov., G. luciaensis sp. nov., and G. borneensis sp. nov., are described from Borneo and illustrated in detail. Two additional species of the genus which remain undescribed are briefly diagnosed. The material was collected during Taxon Expeditions’ field course which involved citizen scientists, students and taxonomists. Specimens were collected at altitudes between 270 m and 750 m above sea level using fine-meshed hand-nets and blacklight traps. The morphological species delimitation based on morphology was supplemented and congruent with mtDNA sequences which are the first DNA barcodes for the genus from Borneo. They were obtained in the field using a newly developed rapid and accurate MinION-based workflow. The inter – and intraspecific genetic distances and the problems regarding cryptic species delimitation are discussed.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:4B1D0F3D-B303-46A5-86B4-C23454192327  相似文献   

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