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RAQUEL VASCONCELOS ANA PERERA PHILIPPE GENIEZ D. JAMES HARRIS SALVADOR CARRANZA 《Zoological Journal of the Linnean Society》2012,164(2):328-360
Recent phylogeographical analyses using mitochondrial DNA (mtDNA) sequences indicate that the Tarentola geckos from the Cape Verde archipelago originated from a propagule that dispersed from the Canary Islands approximately 7.7 Mya and that underwent a fast evolutionary radiation. Molecular analyses carried out to date clearly show some incongruences with the current taxonomy of Tarentola from the Cape Verde Islands, with some species being paraphyletic or polyphyletic, and several independently evolving lineages needing formal taxonomic recognition. The aim of this study was to clarify the systematics of this group to unravel its taxonomy by applying an integrative approach based on information from three independent sources: mtDNA, nuclear genes, and morphology. As a result of this taxonomic revision, two novel species for the islands of S. Nicolau and Fogo are described and eight subspecies are upgraded to species level. Moreover, an identification key for the genus Tarentola from the Cape Verde archipelago is presented. This study reconciles taxonomy and phylogeny in this group, provides a better understanding of diversity patterns, new insights on evolutionary hypotheses, and supports the basic framework for the future management and conservation of this unique reptile radiation. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 328–360. 相似文献
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ABSTRACT Global Positioning System (GPS) collars are increasingly being used to study fine-scale patterns of animal behavior. Previous studies on GPS collars have tried to determine the causes of location error without attempting to investigate whether the accuracy of fixes provides a correspondingly accurate measure of the animal's natural behavior. When comparing 2 types of GPS collar, we found a significant effect of collar weight and fit on the rate of travel of plains zebra (Equus burchelli antiquorum) females in the Makgadikgadi, Botswana. Although both types of collar were well within accepted norms of collar weight, the slightly heavier collars (0.6% of total body mass [TBM]) reduced rate of travel by >50% when foraging compared with the collar that was 0.4% of TBM. Collar effect was activity specific, particularly interfering with grazing behavior; the effect was less noticeable when zebras crossed larger interpatch distances. We highlight that small differences in collar weight or fit can affect specific behaviors, limiting the extrapolation of fine-scaled GPS data. This has important implications for wildlife biologists, who hitherto have assumed that collars within accepted weight limits have little or no effect on animal movement parameters. 相似文献
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LIZ J. TRENCHARD PHIL J. C. HARRIS STEVE J. SMITH NICK M. PASIECZNIK 《Botanical journal of the Linnean Society. Linnean Society of London》2008,156(3):425-438
The genus Prosopis contains 44 species of trees and shrubs, the majority of which originate in the Americas. Most species are reported to be diploid, with a somatic chromosome number of 2 n = 28. There are rare reports of polyploidy, although it is thought that these may represent polysomaty in root tissues. However, flow cytometry has recently indicated that P. juliflora is entirely tetraploid with a somatic chromosome number of 2 n = 56. In order to clarify the situation, an extensive review of ploidy in Prosopis was undertaken, the first of its kind. The ploidy levels of 124 samples of Prosopis from 21 countries, including both the natural and introduced ranges, were analysed using flow cytometry. In addition, a comprehensive literature review was carried out, examining 305 published ploidy values and covering 32 of the 44 species of Prosopis . Flow cytometry analysis suggests that P. juliflora is the only tetraploid species, with a somatic chromosome number of 2 n = 4 x = 56, whilst the remainder of the species analysed are diploid with 2 n = 2 x = 28, including the first report for P. articulata (2 n = 28). A critical review of published ploidy values shows that all species of Prosopis are reported to be entirely diploid, except P. glandulosa , P. juliflora , and P. koelziana , for which both diploid and tetraploid values have been recorded. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 425–438. 相似文献
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Aphides ( Capitophorus fragariae ) were fed for periods of up to 24 hr. on strawberry plants infected with mild crinkle, severe crinkle or yellow-edge and then transferred to plants of the wild strawberry, Fragaria vesca , or of the cultivated strawberry, variety Royal Sovereign. On F. vesca the symptoms produced were chlorotic speckling, distortion and dwarfing of the leaves, varying in intensity', and on Royal Sovereign scattered, inconspicuous, diffuse, chlorotic spots.
The symptoms from all three sources of infection were similar and were indistinguishable from those of mild crinkle of Harris & King. The virus thus selectively transmitted is tentatively concluded to be the mild crinkle virus.
The virus was transmitted after feeding periods of 1 hr. or more and did not generally persist in the vector for more than 3 hr. 相似文献
The symptoms from all three sources of infection were similar and were indistinguishable from those of mild crinkle of Harris & King. The virus thus selectively transmitted is tentatively concluded to be the mild crinkle virus.
The virus was transmitted after feeding periods of 1 hr. or more and did not generally persist in the vector for more than 3 hr. 相似文献
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Localization of ATPase Activity on the Plasmalemma of Scutellar Epithelial Cells of Germinating Barley (Hordeum vulgare L.) 总被引:1,自引:0,他引:1
Chaffey, N. J. and Harris, N. 1985. Localization of ATPase activityon the plasmalemma of scutellar epithelial cells of germinatingbarley (Hordeum vulgare L.).J. exp. Bot 36: 16121619. ATPase activity has been localized at an ultrastructural levelin the absorptive region of the scutella of germinating barley(Hordeum vulgare L.). The enzyme is localized on the plasmalemmaof the epithelial cells. Using the Gomori reaction the depositionof reaction product on the plasmalemma, which is dependent uponthe presence of supplied ATP, was precluded or reduced by theinhibitors orthovanadate, mercuric chloride and DCCD, whilstß-glycerophosphate would not act as an alternativesubstrate. The mitochondria demonstrated phosphatase activitywith both ATP and ß-glycerophosphate as substrate.The results are discussed in relation to the active uptake ofmetabolites by the scutellum during germination and the structuralmodification of the plasmalemma of the epithelial cells to formplasmatubules. Key words: ATPase, Hordeum vulgare L., localization (ultrastructural) 相似文献