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41.
S.M. Walker P.A. Prodöhl E.M. Hoey I. Fairweather R.E.B. Hanna G. Brennan A. Trudgett 《International journal for parasitology》2012,42(13-14):1193-1199
The liver flukes, Fasciola hepatica and Fasciola gigantica, are considered to be sister species and between them present a major threat worldwide to livestock production. In this study sequence data have been employed from informative regions of the nuclear and mitochondrial genomes of over 200 morphologically F. hepatica-like or F. gigantica-like flukes from Europe, sub-Saharan Africa and South Asia to assess genetic diversity. Evidence is presented for the existence of four well-separated clades: African gigantica-like flukes, Indian gigantica-like flukes, European hepatica-like flukes and African high-altitude hepatica-like flukes. Application of the Biological Species Concept to trematodes is problematic; however, the degree of separation between these groups was sufficient for them to be considered as distinct species using the four times rule for speciation. 相似文献
42.
Bellwood DR Baird AH Depczynski M González-Cabello A Hoey AS Lefèvre CD Tanner JK 《Oecologia》2012,170(2):567-573
The dynamic nature of coral reefs offers a rare opportunity to examine the response of ecosystems to disruption due to climate change. In 1998, the Great Barrier Reef experienced widespread coral bleaching and mortality. As a result, cryptobenthic fish assemblages underwent a dramatic phase-shift. Thirteen years, and up to 96 fish generations later, the cryptobenthic fish assemblage has not returned to its pre-bleach configuration. This is despite coral abundances returning to, or exceeding, pre-bleach values. The post-bleach fish assemblage exhibits no evidence of recovery. If these short-lived fish species are a model for their longer-lived counterparts, they suggest that (1) the full effects of the 1998 bleaching event on long-lived fish populations have yet to be seen, (2) it may take decades, or more, before recovery or regeneration of these long-lived species will begin, and (3) fish assemblages may not recover to their previous composition despite the return of corals. 相似文献
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JOSÉ ANTONIO FERNÁNDEZ PRIETO CARLOS AGUIAR EDUARDO DIAS MARIA ISABEL GUTIÉRREZ VILLARÍAS 《Botanical journal of the Linnean Society. Linnean Society of London》2008,157(3):493-499
The majority of authors consider Festuca jubata Lowe as an endemic species common to Madeira and the Azores. Saint-Yves proposed that F. jubata was an Azorean endemic and described a geovicarious taxon in Madeira: F. filiformis C. Sm. ex Link in Buch ssp. mandonii St.-Yves. We undertook a complete bibliographical revision of the taxonomy, nomenclature, and chorology of F. jubata s.l. , and contrasted it with morphological and anatomical studies performed on samples from the Azores and Madeira. Azorean plants usually identified as F. jubata had a character combination distinct from that of those with a Madeiran provenance. Saint-Yves' proposal of two independent taxa was correct, but he erroneously considered F. jubata as an Azorean endemic because the name F. jubata was based on Madeiran plants. Consequently, F. jubata auct. pl. from the Azores belongs to a new species. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 493–499. 相似文献
44.
DESCRIPTION OF THE SENSORY CHARACTERISTICS OF SPANISH UNIFLORAL HONEYS BY FREE CHOICE PROFILING 总被引:1,自引:0,他引:1
MIGUEL ANGEL GONZÁLEZ-VIÑAS AIDA MOYA MARIA DOLORES CABEZUDO 《Journal of sensory studies》2003,18(2):103-113
Different Spanish unifloral honeys (eucalyptus, sunflower, rosemary, thyme, lavender, citrus, anise, quercus, and lemon blossom) and one multifloral honey were studied by Free-Choice Profiling (FCP) analysis. Generalized Procrustes Analysis (GPA) applied to the FCP data allowed discrimination between samples and provided information on the attributes responsible for the differences observed. The honeys had significantly different sensory characteristics. Textural attributes were the predominant factor in discriminating between samples, and appearance (color included) was also correlated with GPA dimensions to a lesser extent. 相似文献
45.
Reproductive ecology of Rhododendron ponticum (Ericaceae) in relict Mediterranean populations 总被引:2,自引:0,他引:2
JOSÉ A. MEJÍAS JUAN ARROYO FERNANDO OJEDA† 《Botanical journal of the Linnean Society. Linnean Society of London》2002,140(3):297-311
In the southern Iberian Peninsula, Rhododendron ponticum occurs in restricted and vulnerable populations as a Tertiary relict. Population structure and the main phases of the reproductive process were examined in order to shed light on recruitment patterns and limitations. Rhododendron ponticum flowers are self-compatible and attract a diverse array of insects, which are responsible for a considerable number of seeds set in the populations. Nevertheless, only adults form populations, whilst seedlings are scarce and saplings virtually absent (only two juveniles out of 2489 adults sampled). Non-specialized vegetative multiplication by layering was observed. Recruitment failure seems to depend on the scarcity of safe microsites, which are free from drought, for seedling establishment. The observations contrast with R. ponticum 's reputation as an aggressive invader in temperate Atlantic areas. It is proposed that the species shows a variable balance between sexual reproduction and vegetative multiplication depending on environmental conditions. At present, only the latter seems to be prevailing in relict populations in the Iberian Peninsula. This flexible reproductive strategy is also discussed as a mechanism allowing persistence during geological climatic oscillations. © The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 297–311. 相似文献
46.
Homeobox proteins as sequence-specific transcription factors 总被引:48,自引:0,他引:48
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