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61.
DAVIDE BASSI JUAN C. BRAGA† ELENA ZAKREVSKAYA‡ ELEONORA P. RADIONOVA§ 《Palaeontology》2005,48(5):929-945
Abstract: From 1935 to 1962 Maslov published two monographs and several other papers on the taxonomy of fossil calcareous algae of diverse ages from the large geographical area of the former USSR. Among many other taxa, he described five new genera ( Solenophyllum , Palaeophyllum , Mesolithon , Bicorium and Tomilithon , as a subgenus of Parachaetetes Deninger) which he attributed to the Corallinaceae, and the new genus Karpathia , which he included in the Squamariaceae. Type material of these taxa, except for Mesolithon , is housed in the Geological Institute of the Russian Academy of Sciences, Moscow. Re-examination of the genus types from a modern perspective of coralline algal taxonomy shows that Karpathia is a validly published genus of corallinaceans (subfamily Mastophoroideae) to which several Cenozoic fossil species can be assigned. In contrast, the holotype of P. elegans , the type species of Palaeophyllum , cannot be assigned to any subfamily within the Corallinaceae and its preserved features are inadequate for confidently delimiting a separate genus. Solenophyllum is a valid genus in which Palaeozoic representatives of Corallinales formerly attributed to Parachaetetes Deninger can be included. Tomilithon is considered a younger heterotypic synonym of Solenophyllum . The algal nature of the bioclasts in the type of Bicorium is uncertain. 相似文献
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MARÍA ELENA GARCÍA 《American anthropologist》2006,108(3):569-570
Natives Making Nation: Gender, Indigeneity, and the State in the Andes. Andrew Canessa, ed. Tucson: University of Arizona Press, 2005. 201 pp. 相似文献
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Bonelli's Eagle Aquila fasciata is one of the rarest birds of prey in Europe, where it has suffered a significant decline in recent decades. We present information on the home-ranges and spatial parameters of 18 Bonelli's Eagles radiotracked in 2002–2006 in Catalonia (northeast Spain) and describe the home-range probability kernel, distances moved, breeding area eccentricity, territorial overlap, nearest neighbour distance and breeding site fidelity, and assess the influence of sex, breeding status, season and geographical area on these parameters. Median home-range according to the minimum convex polygon (MCP) and 95% kernel were 50.3 and 36.1 km2 , respectively. The median breeding area eccentricity was 1477 m. There was considerable overlap in the home-range of both sexes within pairs (MCP: 71.4% and 95% kernel: 98.5%), indicating close pair bonding and similar foraging patterns. Overlap in home-ranges of up to 15% between neighbouring individuals also occurred and was positively related to breeding pair density. There was no difference in spatial parameters between sexes or with breeding status, but during the non-breeding season Eagles had larger home-ranges and stayed further from nests. The high consistency across birds suggests a pattern of spatial use that is characteristic of this species. The high level of use of breeding areas and their surroundings (50% kernel) throughout the year makes it important that these areas be protected from human disturbance. Additionally, it is necessary that heavily used areas away from nesting sites, which are used for foraging and roosting, are identified, protected and managed in a sustainable fashion. 相似文献
67.
RICO GAZAL MICHAEL A. WHITE† ROBERT GILLIES‡ ELI RODEMAKER§ ELENA SPARROW¶ LESLIE GORDON 《Global Change Biology》2008,14(7):1568-1580
The urban heat island effect, classically associated with high impervious surface area (ISA), low vegetation fractional cover (Fr), and high land surface temperature (LST), has been linked to changing patterns of vegetation phenology, especially spring growth. In this study, a collaboration with the Global Learning and Observations to Benefit the Environment (GLOBE) program, we investigated the effect of the urban environment on the timing of leaf budburst of native deciduous trees in seven cities: Asia (Tokyo, Japan; Bangkok and Korat, Thailand), Europe (Jyväskylä, Finland; Bishkek, Kyrgyzstan), Africa (Dakar, Senegal), and North America (Fairbanks, Alaska). The cities differed not only in population size but also in climate and vegetation type. Using Landsat satellite imagery from each city, we calculated LST, Fr, and ISA, and classified sites within each study area as rural or urban. The timing of leaf flushing, measured by students using GLOBE budburst protocols, was statistically different within all cities, with absolute differences ranging from 1 to 23 days. We assessed the classic urban phenology paradigm, which proposes higher LST, lower Fr, and earlier budburst in urban areas of temperate cities. Of the four temperate cities, Tokyo followed the classic paradigm, but no other city demonstrated consistent support. Urban budburst was advanced in three of the four temperate cities, but in only one of the three tropical cities. Results suggest that while vegetation phenology is consistently different between urban and rural areas, a uniform paradigm based on the explanatory variables in this study did not emerge. Although not testable here, it is likely that alterations to chilling requirements in temperate climates and humidity in tropical climates may also influence observed budburst differences. 相似文献
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- 1 Martino's vole Dinaromys bogdanovi is the only living member of the Tertiary genus Dinaromys, and probably also the only surviving member of the Pliomys lineage. The range of the genus Dinaromys has historically been small and its rate of evolution has been low.
- 2 Martino's vole shows all three attributes of rarity in accordance with Rabinowitz's ‘seven forms of rarity’ model: (i) its range is estimated at 43 545 km2 but the area of occupancy is <5200 km2; (ii) its habitat requirements are narrow and the species is strictly tied to exposed, karstified bedrock; and (iii) current populations are invariably small and frequently isolated.
- 3 The Pleistocene range of Martino's vole exceeded the recent one, at least in the north‐western part of the Balkans, and its shrinkage continued into the Holocene.
- 4 Martino's vole may be in competition with the European snow vole Chionomys nivalis, which has a very similar morphology and presumably identical habitat requirements, but is shifted towards an r‐selected life‐history strategy. Long‐term sympatry of these voles has probably resulted in competitive exclusion of the relatively K‐selected Martino's vole by the relatively r‐selected European snow vole.
- 5 Martino's vole consists of two deeply divergent (about one million years ago) phylogeographical lineages, which may represent distinct cryptic species. Rarity is particularly pronounced in the north‐western lineage to the west of the Neretva River, where rocky habitats are largely occupied by the European snow vole.
- 6 In the IUCN Red List of Threatened Animals, Martino's vole is classified as ‘near threatened’. However, the north‐western lineage, which is phylogeographically most divergent and has the greatest genetic diversity, is classed as a ‘vulnerable’ evolutionary significant unit on the basis of its small area of occupancy (<2000 km2). Long‐term population monitoring is an essential step in evaluating the conservation needs of Martino's vole.
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JUDITH MORALES JUAN MORENO SANTIAGO MERINO JUAN J. SANZ GUSTAVO TOMÁS ELENA ARRIERO ELISA LOBATO & JOSUÉ MARTÍNEZ-DE LA PUENTE 《Ibis》2007,149(2):245-254
Female ornamentation has received little attention in studies of sexual selection. Traditionally, female ornaments have been explained as a genetically correlated response to selection in males. However, recent findings suggest that female ornaments may be adaptive. Southern populations of Pied Flycatchers Ficedula hypoleuca are suited for studies of female ornamentation because, in addition to the white wing patch, some females also express the white forehead patch characteristic of males. We thus addressed the associations of these two ornaments with female age and with some health and breeding parameters in a Spanish population of Pied Flycatchers. Female ornament expression was not associated with haemoparasite prevalences, clutch size or parental provisioning effort. However, females expressing the white forehead patch raised more fledglings, and females with larger wing patches bred earlier, had higher number of hatchlings and showed increased levels of total serum immunoglobulins. Thus, these two unrelated epigamic ornaments may indicate some aspects of female quality. Further experimental studies could test the possibility that these plumage traits might function as signals to the males or might be used during female–female aggressive encounters in competition for nest-sites and mates. 相似文献