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11.
CANCHAO YANG ANTON ANTONOV YAN CAI BÅRD G. STOKKE ARNE MOKSNES EIVIN RØSKAFT WEI LIANG 《Ibis》2012,154(1):200-204
We documented brood parasitism by the poorly studied Large Hawk‐Cuckoo on a previously unknown host species, the Chinese Babax. Furthermore, we describe a new egg colour for the Large Hawk‐Cuckoo. The parasitism rate of Chinese Babax nests over 4 years was 6.9% (11 of 159 nests), with significant temporal variation. The Large Hawk‐Cuckoo laid immaculate white eggs that appeared non‐mimetic to the blue Babax eggs, an impression that was confirmed by avian visual modelling. Nevertheless, most Cuckoo eggs were accepted by the host, suggesting that this host–parasite system may be evolutionarily recent. 相似文献
12.
LIV BORGEN ULLA-MAJ HULTGÅRD FLS 《Botanical journal of the Linnean Society. Linnean Society of London》2003,142(4):347-372
Patterns of variation at nine enzyme loci were examined in 528 plants representing diploid and tetraploid populations of Parnassia palustris s. l. in Europe to assess genetic variation patterns and migration history. Half of the plants showed a unique multilocus phenotype and 75% of all phenotypes occurred only in Scandinavia. Diploid populations showed similar levels of genetic diversity as other widespread outbreeding species with animal-mediated pollination and F -statistics indicated excessive heterozygosity and low rates of gene flow among them. In spite of dramatic population histories caused by the ice ages, diploid populations have maintained the same genetic diversity in Scandinavia as in central and southern Europe. Northern populations have apparently been established through the gradual advance of genetically variable populations and patterns of variation at individual loci indicate different migration routes, from the south-south-west and the east-north-east, respectively. The data strongly support a repeated autoploid origin of the tetraploid cytotype which has been much more successful than the diploid progenitors in colonizing new land since the last ice age. High genetic diversity in Scandinavia has apparently been obtained by a combination of immigration of plants from different source areas and recurrent formation of autotetraploids from diploid progenitors. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 347−372. 相似文献
13.
GEORGIA E. GARRARD SARAH A. BEKESSY MICHAEL A. McCARTHY BRENDAN A. WINTLE 《Austral ecology》2008,33(8):986-998
There is now a substantial body of literature documenting the detectability of plants and animals under standard survey conditions. Despite the evidence that many flora and fauna species have detection probabilities of less than one, it is still the default assumption of most environmental impact assessment processes that if a species is present, it will be detected. Here we briefly review a number of existing studies that have estimated the survey effort necessary to detect animal species, based on what is known about their detection rates in standard surveys. We then propose a novel method, based on failure‐time analysis, for quantifying the detectability of and determining appropriate survey effort for plant species during flora surveys. We provide computer code for implementing the method in the Bayesian freeware WinBUGS. Methods for estimating detectability can be used to inform minimum survey requirements and have important applications in environmental impact assessment and monitoring. 相似文献
14.
Abstract There is increasing realization that human perceptions of a ‘patchy’ environment do not necessarily relate to that of a particular organism and ecological characteristics of land adjacent to patches of natural vegetation (‘remnants’) may influence the ecological processes within. We investigated how the distribution and abundance of resources within and surrounding 39 small remnants located within the city of Melbourne, Australia, influenced the abundance of common brushtail possums Trichosurus vulpecula (Phalangeridae) and common ringtail possums Pseudocheirus peregrinus (Pseudocheiridae), two primarily folivorous marsupials. Bayesian modelling techniques were used to relate the abundance of both possum species to estimates of den and food availability both within the remnant and within a 100‐m buffer strip extending out into adjacent residential development. We found that both brushtail and ringtail possum abundance within remnants increased with the density of potential den sites within the remnant and food availability within the surrounding landscape. Ringtail possum density within the remnant further increased with den availability within the surrounding landscape. Our results lend support to the hypothesis that, in highly modified landscapes, processes originating outside a remnant vegetation patch may influence the abundance of species within. 相似文献
15.
Genetic evidence from Indian red jungle fowl corroborates multiple domestication of modern day chicken 总被引:1,自引:0,他引:1
Sriramana Kanginakudru Muralidhar Metta RD Jakati J Nagaraju 《BMC evolutionary biology》2008,8(1):174
Background
Domestication of chicken is believed to have occurred in Southeast Asia, especially in Indus valley. However, non-inclusion of Indian red jungle fowl (RJF), Gallus gallus murghi in previous studies has left a big gap in understanding the relationship of this major group of birds. In the present study, we addressed this issue by analyzing 76 Indian birds that included 56 G. g. murghi (RJF), 16 G. g. domesticus (domestic chicken) and 4 G. sonneratii (Grey JF) using both microsatellite markers and mitochondrial D-loop sequences. We also compared the D-loop sequences of Indian birds with those of 779 birds obtained from GenBank. 相似文献16.
MAJBRITT OVERGÅRD SCHOU CASPER RISHOLT TORBEN L. LAURIDSEN MARTIN SØNDERGAARD PETER GRØNKJÆR LENE JACOBSEN SØREN BERG CHRISTIAN SKOV SANDRA BRUCET ERIK JEPPESEN 《Freshwater Biology》2009,54(7):1520-1531
1. Return of large‐bodied zooplankton populations is of key importance for creating a shift from a turbid to a clear‐water state in shallow lakes after a nutrient loading reduction. In temperate lakes, recovery is promoted by submerged macrophytes which function as a daytime refuge for large zooplankton. However, recovery of macrophytes is often delayed and use of artificial plant beds (APB) has been suggested as a tool to enhance zooplankton refuges, thereby reinforcing the shift to a clear‐water state and, eventually, colonisation of natural plants. 2. To further evaluate the potential of APB in lake restoration, we followed the day–night habitat choices of zooplankton throughout summer in a clear and a turbid lake. Observations were made in the pelagic and littoral zones and in APB in the littoral representing three different plant densities (coverage 0%, 40% and 80%). 3. In the clear lake, the zooplankton (primarily Daphnia) were mainly found in the pelagic area in spring, but from mid‐May they were particularly abundant in the APB and almost exclusively so in mid‐June and July, where they appeared in extremely high densities during day (up to 2600 ind. L−1). During night Daphnia densities were overall more equally distributed between the five habitats. Ceriodaphnia was proportionally more abundant in the APB during most of the season. Cyclopoids were more abundant in the high APB during day but were equally distributed between the five habitats during night. 4. In the turbid lake, however, no clear aggregation was observed in the APB for either of the pelagic genera (Daphnia and Bosmina). This may reflect a higher refuge effect in the open water due to the higher turbidity, reduced ability to orient to plant beds and a significantly higher fish density (mainly of roach, Rutilus rutilus, and perch, Perca fluviatilis) in the plant beds than in the clear lake. Chydorus was found in much higher proportions among the plants, while cyclopoids, particularly the pelagic Cyclops vicinus, dominated in the pelagic during day and in the pelagic and high density plants during night. 5. Our results suggest that water clarity is decisive for the habitat choice of large‐bodied zooplankton and that introduction of APB as a restoration measure to enhance zooplankton survival is only a useful tool when water clarity increases following loading reduction. Our results indicate that dense APB will be the most efficient. 相似文献
17.
Samuel D Vasikaran SA Paul Chubb Peter R Ebeling Nicole Jenkins Graham RD Jones Mark A Kotowicz Howard A Morris Hans-Gerhard Schneider Markus J Seibel Greg Ward 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):237-242
Bone turnover markers (BTMs) are classified as either formation or resorption markers. Their concentrations in blood or urine of adults are considered to reflect the rate of bone remodelling and may be of use in the management of patients with bone disease. Major inter-method differences exist for BTMs, and harmonisation of methods is currently being pursued at an international level. Based on published data, this article describes age- and sex-specific Australian consensus reference intervals for adults for serum procollagen type I amino-terminal propeptide (s-PINP) and serum β-isomerised carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX). 相似文献
18.
Graham RD Jones Sabrina DA Koetsier 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):243-250
Reference intervals are commonly considered to allow for between-laboratory bias. The RCPAQAP Liquid Serum Chemistry Program has collected data on laboratory measurements as well as reference intervals. This allows assessment of the between-laboratory variation in results, reference intervals and the information transmitted by the combination of these factors. For the majority of common chemistry analytes, the between-laboratory variation in reference intervals is greater than the variation in results. Additionally the reference interval variation is generally not related to bias between the results. Use of common reference intervals, either as an average of the current intervals in use, or the intervals proposed by the AACB Harmonisation Group, improved the variation seen in the information produced by different laboratories. 相似文献
19.
Three wheat samples collected in 1987 in Central Poland and naturally infected withFusarium spp were analyzed for the presence ofFusarium spp andFusarium toxins. Heads were separated into three fractions: kernels with visibleFusarium damage, healthy looking kernels, and chaff + rachis. The samples contained deoxynivalenol (2.0 – 40.0μg/g), nivalenol (O.O1μg/g), 4,7-dideoxynivalenol (0.10 – 0.15μg/g). 15-acetyldeoxynivalenol (0.10–2.00 μg/g), 3-acetyldeoxynivalenol (O/1Oμg/g), and zearalenone (0.01–2.00μg/g). This is the first report about 15 - acetyldeoxynivalenol in European wheat and the co-occurrence of 3 - acetyldeoxynivalenol and 15-acetyldeoxynivalenol in the same sample of contaminated cereals. 相似文献
20.