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21.
Corey T. Callaghan Richard E. Major William K. Cornwell Alistair G. B. Poore John H. Wilshire Mitchell B. Lyons 《Ecography》2020,43(4):528-538
Understanding species-specific relationships with their environment is essential for ecology, biogeography and conservation biology. Moreover, understanding how these relationships change with spatial scale is critical to mitigating potential threats to biodiversity. But methods which measure inter-specific variation in response to environmental parameters that are also generalizable across multiple spatial scales are scarce. We used broad-scale avian citizen science data, over continental Australia, integrated with remotely-sensed products, to produce a measure of urban-tolerance for a given species at a continental-scale. We then compared these urban-tolerances to modelled responses to urbanization at a local-scale, based on systematic sampling within four small cities. For 49 species which had sufficient data for modelling, we found a significant relationship (R2 = 0.51) between continental-scale urbanness and local-scale urbanness. We also found that relatively few citizen science observations (~250) are necessary for reliable estimates of continental-scale species-specific urban scores to predict local-scale response to urbanization. Our approach demonstrates the applicability of broad-scale citizen science data, contrasting both the spatial grain and extent of standard point-count surveys generally only conducted at small spatial scales. Continental-scale responses in Australia are representative of small-scale responses to urbanization among four small cities in Australia, suggesting that our method of producing species-specific urban scores is robust and may be generalized to other locations lacking appropriate data. 相似文献
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Keyne Monro Alistair G. B. Poore 《Evolution; international journal of organic evolution》2009,63(12):3147-3157
Although modular construction is considered the key to adaptive growth or growth‐form plasticity in sessile taxa (e.g., plants, seaweeds and colonial invertebrates), the serial expression of genes in morphogenesis may compromise its evolutionary potential if growth forms emerge as integrated wholes from module iteration. To explore the evolvability of growth form in the red seaweed, Asparagopsis armata, we estimated genetic variances, covariances, and cross‐environment correlations for principal components of growth‐form variation in contrasting light environments. We compared variance–covariance matrices across environments to test environmental effects on heritable variation and examined the potential for evolutionary change in the direction of plastic responses to light. Our results suggest that growth form in Asparagopsis may constitute only a single genetic entity whose plasticity affords only limited evolutionary potential. We argue that morphological integration arising from modular construction may constrain the evolvability of growth form in Asparagopsis, emphasizing the critical distinction between genetic and morphological modularity in this and other modular taxa. 相似文献
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Kathleen Sullivan Eric van Heugten Kimberly Ange‐van Heugten Matthew H. Poore Ellen S. Dierenfeld Barbara Wolfe 《Zoo biology》2010,29(4):457-469
The objectives of the present research were to conduct a survey to investigate the health history and feeding practices of giraffe in captivity in North America and to obtain samples of hay, concentrate, browse, urine, and serum to compare across zoos, possible factors relating to the development of urolithiasis. Forty‐one out of 98 institutions contacted responded, representing 218 giraffe. All responding zoos fed concentrate and alfalfa hay was the primary forage. Sixty‐five percent of zoos fed browse and 43 different species of browse were listed. Six zoos reported a history of urolithiasis, seven reported wasting syndrome, and 10 reported sudden death. The median daily amount (as fed) of concentrate and hay offered were 5.45 kg (range of 2.73–9.55 kg) and 6.82 kg (range of 2.53–12.50 kg), respectively. The concentrate:hay ratio of the offered diet ranged from 0.22 to 3.47 with a median value of 0.79. Forty‐three percent of the institutions offered a ratio greater than 1:1. Samples of concentrate and hay (six zoos), serum (five zoos), and urine (seven zoos) were obtained for chemical analyses. Analyzed nutrient content of the consumed diet, measured by weighing feed and orts for three consecutive days, met recommendations for giraffe, but was excessive for crude protein and P. Concentrate:hay and serum P were positively correlated (r=0.72; P<0.05). High dietary P content and a high level of concentrate relative to hay may be contributing factors to urolith formation and warrant further investigation. Zoo Biol 29:457–469, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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Andersen H Rossio JL Coalter V Poore B Martin MP Carrington M Lifson JD 《Cellular immunology》2004,231(1-2):85-95
Natural killer (NK) cells and NK cell activities in the rhesus macaque have been incompletely characterized. Using a recently developed rhesus NK target cell line with down-regulated MHC-I (B116Lo) as stimulators and FACS-sorted cells as effectors in a 4-h [51Cr]-release assay we showed that the CD3-CD8lo subpopulation is the primary effector population for NK cell-mediated cytolysis. The majority of these cells co-express CD16, CD11b, NKG2D, and NKp46. To evaluate functional activity at the individual cell level, we employed intracellular cytokine staining and a flow cytometric assay for degranulation, based on cell surface CD107a expression. Flow cytometric analysis revealed that a greater proportion of NK cells degranulated than produced cytokines in response to B116Lo stimulation; the frequency of CD107a-expressing cells within the total NK cell population ranging from 5 to 39%. Somewhat surprisingly, we did not find a significant correlation between lysis, measured by [51Cr]-release assay, and the size of the degranulating NK cell population, implying that additional mechanisms may regulate lytic activity. Use of these approaches should facilitate an improved understanding of NK activity in the rhesus macaque. 相似文献
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Richard Z. Poore 《Marine Micropaleontology》1981,6(5-6)
Quantitative analyses of planktonic foraminiferal assemblages from Deep Sea Drilling Project (DSDP) Holes 334 and 410 demonstrate that subpolar and subtropical faunal provinces existed in the North Atlantic during the late Miocene. Climatic oscillations are clearly recorded in Hole 410 by variations in abundance of the Neogloboquadrina subpolar assemblage. These climatic oscillations have a period of about 1 m.y. Higher frequency oscillations with a periodicity of one to several hundred thousand years are evident from about 6.5 to 7.5 m.y. and are probably present throughout the entire late Miocene.A revised age of 7.0 m.y. is proposed for the first occurrence of the calcareous nannofossil Amaurolithus primus (the Amaurolithus datum). 相似文献
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Erik E. Sotka Tina Bell Lauren E. Hughes James K. Lowry Alistair G. B. Poore 《Zoologica scripta》2017,46(1):85-95
Ampithoid amphipods dominate invertebrate assemblages associated with shallow‐water macroalgae and seagrasses worldwide and represent the most species‐rich family of herbivorous amphipod known. To generate the first molecular phylogeny of this family, we sequenced 35 species from 10 genera at two mitochondrial genes [the cytochrome c oxidase subunit I (COI) and the large subunit of 16 s (LSU)] and two nuclear loci [sodium–potassium ATPase (NAK) and elongation factor 1‐alpha (EF1)], for a total of 1453 base pairs. All 10 genera are embedded within an apparently monophyletic Ampithoidae (Amphitholina, Ampithoe, Biancolina, Cymadusa, Exampithoe, Paragrubia, Peramphithoe, Pleonexes, Plumithoe, Pseudoamphithoides and Sunamphitoe). Biancolina was previously placed within its own superfamily in another suborder. Within the family, single‐locus trees were generally poor at resolving relationships among genera. Combined‐locus trees were better at resolving deeper nodes, but complete resolution will require greater taxon sampling of ampithoids and closely related outgroup species, and more molecular characters. Despite these difficulties, our data generally support the monophyly of Ampithoidae, novel evolutionary relationships among genera, several currently accepted genera that will require revisions via alpha taxonomy and the presence of cryptic species. 相似文献
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