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A. Louise McIlroy 《BMJ (Clinical research ed.)》1928,1(3506):466-467
55.
The effects of Symbiodinium (Pyrrhophyta) identity on growth,survivorship, and thermal tolerance of newly settled coral recruits
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Shelby E. McIlroy Phillip Gillette Ross Cunning Anke Klueter Tom Capo Andrew C. Baker Mary Alice Coffroth 《Journal of phycology》2016,52(6):1114-1124
For many coral species, the obligate association with phylogenetically diverse algal endosymbiont species is dynamic in time and space. Here, we used controlled laboratory inoculations of newly settled, aposymbiotic corals (Orbicella faveolata) with two cultured species of algal symbiont (Symbiodinium microadriaticum and S. minutum) to examine the role of symbiont identity on growth, survivorship, and thermal tolerance of the coral holobiont. We evaluated these data in the context of Symbiodinium photophysiology for 9 months post‐settlement and also during a 5‐d period of elevated temperatures Our data show that recruits that were inoculated with S. minutum grew significantly slower than those inoculated with S. microadriaticum (occasionally co‐occurring with S. minutum), but that there was no difference in survivorship of O. faveolata polyps infected with Symbiodinium. However, photophysiological metrics (?Fv/F′m, the efficiency with which available light is used to drive photosynthesis and α, the maximum light utilization coefficient) were higher in those slower growing recruits containing S. minutum. These findings suggest that light use (i.e., photophysiology) and carbon acquisition by the coral host (i.e., host growth) are decoupled, but did not distinguish the source of this difference. Neither Symbiodinium treatment demonstrated a significant negative effect of a 5‐d exposure to temperatures as high as 32°C under low light conditions similar to those measured at settlement habitats. 相似文献
56.
Ornob Alam Rafal M Gutaker Cheng-Chieh Wu Karen A Hicks Kyle Bocinsky Cristina Cobo Castillo Stephen Acabado Dorian Fuller Jade A dAlpoim Guedes Yue-Ie Hsing Michael D Purugganan 《Molecular biology and evolution》2021,38(11):4832
The dispersal of rice (Oryza sativa) following domestication influenced massive social and cultural changes across South, East, and Southeast (SE) Asia. The history of dispersal across islands of SE Asia, and the role of Taiwan and the Austronesian expansion in this process remain largely unresolved. Here, we reconstructed the routes of dispersal of O. sativa ssp. japonica rice to Taiwan and the northern Philippines using whole-genome resequencing of indigenous rice landraces coupled with archaeological and paleoclimate data. Our results indicate that japonica rice found in the northern Philippines diverged from Indonesian landraces as early as 3,500 years before present (BP). In contrast, rice cultivated by the indigenous peoples of the Taiwanese mountains has complex origins. It comprises two distinct populations, each best explained as a result of admixture between temperate japonica that presumably came from northeast Asia, and tropical japonica from the northern Philippines and mainland SE Asia, respectively. We find that the temperate japonica component of these indigenous Taiwan populations diverged from northeast Asia subpopulations at about 2,600 BP, whereas gene flow from the northern Philippines had begun before ∼1,300 BP. This coincides with a period of intensified trade established across the South China Sea. Finally, we find evidence for positive selection acting on distinct genomic regions in different rice subpopulations, indicating local adaptation associated with the spread of japonica rice. 相似文献
57.
N. N. Duprey S. E. McIlroy T. P. T. Ng P. D. Thompson T. Kim J. C. Y. Wong C. W. M. Wong S. M. Husa S. M. H. Li G. A. Williams D. M. Baker 《Biodiversity and Conservation》2017,26(11):2521-2545
Economic development and environmental conservation are often seen as opposing forces in the arena of government policy-making. With more than 7 million people and a rich diversity of marine species and habitats, Hong Kong is an excellent case study to explore this dynamic. Despite anthropogenic impacts, Hong Kong still hosts more than 90 species of stony corals within a marine area of 1650 km2. This is remarkable in light of the global plight of coral reefs, which have been reduced by ~80% worldwide in recent decades. The Hong Kong Special Administrative Region has not been immune to this negative trend with an unfortunate track of marine environmental disasters and, as such, can be viewed a harbinger for the future trajectory of coral reefs worldwide. Yet, the story is not entirely negative. Hong Kong possesses key assets, including capable government environmental agencies and competitive research led by local universities, which can bring novel and promising approaches for coral biodiversity conservation in an urbanized context. To coordinate and assist conservation efforts in Hong Kong, we here identify and prioritize major management efforts and identify knowledge gaps for coral conservation based on updated coral biodiversity distribution and a current literature review. Specifically, we propose five priorities for the most positive impact on conservation efforts: (1) reconstruct environmental baselines and establish long-term monitoring of local coral communities, (2) enhance the management and protection of local coral habitats, (3) improve water quality, (4) gain an understanding of the genetic connectivity among local and distant coral communities, and finally, (5) establish an active restoration program for local coral species/communities. In order to build progressive and integrative management strategies for coral biodiversity conservation in Hong Kong, we suggest specific ways in which these priorities be addressed and encourage a fresh dialogue between the government, the public and academia. 相似文献
58.
Blubber cortisol qualitatively reflects circulating cortisol concentrations in bottlenose dolphins
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Cory D. Champagne Nicholas M. Kellar Daniel E. Crocker Samuel K. Wasser Rebecca K. Booth Marisa L. Trego Dorian S. Houser 《Marine Mammal Science》2017,33(1):134-153
Stress hormones, released into circulation as a consequence of disturbance, are classically assayed from blood samples but may also be detected in a variety of matrices. Blubber and fecal samples can be remotely collected from free‐ranging cetaceans without the confounding hormone elevations associated with chase, capture, and handling required to collect blood samples. The relationship between cortisol concentrations in circulation with that of blubber and feces, however, is unknown. To assess these associations, we elevated cortisol by orally administering hydrocortisone for five days in five bottlenose dolphins. Voluntary blood and fecal samples were collected daily; blubber biopsies were collected on day one, just prior to hydrocortisone administration, and days three and five of hydrocortisone administration. We evaluated subsequent changes in several circulating stress hormones as well as cortisol and glucocorticoid metabolites in blubber and feces, respectively. There was a significant association between cortisol levels in serum and in blubber (F1,12.7 = 14.3, P < 0.01, mR2 = 0.57) despite substantial variability in blubber cortisol levels. Counterintuitively, fecal cortisol metabolite levels were inversely related to serum cortisol. The relationship between serum and blubber cortisol levels suggests blubber samples from remote sampling may be useful to detect stress loads in this species. 相似文献
59.
Cladistic and phenetic analyses of leaf and other morphological characters ofGunnera strongly support monophyly of the genus, with the Saxifragaceae s.str. as the closest sister group. This morphologically
based phylogeny provides a more coherent understanding of the evolutionary history ofGunnera than do recent phylogenetic hypotheses based on genetic data sets with Myrothamnaceae as the sister group. Simple, crenate,
palinactinodromously veined leaves lacking freely ending veinlets and tricolpate, tectate-perforate pollen with a reticulate
exine indicate a shared ancestry. Within the genusGunnera all six traditionally recognized subgenera are monophyletic, as supported by leaf architectural apomorphies. The monotypic
subgenusOstenigunnera is the sister group to the other five subgenera, which can be divided into two principal lineages. One lineage includes the
subgeneraMilligania andMisandra, characterized by a prostate stoloniferous habit with small, low-rank leaves and exclusively unisexual flowers, whereas the
other lineage includes the subgeneraPerpensum, Pseudo Gunnera, andPanke, all of which possess at least some hermaphroditic flowers and larger, high-rank leaves. When the phylogeny of the subgenera
is considered in light of biogeography and the fossil record, a number of cladogenetic events can be explained by continental
vicariance in the Late Cretaceous. The AfricanPerpensum became distinct from the other large-leafed lineage with the separation of the African continent ca. 90 Ma. The two small-leafed
lineages, the subgeneraMilligania andMisandra, split with the separation of New Zealand from Western Gondwana, about 80 Ma.Pseudo-Gunnera became isolated fromPanke prior to this time, whenPanke fossils occur in North America.Gunnera probably arose out of an early herbaceous radiation of tricolpate eudicots having close affinity to the basal Saxifragaceae,
espethe genusChrysosplenium. 相似文献
60.
Floral volatiles controlling ant behaviour 总被引:1,自引:1,他引:0
Pat G. Willmer Clive V. Nuttman Nigel E. Raine Graham N. Stone Jonathan G. Pattrick Kate Henson Philip Stillman Lynn McIlroy Simon G. Potts Jeffe T. Knudsen 《Functional ecology》2009,23(5):888-900
1 . Ants show complex interactions with plants, both facultative and mutualistic, ranging from grazers through seed predators and dispersers to herders of some herbivores and guards against others. But ants are rarely pollinators, and their visits to flowers may be detrimental to plant fitness.
2 . Plants therefore have various strategies to control ant distributions, and restrict them to foliage rather than flowers. These 'filters' may involve physical barriers on or around flowers, or 'decoys and bribes' sited on the foliage (usually extrafloral nectaries - EFNs). Alternatively, volatile organic compounds (VOCs) are used as signals to control ant behaviour, attracting ants to leaves and/or deterring them from functional flowers. Some of the past evidence that flowers repel ants by VOCs has been equivocal and we describe the shortcomings of some experimental approaches, which involve behavioural tests in artificial conditions.
3 . We review our previous study of myrmecophytic acacias, which used in situ experiments to show that volatiles derived from pollen can specifically and transiently deter ants during dehiscence, the effects being stronger in ant-guarded species and more effective on resident ants, both in African and Neotropical species. In these plants, repellence involves at least some volatiles that are known components of ant alarm pheromones, but are not repellent to beneficial bee visitors.
4 . We also present new evidence of ant repellence by VOCs in temperate flowers, which is usually pollen-based and active on common European ants. We use these data to indicate that across a wide range of plants there is an apparent trade-off in ant-controlling filter strategies between the use of defensive floral volatiles and the alternatives of decoying EFNs or physical barriers. 相似文献
2 . Plants therefore have various strategies to control ant distributions, and restrict them to foliage rather than flowers. These 'filters' may involve physical barriers on or around flowers, or 'decoys and bribes' sited on the foliage (usually extrafloral nectaries - EFNs). Alternatively, volatile organic compounds (VOCs) are used as signals to control ant behaviour, attracting ants to leaves and/or deterring them from functional flowers. Some of the past evidence that flowers repel ants by VOCs has been equivocal and we describe the shortcomings of some experimental approaches, which involve behavioural tests in artificial conditions.
3 . We review our previous study of myrmecophytic acacias, which used in situ experiments to show that volatiles derived from pollen can specifically and transiently deter ants during dehiscence, the effects being stronger in ant-guarded species and more effective on resident ants, both in African and Neotropical species. In these plants, repellence involves at least some volatiles that are known components of ant alarm pheromones, but are not repellent to beneficial bee visitors.
4 . We also present new evidence of ant repellence by VOCs in temperate flowers, which is usually pollen-based and active on common European ants. We use these data to indicate that across a wide range of plants there is an apparent trade-off in ant-controlling filter strategies between the use of defensive floral volatiles and the alternatives of decoying EFNs or physical barriers. 相似文献