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1.
Miwa Suzuki Ken Hirako Shinji Saito Chie Suzuki Takeshi Kashiwabara Hiroshi Koie 《Zoo biology》2008,27(4):331-340
Ground transport can be a stressful operation for dolphins if the long period of restraint causes damage to internal organs, especially to the lung, generated by their own weight. Buoyancy is deprived from dolphins under moist transport, in which dolphins are transported on mattresses. Upgrading mattresses is an effective way to modify the transportation method so as to compensate for the loss of buoyancy. In Indo‐Pacific bottlenose dolphins (Tursiops aduncus), we tried to find mattresses that performed well at distributing the dolphins' weight and preserved their pulmonary function. When using EV‐17 (thickness, 50 mm) put on EE‐20 (thickness, 50 mm), a wider support area, less extreme changes in pressure, and lower maximum pressures were observed compared with other mattress systems tested. On this mattress system, lower breathing rates, lower heart rates, and higher exhaled CO2 concentrations were shown compared with using standard mattresses. These results suggest that the performance of the combination of EV‐17 and EE‐20 is better than that of the standard mattress in terms of the cardiopulmonary function of dolphins. Zoo Biol 27:331–340, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
2.
Isolation and characterization of novel microsatellite markers for Cymodocea serrulata (Cymodoceaceae), a seagrass distributed widely in the Indo‐Pacific region
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Dan M. Arriesgado Hiroyuki Kurokochi Chunlan Lian Yuichi Nakajima Yu Matsuki Satoshi Nagai Motoshige Yasuike Yoji Nakamura Wilfredo H. Uy Miguel D. Fortes Wilfredo L. Campos Kazuo Nadaoka 《Plant Species Biology》2015,30(4):297-299
Cymodocea serrulata is a tropical seagrass species distributed widely in the Indo‐Pacific region. We developed 16 novel microsatellite (simple sequence repeat) markers for C. serrulata using next‐generation sequencing for use in genetic studies. The applicability of these markers was attested by genotyping of 40 individuals collected from a natural population in the Philippines. Of the 16 loci, 15 showed polymorphism. For the 15 polymorphic markers, the number of alleles per locus ranged from two to seven, and the observed and expected heterozygosities ranged from 0.131–1.000 and 0.124–0.788, respectively. These markers are useful tools for elucidating genetic diversity, connectivity, and structure in this foundational coastal species. 相似文献
3.
Volcanic disturbances and ecosystem recovery at sites of neritic carbonate production are rarely documented, neither in the
recent nor past geological record. Herein, we present a Middle Miocene (ca 14.5 Ma) shallow-marine carbonate record from the
Styrian Basin (Austria) that shows recurrent breakdowns of the carbonate producers (i.e., coralline red algae and zooxanthellate
corals) in response to ashfalls from nearby volcanic island sources. These volcanic events are preserved as distinct marl
layers with idiomorphic biotite crystals and volcaniclasts that mantle the former seafloor topography. The pyroclastic sediments
suffocated the carbonate producers in coral reef and seagrass environments. A subsequent turbid, eutrophic phase caused by
the redistribution, suspension, and dissolution of volcaniclastics is characterized by the spreading of suspension-feeding
biota, coralline algae, and the larger benthic foraminifer Planostegina. During this stage, rapidly consolidated pyroclastic deposits acted as hard grounds for attached-living bivalves. The fact
that the facies below and above the studied ashbeds are almost identical suggests that volcaniclastic events had no long-lasting
effects on the structure of the carbonate-producing benthic communities. Although Miocene shallow-water carbonate systems
of the circum-Mediterranean region are well known and situated in one of the geodynamically most active regions worldwide,
this study is the first that exams the impact of volcanic sedimentation events on shallow marine ecosystems. 相似文献
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CECILIA S. CATALDO DARIO G. LAZO MAISA A. TUNIK M. BEATRIZ AGUIRRE‐URRETA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2013,46(1):114-126
Nerineoid shell beds are described for the first time from Lower Cretaceous deposits of southern South America. These come from carbonates near the top of the Agrio Formation in southern Mendoza Province, west‐central Argentina. To envisage the origin of the nerineoid shell beds, a taphonomic study was carried out, which indicated that these represent within‐habitat time‐averaged, primary sedimentological concentrations with a secondary biogenic imprint related to a relatively high local production of nerineoid shells. The associated palaeoenvironments were studied through a facies analysis of the carbonate succession including the shell beds. The carbonates were deposited in a homoclinal ramp system and depict a shallowing upward trend from mid to inner ramp. The individuals lived and accumulated in oolitic shoals within the inner ramp, in a shallow, well‐lit, high‐energy setting above fair‐weather wave base. Substrate was oxygenated and loose. The nerineoids are shown to belong to one species of the genus Eunerinea, and through the functional morphology of the shells they are tentatively interpreted as infaunal or semi‐infaunal. It is suggested that the recorded monospecific nerineoid shell beds indicate that the palaeoenvironmental conditions may have been favourable for the development of abundant populations of these gastropods in the northern part of the Neuquén Basin during a short time interval in the Hauterivian–Barremian boundary. This could have been related to a brief warming episode, but other factors may have also been involved. □Argentina, Early Cretaceous, Gastropods, nerineoids, Neuquén Basin, shell beds, taphonomy. 相似文献
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Trevor B. Haynes Joel A. Schmutz Mark S. Lindberg Kenneth G. Wright Brian D. Uher‐Koch Amanda E. Rosenberger 《Journal of avian biology》2014,45(3):296-304
Interspecific competition is an important process structuring ecological communities, however, it is difficult to observe in nature. We used an occupancy modelling approach to evaluate evidence of competition between yellow‐billed (Gavia adamsii) and Pacific (G. pacifica) loons for nesting lakes on the Arctic Coastal Plain of Alaska. With multiple years of data and survey platforms, we estimated dynamic occupancy states (e.g. rates of colonization or extinction from individual lakes) and controlled for detection differences among aircraft platforms and ground survey crews. Results indicated that yellow‐billed loons were strong competitors and negatively influenced the occupancy of Pacific loons by excluding them from potential breeding lakes. Pacific loon occupancy was conditional on the presence of yellow‐billed loons, with Pacific loons having almost a tenfold decrease in occupancy probability when yellow‐billed loons were present and a threefold decrease in colonization probability when yellow‐billed loons were present in the current or previous year. Yellow‐billed and Pacific loons co‐occurred less than expected by chance except on very large lakes or lakes with convoluted shorelines; variables which may decrease the cost of maintaining a territory in the presence of the other species. These results imply the existence of interspecific competition between yellow‐billed and Pacific loons for nesting lakes; however, habitat characteristics which facilitate visual and spatial separation of territories can reduce competitive interactions and promote species co‐occurrence. 相似文献
8.
Simple strategy for the in vitro conservation of Ipsea malabarica an endemic and endangered orchid of the Western Ghats of Kerala,India 总被引:2,自引:0,他引:2
A simple protocol was developed for plantlet regeneration from seedling leaf segments of pigeonpea cultivar ICPL 93115 through shoot organogenesis. Ten-day-old seedlings aseptically grown on MS medium were used for furnishing leaf segments. Initial incubation for 5 days in dark at 25±2 °C followed by transfer to 10/14-h light / dark cycle (12.1 mol photons m–2 s–1) favoured regeneration. The decisive role of 6-benzyl adenine at different concentrations was established on shoot organogenesis. Murashige and Skoog's (MS) (1962) medium fortified with BA of 5.0 mg l–1 was optimum for shoot regeneration and MS + BA of 1.0 mg l–1 for shoot elongation, while MS + IAA (1.0 mg l–1) + kinetin (0.1 mg l–1) showed good results for rooting. 相似文献
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M. H. Idris A. Arshad S. M. N. Amin S. B. Japar S. K. Daud A. G. Mazlan M. S. Zakaria F. M. Yusoff 《Zeitschrift fur angewandte Ichthyologie》2012,28(4):597-600
Age and growth of Pinna bicolor were examined in the seagrass beds of Merambong shoal (N 1°19′55.62″; E 103°35′57.75″) off the south‐western coast of Johor, Peninsular Malaysia between May 2006 and April 2007. Monthly growth increment data of P. bicolor were analyzed using FiSAT software (FAO‐ICLARM Stock Assessment Tools) to estimate the asymptotic length (L∞) and growth coefficient (K). Average growth rate of P. bicolor was 1.42 (±0.01) cm per month; the estimated asymptotic length (L∞) and growth coefficient (K) were 34.66 cm and 0.88 per year, respectively. In their natural habitat, P. bicolor attain shell heights of approximately 17, 25 and 30 cm at the end of their first, second and third years of growth. The length–weight relationship was estimated as Log W = ?5.397 + 3.111Log L, and in exponential form the equation was W = 0.000004L3.111 (r2 = 0.99, P < 0.01). Habitat temperature and salinity ranged between 27.47 and 29.66°C and 28.66–33.00 ppt with a mean of 29.10 (±0.66) m°C and 30.52 (±1.41) ppt, respectively. 相似文献
11.
Brachydorus swarupi sp. n. is described from soil about roots of arecanut palm in Kerala State, India. It is the second species to be described in Brachydorus De Guiran and Germani 1968 and differs from B. tenuis, the type species, by its greater length (1.52-2.34 mm for B. swarupi vs. 1.03-1.32 mm for B. tenuis); longer and more delicate stylet (26-35 μm for B. swarupi vs. 20-23 μm for B. tenuis); head shape with concave protrusion at oral aperture (simple rounded in B. tenuis); shorter isthmus and larger posterior bulb in B. swarupi; shorter tail (in B. tenuis c = 9.7 [8.6-11.5] in female, c = 42.3 [33-48] in male); larger spicules and gubernaculum (22-39 μm and 9 -1 2 μm, respectively, for B. tenuis); and phasmids near posterior connection of caudalalae and tail (almost central on caudalalae of B. tenuis). The relationship of Brachydorus to Dolichodorus is discussed. 相似文献
12.
Carbonate breccias in the lower-middle Ordovician Maggol Limestone (Taebacksan Basin,South Korea): Implications for regional tectonism 总被引:1,自引:0,他引:1
Summary Carbonate breccias occur sporadically in the Lower-Middle Ordovician Maggol Limestone exposed in the Taebacksan Basin, South Korea. These carbonate breccias have been previously interpreted as intraformational or fault breccias. Thus, little attention has been focused on tectonic and stratigraphic significance of these breccias. This study, however, indicates that the majority of these breccias are solution-collapse breccias, which are causally linked to paleokarstification. Carbonate facies analysis in conjunction with conodont biostratigraphy suggests that an overall regression toward the top of the Maggol Limestone probably culminated in subaerial exposure of platform carbonates during the early Middle Ordovician. Extensive subaerial exposure of platform carbonates resulted in paleokarst-related solution-collapse breccias in the upper maggol Limestone. This subaerial exposure event is manifested as a major paleokarst unconformity elsewhere beneath the Middle Ordovician sequence, most notably North America and North China. Due to its global extent, the early Middle ordovician paleokarst unconformity (‘the Sauk-Tippecanoe sequence boundary’) has been viewed as a product of second-order eustatic sea level drop during the early Middle Ordovician. Although we recognizes a paleokarst breccia zone in the upper Maggol Limestone beneath the Middle Ordovician sequence, the early Middle Ordovician sequence boundary appears to be a conformable transgressive surface or a drowning unconformity, rather than a major paleokarst unconformity. The paleokarst breccia zone in the upper Maggol Limestone is represented by a thinning-upward stack of exposure-capped tidal flat-dominated cycles that are closely associated with multiple occurrences of paleokarst-related solution-collapse breccias. The paleokarst breccia zone in the upper Maggol Limestone was a likely consequence of repeated high-frequency sea level fluctuations of fourth- and fifth-order superimposed on a second-and third-order eustatic fall in sea level that was less than the rate of tectonic subsidence across the platform. It suggests that second- and thirdorder eustatic sea level drop may have been significantly tempered by substantial tectonic subsidence near the end of maggol deposition. The tectonic subsidence in the basin is also evidenced by the occurrence of coeval off-platform lowstand siliciclastic quarzite lenses as well as debris flow carbonate breccias. With the continued tectonic subsidence, subsequent rise in the eustatic cycle caused drowning and deep flooding of carbonate platform, forming a conformable transgressive surface or a drowning unconformity on the top of the paleokarst breccia zone. This tectonic implication contrasts notably with the slowly subsiding carbonate platform model for the Taebacksan Basin as previously intepreted. Here we propose that the Taebacksan Basin evolved from a slowly subsiding carbonate platform to a rapidly subsiding intracontinental rift basin during the early Middle Ordovician. This study also provides a good example that the falling part of the eustatic sea-level cycle may not produce a significant event at all in a rapidly subsiding basin where the rate of eustatic fall always remained lower than the rate of subsidence. 相似文献
13.
This is the report of a new species of catfish, Kryptoglanis shajii nov. gen. and nov. sp., distinguished from all other genera of siluriform fishes by the combination of the following morphological
characters: viz. the absence of dorsal fin; the presence of four pairs of barbels; an upwardly directed mouth, with a distinctly
projecting lower jaw; subcutaneous eyes; anal fin completely confluent with the caudal fin; anal and caudal fins together
carry 70–74 fin rays; and no spines in any of the fins. Kryptoglanis, which has a maximum recorded size of 59.1 mm in standard length, was collected from a well fed by subterranean springs.
The type locality is a well located at the extreme western part of Western Ghats, near Chalakudy in Thrissur district, Kerala
State, India. 相似文献
14.
STEVEN T. KALINOWSKI 《Molecular ecology resources》2006,6(4):974-979
Deviations from Hardy–Weinberg expectations are frequently a sign of genotyping error. hw‐quickcheck is an easy‐to‐use computer program for detecting departures from Hardy–Weinberg equilibrium. hw‐quickcheck uses exact tests for all of its calculations. These tests include a global test for heterozygote excess/deficiency and genotype‐specific tests. 相似文献
15.
Wei‐Ping Zhang Xin Jia Christian Damgaard E. Charles Morris Yan‐Yuan Bai Sha Pan Gen‐Xuan Wang 《Oikos》2013,122(8):1147-1156
The changes in plant–plant interactions along environmental gradients have been a focus of recent ecological research. It has been suggested that both above‐ and below‐ground competition and their interplay vary along gradients, but few studies have investigated this idea, and in most cases, the role of facilitation has not been considered, despite its importance in high stress environments. Here we used two‐layer ‘zone‐of‐influence’ models to simulate the effects of facilitation, size‐asymmetry of competition, abiotic stress, resource availability and the balance of root–shoot growth on shoot and root interactions and their interplay along an environmental gradient. In the absence of facilitation, shoot and total competition became weaker, while root competition and the interplay between shoot and root competition were unchanged under increasing stress when root competition was completely symmetric. In contrast, shoot, root, total interactions and the interplay between shoot and root interactions were all negative, and they increased with increasing stress when root competition was size‐symmetric. When facilitation was included in the models, net effects of shoot, root, total interactions and the interplay of root–shoot interactions were very different from those without facilitation, and many were positive under highly stressful conditions. The type of stress (non‐resource or resource) did not significantly influence the simulation results. Our study provides an alternative interpretation of the interplay between above‐ and below‐ground plant–plant interactions across an environmental gradient. 相似文献
16.
Leonardo Dapporto Matteo Ramazzotti Simone Fattorini Gerard Talavera Roger Vila Roger L. H. Dennis 《Ecography》2013,36(10):1070-1075
When dissimilarity matrices of faunistic and phylogenetic beta‐diversity turnover indices are projected in dendrograms, a high frequency of ties and zero values produces trees whose topology and bootstrap support are affected by the order of areas in the original presence–absence matrix. We tested the magnitude of this bias and developed R functions to obtain consensus trees after shuffling of matrix row order and applied this algorithm to a multiscale bootstrap procedure. Our functions not only solve the bias of row order but, owing to varying support for different bootstrap scales, reveal fundamental characteristics about the structure of species assemblages. 相似文献
17.
The life cycle of a new haploporid digenean, Hapladena gymnocephali sp. nov., infecting the bald glassy perchlet Ambassis gymnocephalus from the Chaliyar and Kadalundi rivers of Kozhikode district, Kerala, India, is elucidated. The new species is described in detail, its systematic position discussed and compared with related species, H. acanthuri Siddiqi & Cable, 1960 and H. spinosa Manter & Pritchard, 1961. Hapladena gymnocephali is distinctly different from the two latter species in the shape and size of body, nature of testis, extent of vitelline field and excretory bladder. Hapladena gymnocephali has a typical haploporid, two-host life cycle: the gymnocephalous, bi-ocellate, distome cercariae released by the snail Gabbia travancorica are ingested by the fish and develop directly into adults without undergoing a metacercarial stage of development. This is the first report of the genus Hapladena from India, and also the first report of the life cycle of the genus. 相似文献
18.
Abstract Ephedra comprises approximately 50 species, which are roughly equally distributed between the Old and New World deserts, but not in the intervening regions (amphitropical range). Great heterogeneity in the substitution rates of Gnetales (Ephedra, Gnetum, and Welwitschia) has made it difficult to infer the ages of the major divergence events in Ephedra, such as the timing of the Beringian disjunction in the genus and the entry into South America. Here, we use data from as many Gnetales species and genes as available from GenBank and from a recent study to investigate the timing of the major divergence events. Because of the tradeoff between the amount of missing data and taxon/gene sampling, we reduced the initial matrix of 265 accessions and 12 loci to 95 accessions and 10 loci, and further to 42 species (and 7736 aligned nucleotides) to achieve stationary distributions in the Bayesian molecular clock runs. Results from a relaxed clock with an uncorrelated rates model and fossil‐based calibration reveal that New World species are monophyletic and diverged from their mostly Asian sister clade some 30 mya, fitting with many other Beringian disjunctions. The split between the single North American and the single South American clade occurred approximately 25 mya, well before the closure of the Panamanian Isthmus. Overall, the biogeographic history of Ephedra appears dominated by long‐distance dispersal, but finer‐scale studies are needed to test this hypothesis. 相似文献
19.
The species–area relationship (SAR) is one of the most fundamental tools in ecology. After almost a century of quantitative ecology, however, the quest for a “best SAR model” still remains elusive, with a substantial uncertainty about the best fitting SAR model frequently being observed. Recent research has required that this uncertainty be addressed, and a multimodel SAR framework has been devised. Here we introduce the mmSAR R‐package, which is a flexible and scalable implementation of the multimodel SAR framework for species‐area datasets, and provide some examples of its use. This R‐package provides functions for fitting SAR models, performing model selection, and the build up of multimodel SARs. 相似文献
20.
Tomoko Sakai Hiroki Ohta Yuta Shintaku Naoto Kimura Yuki Ogawa Kazumi Sogabe Susumu Mori Hirotaka James Okano Yuzuru Hamada Shinsuke Shibata Hideyuki Okano Kenichi Oishi 《Primates; journal of primatology》2018,59(6):553-570
Advances in magnetic resonance imaging (MRI) and computational analysis technology have enabled comparisons among various primate brains in a three-dimensional electronic format. Results from comparative studies provide information about common features across primates and species-specific features of neuroanatomy. Investigation of various species of non-human primates is important for understanding such features, but the majority of comparative MRI studies have been based on experimental primates, such as common marmoset, macaques, and chimpanzee. A major obstacle has been the lack of a database that includes non-experimental primates’ brain MRIs. To facilitate scientific discoveries in the field of comparative neuroanatomy and brain evolution, we launched a collaborative project to develop an open-resource repository of non-human primate brain images obtained using ex vivo MRI. As an initial open resource, here we release a collection of structural MRI and diffusion tensor images obtained from 12 species: pygmy marmoset, owl monkey, white-fronted capuchin, crab-eating macaque, Japanese macaque, bonnet macaque, toque macaque, Sykes’ monkey, red-tailed monkey, Schmidt’s guenon, de Brazza’s guenon, and lar gibbon. Sixteen postmortem brain samples from the 12 species, stored in the Japan Monkey Centre (JMC), were scanned using a 9.4-T MRI scanner and made available through the JMC collaborative research program (http://www.j-monkey.jp/BIR/index_e.html). The expected significant contributions of the JMC Primates Brain Imaging Repository include (1) resources for comparative neuroscience research, (2) preservation of various primate brains, including those of endangered species, in a permanent digital form, (3) resources with higher resolution for identifying neuroanatomical features, compared to previous MRI atlases, (4) resources for optimizing methods of scanning large fixed brains, and (5) references for veterinary neuroradiology. User-initiated research projects beyond these contributions are also anticipated. 相似文献