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Andrija Smelcerovic Michael Spiteller Axel Patrick Ligon Zaklina Smelcerovic Nils Raabe 《Biochemical Systematics and Ecology》2007
The essential oils of the aerial parts of nine species of Hypericum (Hypericum barbatum, Hypericum hirsutum, Hypericum linarioides, Hypericum maculatum, Hypericum olympicum, Hypericum perforatum, Hypericum richeri, Hypericum rumeliacum and Hypericum tetrapterum), collected from different locations in Southeast Serbia, were obtained by steam distillation and analyzed by GC and GC–MS. The essential oils investigated were characterized by a high content of non-terpene compounds and a low content of monoterpenes. The contents of non-terpenes, monoterpenes and sesquiterpenes in oils of the species H. barbatum, H. richeri and H. rumeliacum (section Drosocaprium) were similar and these oils were characterized by high contents of fatty acids. The oils of H. hirsutum and H. linarioides (section Taeniocarpium) contained a high percentage of n-nonane. There were similarities in contents of non-terpenes and sesquiterpenes in oils of species that belong to the section Hypericum (H. maculatum, H. perforatum and H. tetrapterum). The oil of H. olympicum differed from others by higher terpene content. A comparison was also carried out of the chemical composition of the essential oils from flower, leaf and stem of H. perforatum and it revealed that the highest concentration of non-terpene compounds was found in the flower and stem oil, while a high concentration of sesquiterpenes was characteristic for leaf oil. There were significant differences in the concentrations of the same compounds in the essential oils of H. maculatum, H. olympicum and H. perforatum, collected in different years from the same location which could be explained by seasonal differences. All data were statistically processed with principal component analysis and cluster analysis. The main conclusion from the above data is that genetic and environmental factors both play a role in determining the composition of essential oils of the Hypericum species studied. 相似文献
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The origin of Hordelymus genome has been debated for years, and no consensus conclusion was reached. In this study, we sequenced and analyzed the RPB2 (RNA polymerase subunit II) gene from Hordelymus europaeus (L.) Harz, and its potential diploid ancestor species those were suggested in previous studies. The focus of this study was to examine the phylogenetic relationship of Hordelymus genomes with its potential donor Hordeum, Psathyrostachys, and Taeniatherum species. Two distinguishable copies of sequences were obtained from H. europaeus. The obvious difference between the two copies of sequences is a 24 bp indel (insertion/deletion). Phylogenetic analysis showed a strong affinity between Hordeum genome and Hordelymus with 85% bootstrap support. These results suggested that one genome in tetraploid H. europaeus closely related to the genome in Hordeum species. Another genome in H. europaeus is sister to the genomes in Triticeae species examined here, which corresponds well with the recently published EF-G data. No obvious relationship was found between Hordelymus and either Ta genome donor, Taeniatherum caput-medusae or Ns genome donor, Psathyrostachys juncea. Our data does not support the presence of Ta and Ns genome in H. europaeus, and further confirms that H. europaeus is allopolyploid. 相似文献
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A species of seagrass in the genus Halophila was found growing in a shallow lagoon on the west shore of Antigua in the Caribbean West Indies. Genetic analysis showed the plants were Halophila ovalis. In addition, the samples had no genetic deviation (using nrDNA sequences) from Halophila johnsonii, considered to be an endemic and endangered species in Florida, USA. Morphological analysis demonstrated the Antiguan Halophila to be well within the range of plant characteristics previously described in the literature for H. ovalis, except for leaf width and number of seeds per fruit, and again, not different from H. johnsonii and very closely related to H. ovalis from the Indo-Pacific. Ours is the first report of H. ovalis in the Tropical Atlantic bioregion. 相似文献
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The genetic variability of 12 burrowing nematode (Radopholus sp.) isolates from Central America, the Caribbean, and Florida, and one isolate from Ivory Coast were compared with RAPD analysis. A high degree of genetic similarity (>0.82) was determined for isolates from the Western Hemisphere. Genome similarity was greatest among isolates collected within a country. Among isolates collected in Central America and the Caribbean, burrowing nematodes from Belize and Guatemala were genetically more distant. However, the genome of the isolate from Ivory Coast was most dissimilar (>0.30). These results suggest that African and American burrowing-nematode isolates may have had different origins or that they have been geographically isolated for a sufficient amount of time to have accumulated genetic changes detectable by RAPD analysis. No relationship was found between the genomic similarity and extent of reproduction or damage to banana or citrus roots. Morphometric analysis involving eight of the isolates indicated that they were morphologically identical and values for morphometric parameters were well within the range previously published for banana and citrusparasitic burrowing nematodes. 相似文献
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Starch grains are a ubiquitous component of plants that have been used in tandem with phytoliths, pollen, and macrofossils to reconstruct past floral diversity. This tool has yet to be fully explored for aquatic plants, specifically seagrasses, which lack phytoliths and are rarely preserved as macrofossils or pollen. If starch grains in seagrasses are morphologically distinct, this method has the potential to improve seagrass identification in the fossil record in such cases where its starch is preserved (e.g. scratches and occlusal surfaces of tooth enamel from seagrass consumers). The goals of this study were twofold: (1) to determine if starch is present in seagrass material and (2) to assess how starch grain morphology differs between different seagrasses.This study focused on four abundant and ecologically distinct seagrasses from the Caribbean: Halodule wrightii, Ruppia maritima, Syringodium filiforme, and Thalassia testudinum. Starch grains were observed in all species except S. filiforme. Grains from H. wrightii are typically observed in side-on orientation, are sub-round to angular, and are fairly small (3-19 μm, end-on). Grains of R. maritima are small spherical grains (4-8 μm) that have a centric hilum and a straight extinction cross with a median angle between the arms of 90°. Grains from T. testudinum are large (9-31 μm, end-on), conical in side-on and round/sub-round in end-on orientation, have a slightly eccentric hilum with an obvious particle, and prominent lamellae.Visual assessment and comparative statistics demonstrate that the morphology of starch grains from T. testudinum, R. maritima, and H. wrightii are significantly different. With more extensive research, there is potential for the positive identification of starch grains from an unknown seagrass. The ability to identify seagrass from starch grains could facilitate the identification of seagrasses in the fossil record and supply information on seagrass evolution and distribution, climate effects on seagrass distribution, and the diets of seagrass consumers. 相似文献
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在新疆古尔班通古特沙漠中的梭梭、白梭梭上发现由木虱引起的叶苞状虫瘿,发生率达到90%以上,虫瘿内有4种木虱:异色胖木虱(Caillardia robusta Loginova)、梭梭胖木虱(C. azurea Loginova)、矮胖木虱(C. nana Loginova)和显赫胖木虱(C. notata Loginova),后两种为中国新记录种。木虱在梭梭上1a发生两个高峰,丘间低地发生最为严重,沙丘边缘与砾石荒漠发生量相差不大,在5月中旬和6月中旬达到高峰期;木虱在白梭梭上1a发生两个高峰,低丘比高丘发生严重,阳坡比阴坡发生严重,在6月中旬和7月底8月初达到高峰期。梭梭和白梭梭上树龄越大虫瘿发生越严重。地势、树势、方位及地势、坡面对木虱虫瘿的发生都存在显著性影响,但是它们互作对木虱虫瘿的影响却不大。通过研究古尔班通古特沙漠梭梭和白梭梭上木虱虫瘿的发生规律及其与周边环境的关系,为保护荒漠生态环境提供依据。 相似文献
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The announcement of a new species, Homo floresiensis, a primitive hominin that survived until relatively recent times is an enormous challenge to paradigms of human evolution. Until this announcement, the dominant paradigm stipulated that: 1) only more derived hominins had emerged from Africa, and 2) H. sapiens was the only hominin since the demise of Homo erectus and Homo neanderthalensis. Resistance to H. floresiensis has been intense, and debate centers on two sets of competing hypotheses: 1) that it is a primitive hominin, and 2) that it is a modern human, either a pygmoid form or a pathological individual. Despite a range of analytical techniques having been applied to the question, no resolution has been reached. Here, we use cladistic analysis, a tool that has not, until now, been applied to the problem, to establish the phylogenetic position of the species. Our results produce two equally parsimonious phylogenetic trees. The first suggests that H. floresiensis is an early hominin that emerged after Homo rudolfensis (1.86 Ma) but before H. habilis (1.66 Ma, or after 1.9 Ma if the earlier chronology for H. habilis is retained). The second tree indicates H. floresiensis branched after Homo habilis. 相似文献
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Tilo Nadler Ulrike StreicherClara Stefen Elke SchwierzChristian Roos 《Der Zoologische Garten (in deutscher Sprache / in German)》2011,80(5):271-286
Ferret-badgers, genus Melogale, are distributed in the Indochinese region, Java, Bali and NE-Borneo. There are currently four species described each having very similar phenotypes. In March 2005, a living ferret-badger of a different phenotype was confiscated by rangers from Cuc Phuong National Park, Vietnam. This individual died and the carcass was not preserved. In January 2006, a newly deceased individual of the same phenotype was found at the Endangered Primate Rescue Center, Cuc Phuong National Park. Due to several different characteristics these individuals vary greatly from the current species. Thus, we describe an additional species, M. cucphuongensis sp. nov. from northern Vietnam, which occurs sympatrically with M. moschata and M. personata, but differs from both species clearly in skull morphology and other features.Based on a 423 bp-long fragment of the mitochondrial cytochrome b gene, M. cucphuongensis sp. nov. is a member of the genus Melogale and represents a sister lineage to a clade consisting of M. personata and M. moschata. 相似文献
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Cüneyt Çirak Birsen Sağlam Ali Kemal Ayan Kudret Kevseroğlu 《Biochemical Systematics and Ecology》2006
The genus Hypericum has received considerable interest from scientists, as it is a source of a variety of biologically active compounds including the hypericins. The present study was conducted to determine ontogenetic, morphogenetic and diurnal variation of the total hypericins content in some species of Hypericum growing in Turkey namely, Hypericum aviculariifolium subsp. depilatum var. depilatum (endemic), Hypericum perforatum and Hypericum pruinatum. The Hypericum plants were harvested from wild populations at vegetative, floral budding, full flowering, fresh fruiting and mature fruiting stages four times a day. Plants were dissected into stem, leaf and reproductive tissues, which were dried separately, and subsequently assayed for total hypericin content. The density of dark glands on leaves at full flowering plants was determined for each species. Floral parts had the highest hypericin content in all species tested. But diurnal fluctuation in the hypericin content of whole plant during the course of ontogenesis varied among the species. It reached the highest level at floral budding and tended to increase at night in H. aviculariifolium subsp. depilatum var. depilatum and H. pruinatum, whereas in H. perforatum hypericin content was the highest at full flowering and no diurnal fluctuation was observed. In general, hypericin content of leaves and whole plant was higher in H. aviculariifolium subsp. depilatum var. depilatum whose leaves had more numerous dark glands than those of the two other species. 相似文献
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In 2004, a new hominin species, Homo floresiensis, was described from Late Pleistocene cave deposits at Liang Bua, Flores. H. floresiensis was remarkable for its small body-size, endocranial volume in the chimpanzee range, limb proportions and skeletal robusticity similar to Pliocene Australopithecus, and a skeletal morphology with a distinctive combination of symplesiomorphic, derived, and unique traits. Critics of H. floresiensis as a novel species have argued that the Pleistocene skeletons from Liang Bua either fall within the range of living Australomelanesians, exhibit the attributes of growth disorders found in modern humans, or a combination of both. Here we describe the morphology of the LB1, LB2, and LB6 mandibles and mandibular teeth from Liang Bua. Morphological and metrical comparisons of the mandibles demonstrate that they share a distinctive suite of traits that place them outside both the H. sapiens and H. erectus ranges of variation. While having the derived molar size of later Homo, the symphyseal, corpus, ramus, and premolar morphologies share similarities with both Australopithecus and early Homo. When the mandibles are considered with the existing evidence for cranial and postcranial anatomy, limb proportions, and the functional anatomy of the wrist and shoulder, they are in many respects closer to African early Homo or Australopithecus than to later Homo. Taken together, this evidence suggests that the ancestors of H. floresiensis left Africa before the evolution of H. erectus, as defined by the Dmanisi and East African evidence. 相似文献
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Linda J Walters Celia M SmithJames A Coyer Cynthia L HunterKevin S Beach Peter S Vroom 《Journal of experimental marine biology and ecology》2002,278(1):47-65
Siphonous, green macroalgae of the genus Halimeda are ubiquitous and ecologically important in tropical and subtropical marine environments. It has been hypothesized that the abundance of Halimeda on coral reefs is in part due to the ability of this genus to propagate asexually via vegetative fragmentation. However, vegetative fragmentation has only been documented for H. discoidea in a laboratory setting. To test the hypothesis that vegetative fragmentation contributes to field populations of Halimeda, we examined three aspects of fragmentation by H. tuna (Ellis and Solander) Lamouroux, H. opuntia (Linneaus) Lamouroux and H. goreaui Taylor on Conch Reef in the Florida Keys: (1) short-term (8 days) and long-term (14 weeks) fragment survival and rhizoid production in the laboratory and field (7 and 21 m), (2) size of the fragment pool and (3) influences of herbivory and water motion on production and dispersal of fragments. Although morphologically similar to H. discoidea, only a small percentage of H. tuna fragments survived. Fragments of H. opuntia and H. goreaui were more robust, and survival and rhizoid production were positively correlated with size in short-term trials. In 14-week field trials, one-third or fewer fragments of any species survived at 7 m, potentially because fragments were covered by large amounts of sediment. Survivors included some buried, seemingly dead individuals that turned green when exposed to light, highlighting the remarkable ability of this genus to survive disturbances. There was much less sediment accumulation at 21 m, where more fragments survived. Most (93%) eight-segment fragments of H. opuntia produced attachment rhizoids by the end of the 14-week trial. Overall, a range of 4.7-9.4 fragments of Halimeda m−2 day−1 were found on Conch Reef; most fragments were generated by H. goreaui. Fish bite marks were evident on 75-85% of the individuals of H. tuna and the number of bites per thallus ranged from 1 to 23. Herbivorous reef fish commonly fed on all three species of Halimeda. Some fish consumed the biomass, while others rejected most bites. For example, 83% of bites were rejected by the blue-striped grunt. Dispersal distances for rejected bites ranged from 0 to 31 m. Water motion was also responsible for fragment dispersal; experimentally produced fragments moved up to 48 cm day−1. Results presented here suggest that asexual propagation of fragments of Halimeda is an important component of the life-history of this genus and vegetative fragmentation contributes to the abundance of this genus on coral reefs. 相似文献
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Tea production in North-East India hit a record loss due to the widespread severe outbreak of a mixed brood of three species of looper caterpillar pests of geometrid moths (Lepidoptera) in 2008-2010. In addition to Buzura suppressaria, two newly recorded geometrids, viz., Hyposidra infixaria and Hyposidra talaca have caused widespread severe damage in recent years. In the present study we report the nucleopolyhedroviruses (NPV) isolated from the tea looper caterpillar from North-East India. We identified and characterized the NPV by cloning and sequencing a partial segment of polyhedrin gene of virus infected larvae of B. suppressaria, H. talaca and H. infixaria. A comparison of deduced amino acids of polyhedrin gene among H. talaca, H. infixaria and B. suppressaria showed that same strain was found to infect all the three loopers in India, which show high sequence identity with B. suppressaria Chinese isolates. Based on the polyhedrin sequence homology, it is predicted that a variant of B. suppressaria Chinese isolate of NPV found to infect H. talaca, H. infixaria and B. suppressaria in India. 相似文献
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A microsporidium from Hippodamia convergens was transmitted horizontally to three non-target coccinellid hosts (Adalia bipunctata L., Coccinella septempunctata L. and Harmonia axyridis Pallas) under laboratory conditions. For all species examined, microsporidia-infected larvae took significantly longer to develop than did uninfected larvae but the microsporidium had no effect on larval mortality. Adult sex ratios of uninfected and microsporidia-infected adults were about 1:1 (♀:♂) and did not differ significantly. At the end of a 90-day trial, microsporidia-infected H. convergens produced significantly fewer eggs and did not live as long as uninfected individuals. Differences in fecundity and longevity were not observed for the three non-target coccinellids that were examined. Mean spore counts from smear preparations of microsporidia-infected A. bipunctata did not differ significantly from H. convergens, suggesting that A. bipunctata (a native coccinellid) is a suitable host for the microsporidium but infection was lighter in C. septempunctata and H. axyridis (introduced species). Vertical transmission of the pathogen was observed during the 90-day trial by examining eggs and larvae that were produced by microsporidia-infected adults. For all species examined, 100% vertical transmission of the pathogen was eventually observed. Three eugregarines were found in two adult A. bipunctata: Gregarine A trophozoites are similar in size to those of Gregarina katherina Watson (described earlier from Coccinella spp.), Gregarine B trophozoites are similar in size to those of Gregarine A but are morphology distinct, and Gregarine C trophozoites are similar in size to G. barbarara Watson (described earlier from A. bipunctata). 相似文献
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A new species of Caponiidae, Tarsonops irataylori
sp. n. is described from southern Belize, and a key to the genera of the subfamily Nopinae is provided. 相似文献
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To better understand the differences in the efficacy of entomopathogenic nematode species against white grub species, we are studying the various steps of the infection process of entomopathogenic nematodes into different white grub species using nematode species/strains with particular promise as white grub control agents. In this study we compared the attraction of the entomopathogenic nematodes Steinernema scarabaei (AMK001 strain), Steinernema glaseri (NC1 strain), Heterorhabditis zealandica (X1 strain), and Heterorhabditis bacteriophora (GPS11 strain) to third-instars of the scarabs Popillia japonica, Anomala orientalis, Cyclocephala borealis, and Rhizotrogus majalis, and late-instar greater wax moth, Galleria mellonella, larvae. Individual larvae were confined at the bottom of 5.5 cm vertical sand columns, nematodes added to the sand surface after 24 h, and nematodes extracted after another 24 h. Nematode attraction to hosts was strongly affected by nematode species but the effect of insect species varied with nematode species. S. glaseri had a high innate dispersal rate (i.e., in absence of insects) and was strongly attracted to insects without significant differences among insect species. S. scarabaei had a very low innate dispersal rate so that even a strong relative response to insects resulted in low absolute dispersal rates toward insects. S. scarabaei tended to be most attracted to G. mellonella and least attracted to C. borealis. H. zealandica had a high innate dispersal rate but only responded weakly to insects without significant differences among species. H. bacteriophora had limited innate dispersal and only weakly responded to insects with G. mellonella tending to be the most attractive and C. borealis the least attractive insect. It has to be noted that we cannot exclude that the use of different rearing hosts (A. orientalis and P. japonica larvae for S. scarabaei, G. mellonella larvae for the other nematodes) might have had an impact on the nematodes dispersal and relative attraction behavior. This study indicates that host attractiveness and nematode dispersal rates may contribute but do not play a major role in the variability in white grub susceptibility and/or nematode virulence. 相似文献
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Masumeh Khodaverdi Ali Movafeghi Mohammed Reza Dadpour Somayeh Naghiloo Masoud Ranjbar Gerhard Prenner 《Flora》2014
Floral initiation and development of Hedysarum varium, Onobrychis melanotricha and Alhagi persarum was studied using epi-illumination light-microscopy techniques. The studied species belong to the tribe Hedysareae of the inverted repeat loss clade (IRLC clade), which is characterized by missing the large inverted repeat in the chloroplast genome. The main aim of our study was to determine developmental bases for similarities and differences among the three taxa and to verify the position of Alhagi relative to other genera of the IRLC clade. According to our observations, bracteoles are missing in Onobrychis melanotricha, but are present in the other two species. All three species share unidirectional sepal initiation starting with a median abaxial sepal and bidirectional petal initiation. Stamen initiation is unidirectional in all except in the outer stamen whorl of Hedysarum varium, where it is bidirectional. An important ontogenetic feature in O. melanotricha is the existence of five common primordia, which give rise to petal and stamen primordia. Although in H. varium and O. melanotricha common primordia are observed at some stages in floral organ initiations, in Alhagi all organs are initiated separately. Moreover, overlap in time of floral organs initiation occurs in H. varium and O. melanotricha, but not in A. persarum. The carpel initiates concurrently with the petal primordia in all. It might be presumed that Alhagi is primitive in relation to the other studied Hedysareae taxa, due to the presence of bracteoles, the absence of common primordia, and the lack of overlap in time of different organ initiations. 相似文献
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Jennifer Dijkstra Larry G. Harris Erica Westerman 《Journal of experimental marine biology and ecology》2007,342(1):61-68
Invasive ascidians are a growing concern for ecologists and natural resource managers, yet few studies have documented their short- and long-term temporal patterns of abundance. This study focuses on the invasion of the Gulf of Maine by the colonial ascidians Botryllus schlosseri, Botrylloides violaceus, Diplosoma listerianum and Didemnum sp. A. We examined the time of arrival and potential vectors for these four invasive ascidians using survey data (collected from 1969 onwards) and literature documentation. We also compared the dominance and seasonal patterns of abundance of these species using data from two identical panel studies; one conducted from 1979 to 1980, the other from 2003 to 2005. Didemnum and Botrylloides were most likely first introduced into the Damariscotta River, Maine in the early 1970's through oyster aquaculture while Botryllus and Diplosoma were probably transported by commercial and recreational vessels. The overall abundance of colonial ascidians has increased since 1979 and 1980. Botryllus was the only invasive colonial ascidian present during the 1979 to 1980 study and accounted for an average of 6.16% cover on panels. From 2003 to 2005, the more recently arrived colonial ascidians Botrylloides and Didemnum accounted for 7.38% and 2.08% cover respectively, while Botryllus covered only 1.16%. Our results reveal a shift in seasonal abundance between 1979 to 1980 and 2003 to 2004. In 1979 and 1980, colonial ascidians had the highest percent cover in fall and winter while in 2003 and 2005 they had highest percent cover in summer and fall. Seasonal patterns of space occupation by colonial ascidians were correlated with seasonal changes in seawater temperature. 相似文献
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Using French Grunts (Haemulon flavolineatum) held captive within mangrove and reef sites, we determined (a) whether otolith microchemical differences existed between mangroves and reefs separated at a biologically relevant spatial scale (0.25-7.1 km), (b) whether patterns in elemental concentrations were consistent across years, and (c) whether it was possible to identify whether a given fish occupied a mangrove as a juvenile.Three sites were established at Great Exuma, Bahamas (two reefs and one mangrove, May 2001) and at Turneffe Atoll, Belize (one reef and two mangroves, August 2001 and 2002). Using concentrations of Sr and Ba, discriminant function analysis (DFA) indicated unique spatial microchemical signatures of fish from each of the three Bahamas sites allowing an average correct classification of 77%. Using concentrations of Sr, Ba, Sn and Pb (2001), and in addition Li, Mg, Cu and Rb (2002), DFA of the three Belize sites indicated an average correct classification of 68% and 85% in 2001 and 2002, respectively. To assess temporal variability in otolith microchemistry, we compared microchemical signatures of Belize fish from 2001 to those from 2002. On average, 42% of fish from 2002 were correctly classified to their captive sites using chemical information from 2001, thus suggesting considerable temporal variability in otolith microchemistry. Finally, to identify whether a given fish occupied a mangrove during its juvenile stage, we ablated the juvenile portion of the otolith taken from reefs in Belize 2002. Results of this analysis indicated that 36% of 39 individuals taken from the reef had a signature more representative of one of the mangrove sites. Although otolith microchemistry varied temporally and our analysis was restricted to the grouping of individuals to only one of three sites, mangroves appeared to contribute to reef populations. 相似文献