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1.
It was found that light accelerates the swelling of spinachchloroplasts suspended in a solution containing NaCl and Tris-HCl,and that, in about 60 min, the swollen chloroplasts begin toshrink rapidly. The volume of chloroplasts reached, on swelling,270 per cent of the original volume on the average and thenshrank to 17 per cent. The rate of swelling and the maximumvolume were affected markedly by the tonicity of NaCl. NH4Cldid not affect the volume changes, while phenazine methosulfateaccelerated the swelling remarkably. The relationship betweenphotoshrinkage and this light-induced high-amplitude swellingwas discussed. (Received April 2, 1966; )  相似文献   
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In a previous study based on 100 whole mitochondrial genome (mitogenome) sequences, we sought to provide a new perspective on the ordinal relationships of higher ray-finned fish (Actinopterygii). The study left unexplored the phylogenetic position of toadfishes (order Batrachoidiformes), as data were unavailable owing to technical difficulties. In the present study, we successfully determined mitogenomic sequences for two toadfish species ( Batrachomoeus trispinosus and Porichthys myriaster ) and found that the difficulties resulted from unusual gene arrangements and associated repetitive non-coding sequences. Unambiguously aligned, concatenated mitogenomic sequences (13 461 bp) from 102 higher actinopterygians (excluding the ND6 gene and control region) were divided into five partitions (1st, 2nd and 3rd codon positions of the protein-coding genes, tRNA genes and rRNA genes) and partitioned Bayesian analyses were conducted. The resultant phylogenies strongly suggest that the toadfishes are not members of relatively primitive higher actinopterygians (Paracanthopterygii), but belong to a crown group of actinopterygians (Percomorpha), as was demonstrated for ophidiiform eels (Ophidiiformes) and anglerfishes (Lophiiformes) in the previous study. We propose revised limits of major unranked categories for higher actinopterygians and a new name (Berycomorpha) for a clade comprising two reciprocally paraphyletic orders (Beryciformes and Stephanoberyciformes) based on the present mitogenomic phylogenies.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 289–306.  相似文献   
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A total of 49 novel polymorphic microsatellite markers in the ayu fish, Plecoglossus altivelis, were successfully isolated and characterized. The number of alleles per locus, observed heterozygosity, and expected heterozygosity ranged from two to 25 (11.3 on average), from 0.125 to 1.000 (0.648 on average), and from 0.123 to 0.957 (0.751 on average), respectively. These microsatellite markers will be useful for both studying population structure and identifying quantitative trait loci that control evolutionarily and economically important traits of ayu.  相似文献   
4.
Variation in the number of abdominal vs. caudal vertebrae is an important source of morphological diversification of fish. It is not clear, however, whether abdominal and caudal regions evolve independently. Regressions of offspring on parents demonstrated substantial additive genetic variation within populations, i.e. heritability, in both abdominal and caudal vertebral numbers of the medaka ( Oryzias latipes ). However, the heritability of caudal vertebrae tended to be smaller than that of abdominal vertebrae in some estimations, suggesting that abdominal and caudal regions are controlled by separate developmental modules. Furthermore, genetic correlation between abdominal and caudal vertebral numbers, estimated using full-sib family means, was negative but weak, supporting independent evolution. In addition, substantial genetic differentiation among populations was demonstrated in abdominal vertebral numbers, but not in caudal numbers. These results support our view that Jordan's rule, a geographical tendency for fish from higher latitudes to have more vertebrae, in this fish reflects local adaptations of abdominal vertebral numbers. In contrast, the low heritability of caudal vertebrae may reflect the intrinsic invariability of genes associated with a change in caudal vertebral numbers. This genetic constraint may have restricted morphological diversification of not only the medaka, but also the Order Beloniformes as a whole.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 867–874.  相似文献   
5.
Abstract.  1. In insect communities on fermented tree sap, agonistic interactions occur frequently among the component species. This study examined the effects of such interference competition on community structure and species co-occurrence on a spatio-temporally small scale.
2. Experimental removal of giant hornets ( Vespa mandarinia ), one of the most dominant species, showed no effect on either species richness or total abundance of the remaining insects. Significant increases in abundance were detected for five out of 19 taxa: V. ducalis , V. crabro , Lasius japonicus , Cryptarcha lewisi , and a group of micro sap beetles ( Epuraea spp., Haptoncus spp., and Haptoncurina spp.).
3. Behavioural observations indicated that interference did not alter the staying time at a patch (an exuding spot on a tree) for V. mandarinia , Rhomborrhina japonica , and Neope goschkevitschii . Interference-mediated departure from a patch was less frequent than departure without interference for all nine species observed, except for R. japonica . These behavioural contexts varied yearly for several species.
4. These results suggest that interference competition is a minor determinant of overall community structure, despite its conspicuousness. This weak effect of interference may be attributed to the short stay of dominant species and to individual behavioural responses, such as competitor avoidance. The variable influence of interference might be related to differences in species attributes, such as dominance hierarchies.  相似文献   
6.
To evaluate the effects on CO2 exchange of clearcutting a mixed forest and replacing it with a plantation, 4.5 years of continuous eddy covariance measurements of CO2 fluxes and soil respiration measurements were conducted in a conifer-broadleaf mixed forest in Hokkaido, Japan. The mixed forest was a weak carbon sink (net ecosystem exchange, −44 g C m−2 yr−1), and it became a large carbon source (569 g C m−2 yr−1) after clearcutting. However, the large emission in the harvest year rapidly decreased in the following 2 years (495 and 153 g C m−2 yr−1, respectively) as the gross primary production (GPP) increased, while the total ecosystem respiration (RE) remained relatively stable. The rapid increase in GPP was attributed to an increase in biomass and photosynthetic activity of Sasa dwarf bamboo, an understory species. Soil respiration increased in the 3 years following clearcutting, in the first year mainly owing to the change in the gap ratio of the forest, and in the following years because of increased root respiration by the bamboo. The ratio of soil respiration to RE increased from 44% in the forest to nearly 100% after clearcutting, and aboveground parts of the vegetation contributed little to the RE although the respiration chamber measurements showed heterogeneous soil condition after clearcutting.  相似文献   
7.
The classification of the Carassius complex (Cyprinidae) including all-female triploids, called ginbuna in Japanese, is so confused that three sympatric morphs of crucian carp in Lake Kasumigaura are categorized into two different subspecies within a species. We examined them in order to explain the coexistence of more than one subspecies and determine the founder of the triploid lineages in the crucian carp fauna in the lake. Principal component analysis proved that the three sympatric morphs had a morphometric basis distinguishable from each other. Ploidy was determined by flow cytometry which showed triploids in two morphs and diploids in the other morph. Stepwise discriminant analysis using only meristic characteristics could separate the diploids from the triploids. Phylogenetic analysis using mitochondrial DNA inferred two lineages in which one was composed of a triploid morph and the other was a diploid–triploid mixture. Disagreement between the taxonomic status and the phylogenetic status is explicable by assuming that the triploids in the Carassius complex had independent origins leading to the different subspecies. C. auratus langsdorfii appears to show genetic complexities that traditional taxonomic classification can not unravel.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79 , 351–357.  相似文献   
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The phylogenetic relationships of species are fundamental to any biological investigation, including all evolutionary studies. Accurate inferences of sister group relationships provide the researcher with an historical framework within which the attributes or geographic origin of species (or supraspecific groups) evolved. Taken out of this phylogenetic context, interpretations of evolutionary processes or origins, geographic distributions, or speciation rates and mechanisms, are subject to nothing less than a biological experiment without controls. Cypriniformes is the most diverse clade of freshwater fishes with estimates of diversity of nearly 3,500 species. These fishes display an amazing array of morphological, ecological, behavioral, and geographic diversity and offer a tremendous opportunity to enhance our understanding of the biotic and abiotic factors associated with diversification and adaptation to environments. Given the nearly global distribution of these fishes, they serve as an important model group for a plethora of biological investigations, including indicator species for future climatic changes. The occurrence of the zebrafish, Danio rerio, in this order makes this clade a critical component in understanding and predicting the relationship between mutagenesis and phenotypic expressions in vertebrates, including humans. With the tremendous diversity in Cypriniformes, our understanding of their phylogenetic relationships has not proceeded at an acceptable rate, despite a plethora of morphological and more recent molecular studies. Most studies are pre-Hennigian in origin or include relatively small numbers of taxa. Given that analyses of small numbers of taxa for molecular characters can be compromised by peculiarities of long-branch attraction and nodal-density effect, it is critical that significant progress in our understanding of the relationships of these important fishes occurs with increasing sampling of species to mitigate these potential problems. The recent Cypriniformes Tree of Life initiative is an effort to achieve this goal with morphological and molecular (mitochondrial and nuclear) data. In this early synthesis of our understanding of the phylogenetic relationships of these fishes, all types of data have contributed historically to improving our understanding, but not all analyses are complementary in taxon sampling, thus precluding direct understanding of the impact of taxon sampling on achieving accurate phylogenetic inferences. However, recent molecular studies do provide some insight and in some instances taxon sampling can be implicated as a variable that can influence sister group relationships. Other instances may also exist but without inclusion of more taxa for both mitochondrial and nuclear genes, one cannot distinguish between inferences being dictated by taxon sampling or the origins of the molecular data.  相似文献   
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