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11.
TOSHIAKI SHIMIZU 《Invertebrate reproduction & development.》2013,57(3):221-224
Summary Development of the upper vas deferens and seminal vesicle, and the ecdysteroid titers of the cabbage armyworm (Mamestra brassicae) during pharate adult stage were investigated to provide evidence of endogenous control of the sperm movement through the reproductive tract. Apparently, development of the upper vas deferens is initiated when ecdysteroid titers increase after pupation and continues until eclosion. Sperm movement correlates with the decrease of ecdysteroid titers. When ecdysteroid titers remained at low levels, sperm release from the testis was observed one day before eclosion. 相似文献
12.
Abstract. 1. Females of the water strider Aquarius paludum insularis (Motschulsky) (Heteroptera: Gerridae) carry males on their backs and oviposit under water after copulation. This study focuses on the benefit A. paludum insularis receives by ovipositing in tandem.
2. Males guarded females in tandem through to the end of oviposition in 85% of copulations. Females in tandem dived deeper than single females, and the density of A. paludum insularis eggs increased with water depth. The proportion of eggs parasitized by a scelionid wasp, Tiphodytes gerriphagus Marchal (Hymenoptera: Scelionidae) decreased with increasing water depth.
3. These results suggest that during oviposition guarding by males is beneficial for females, because it enables pairs to dive and lay eggs deeper and in oviposition sites where the risk of egg parasitism is lower. 相似文献
2. Males guarded females in tandem through to the end of oviposition in 85% of copulations. Females in tandem dived deeper than single females, and the density of A. paludum insularis eggs increased with water depth. The proportion of eggs parasitized by a scelionid wasp, Tiphodytes gerriphagus Marchal (Hymenoptera: Scelionidae) decreased with increasing water depth.
3. These results suggest that during oviposition guarding by males is beneficial for females, because it enables pairs to dive and lay eggs deeper and in oviposition sites where the risk of egg parasitism is lower. 相似文献
13.
KEIKO KITAMURA KOSUKE HOMMA† HIDEKI TAKASU‡ SHINSUKE HAGIWARA§ FREDERICK H. UTECH¶ DENIS F. WHIGHAM†† SHOICHI KAWANO 《Plant Species Biology》2001,16(3):219-230
Populations of American beech in Virginia and the Great Smoky Mountain National Park in Tennessee and North Carolina were investigated for demographic genetic substructurings. Two Virginia populations, one on the Blue Ridge (WG1) and the other on the Piedmont (WG2) occur over an elevational gradient of several hundreds meters. One of the Great Smoky Mountain populations (GS1) was in a 'beech gap' and the other (GS2) in a 'cove forest' along a creek. The populations in the Great Smoky Mountain National Park were only separated by a few hundred meters in elevation, but both on the same physiographic province. The populations had two growth forms. Trees produced extensive root suckers at WG1, GS1 and GS2, but WG2 had no root suckers and all individuals had obviously been established from seeds. A total of 1335 shoots were mapped at the four sites, their size measured [diameter at breast height (DBH) or diameter at ground height (DGH)], and genotypes were determined for each locus using allozyme analysis. FIS among five different size-classes revealed an excess of homozygotes in WG1, GS1 and GS2, and an excess of heterozygotes in WG2. The offshoot formation from root suckers obviously contributed to the abundance of intermediate size-classes in WG1, GS1 and GS2. Exceedingly localized patchiness of different multilocus genotypes reveals genetic clustering of shoots that have obviously originated from root suckers in WG1, GS1 and GS2. The Piedmont population (WG2), on the other hand, showed loose localization of genetically related trees at a scale of 35–40 m in area, suggesting broader ranges of pollen and seed dispersal. The data are discussed in the light of the differences in growth form and mode of reproduction, and also in relation to the post-glacial migration and the current geographic distribution of the species. 相似文献
14.
JOHN H. GRAHAM KUNIO SHIMIZU JOHN M. EMLEN D. CARL FREEMAN JOHN MERKEL 《Biological journal of the Linnean Society. Linnean Society of London》2003,80(1):57-65
Multiplicative error accounts for much of the size-scaling and leptokurtosis in fluctuating asymmetry. It arises when growth involves the addition of tissue to that which is already present. Such errors are lognormally distributed. The distribution of the difference between two lognormal variates is leptokurtic. If those two variates are correlated, then the asymmetry variance will scale with size. Inert tissues typically exhibit additive error and have a gamma distribution. Although their asymmetry variance does not exhibit size-scaling, the distribution of the difference between two gamma variates is nevertheless leptokurtic. Measurement error is also additive, but has a normal distribution. Thus, the measurement of fluctuating asymmetry may involve the mixing of additive and multiplicative error. When errors are multiplicative, we recommend computing log E ( l ) − log E ( r ), the difference between the logarithms of the expected values of left and right sides, even when size-scaling is not obvious. If l and r are lognormally distributed, and measurement error is nil, the resulting distribution will be normal, and multiplicative error will not confound size-related changes in asymmetry. When errors are additive, such a transformation to remove size-scaling is unnecessary. Nevertheless, the distribution of l − r may still be leptokurtic. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80, 57–65. 相似文献
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17.
ONTOGENY OF CHICKEN HEMOGLOBIN II. CHROMATOGRAPHIC STUDY OF THE HETEROGENEITY OF HEMOGLOBIN IN DEVELOPMENT 总被引:1,自引:1,他引:0
KOJI SHIMIZU 《Development, growth & differentiation》1972,14(3):281-295
Some properties of the carbonmonoxyhemoglobin (HbCO) from chicken embryos of ages 5, 10 and 15 days of incubation, from 1-day posthatching and from adult chickens have been investigated by chromatography on carboxymethylcellulose (CM-cellulose) column and by starch gel electrophoresis.
Chromatogram of the hemoglobin (Hb) from 5-day chicken embryos has shown that it consists of at least 6 components. Starch gel electrophoresis of each isolated component from the column in phosphate (pH 6.8), in borate (pH 8.6) and in formate buffer (pH 1.9) has shown later that there are 3–4 embryonic type Hb components in 5-day embryos.
Chromatogram of the hemoglobin from adult chickens has shown that it consists of at least 4 components, but the examination of each isolated component from the column by electrophoresis in phosphate (pH 6.8), in borate (pH 8.6) and in formate buffer (pH 1.9) has shown that there are 4–6 adult type Hb components in adults.
In ontogenic process, embryonic Hb type is detectable in embryos up to 15 days of incubation. Fetal Hb type, which is not detectable in adult chickens, can be first found in 10-day embryos. 相似文献
Chromatogram of the hemoglobin (Hb) from 5-day chicken embryos has shown that it consists of at least 6 components. Starch gel electrophoresis of each isolated component from the column in phosphate (pH 6.8), in borate (pH 8.6) and in formate buffer (pH 1.9) has shown later that there are 3–4 embryonic type Hb components in 5-day embryos.
Chromatogram of the hemoglobin from adult chickens has shown that it consists of at least 4 components, but the examination of each isolated component from the column by electrophoresis in phosphate (pH 6.8), in borate (pH 8.6) and in formate buffer (pH 1.9) has shown that there are 4–6 adult type Hb components in adults.
In ontogenic process, embryonic Hb type is detectable in embryos up to 15 days of incubation. Fetal Hb type, which is not detectable in adult chickens, can be first found in 10-day embryos. 相似文献
18.
Molecular characterization of microbial communities in deep coal seam groundwater of northern Japan 总被引:2,自引:0,他引:2
We investigated microbial methanogenesis and community structure based on 16S rRNA gene sequences from a coal seam aquifer located 843–907 m below ground level in northern Japan; additionally, we studied the δ13C and δ2H (δD) of coal‐bed gases and other physicochemical parameters. Although isotopic analysis suggested a thermocatalytic origin for the gases, the microbial activity and community structure strongly implied the existence of methanogenic microbial communities in situ. Methane was generated in the enrichment cultures of the hydrogenotrophic and methylotrophic microorganisms obtained from coal seam groundwater. Methanogen clones dominated the archaeal 16S rRNA gene libraries and were mostly related to the hydrogenotrophic genus Methanoculleus and the methylotrophic genus Methanolobus. Bacterial 16S rRNA gene libraries were dominated by the clones related to the genera Acetobacterium and Syntrophus which have a symbiotic association with methanogens. LIBSHUFF analysis revealed that N2 gas injected into the coal seam (for enhanced methane production) does not affect the coverage of archaeal and bacterial populations. However, amova analysis does provide evidence for a change in the genetic diversity of archaeal populations that are dominated by methanogens. Therefore, N2 injection into the coal seam might affect the cycling of matter by methanogens in situ. 相似文献
19.
The life-history characteristics of Asarum caulescens Maxim. (Aristolochiaceae) are described here. This typical summer-green perennial of the Aristolochiaceae is a unique woodland element distributed in central Honshu, that is, south of Fukushima Prefecture to Shikoku and Kyushu, Japan. It grows in the somewhat shady understory of temperate montane deciduous broad-leaved or mixed forests associated with conifers, such as Cryptomeria japonica and Abies firma . One of the unique features of A. caulescens is its rhizome structures in combination with aerial shoots, which play an important role in vegetative propagation. The perennation strategy of A. caulescens is exceedingly complex, producing various combinations of linear or branched rhizomes bearing different numbers of leaves. Rhizomes consist of two or three segments, each 5 mm to 5 cm long as a unit, connected linearly, but also occasionally branched. At the tip of the newly formed rhizome segment, a single leaf or a pair of cordate leaves are formed. Exceedingly complex branching patterns of the rhizome segments were also recognized, forming ramets in late June to early July. Vegetative propagation by ramet formation obviously plays a very important role in the maintenance of local populations. 相似文献
20.
AKIRA SHIMIZU MARIUS WASBAUER YASUOKI TAKAMI 《Zoological Journal of the Linnean Society》2010,160(1):88-117
The Pompilidae (spider hunting wasps) show a marked diversity in their hunting and reproductive ecology, but difficulties in phylogenetic taxonomy have hindered the elucidation of their evolutionary processes. We present here a review of the hunting and reproductive ecology of the pepsine tribe Ageniellini (including the first prey record for Macromerella), and phylogenetic analyses of this group to reconstruct the evolution of nest‐constructing behaviour. The maximum parsimony and Bayesian inference analyses are based on 45 adult morphological characters, coded for 41 exemplar species, including five out‐group species, representing almost all the genera and subgenera in this tribe. Results supported the following eight clades uniting more than one genus: (1) Cyphononyx + Cryptocheilus + Ageniellini; (2) Ageniellini; (3) Auplopodina, containing Dimorphagenia, Auplopus, Machaerothrix, Phanagenia, Dichragenia, Paragenia, Macromerella, and Macromeris; (4) Phanagenia + Dichragenia + Auplopus artemis + Paragenia + Macromerella + Macromeris; (5) Auplopus artemis + Paragenia + Macromerella + Macromeris; (6) Paragenia + Macromerella + Macromeris; (7) Macromerella + Macromeris; and (8) Ageniella (Lissagenia) + Phanochilus. The monophyly of the genera Auplopus and Ageniella s.l. was not confirmed. The evolution of nesting behaviour was inferred, as burrowing in the soil without using water was ancestral in Ageniellini, and constructing nests by plastering mud obtained by softening soil with water was derived only once at the ancestor of the Auplopodina. The origin of cleptoparasitism was unclear. The origin of communal nesting is also discussed in relation to the evolution of nest‐constructing behaviour. The following new combinations are proposed: Ageniella (Alasagenia) sartoriana (Cresson) comb. nov. , Cyemagenia certator (Nurse) comb. nov. , and Auplopus artemis (Bingham) comb. nov. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 88–117. 相似文献