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101.
Patrilineal populations show more male transmission of reproductive success than cognatic populations in Central Asia,which reduces their genetic diversity 下载免费PDF全文
102.
《L'Anthropologie》2015,119(1):1-37
The most recent synthesis on the mortuary practices in the Middle Neolithic in Mediterranean France was published more than a decade ago. We propose to characterize those gestures focusing on the funerary nature of some inhumations discovered on domestic settlement. Two types of structures are distinguished. The first is composed of pits which function is exclusively related to funerary body or cremated bones deposit. Their features enable to consider that they are tombs. The domestic pits used as bodies or bones deposition constitute the second type. They are the most frequent in our corpus. Some of them display many features of the regular tombs but the configurations of most of those circular pits are difficult to interpret. Some alternative hypotheses are proposed to explain these particular body depositions. 相似文献
103.
Oviposition behaviour and larval development of Anastrepha fraterculus from Argentina in citrus 下载免费PDF全文
M.J. Ruiz M.L. Juárez R.A. Alzogaray F. Arrighi L. Arroyo G. Gastaminza E. Willink A. Bardón M.T. Vera 《Entomologia Experimentalis et Applicata》2015,157(2):198-213
Citrus peel physicochemical attributes are considered the main components conferring partial or even total resistance to fruit fly (Diptera: Tephritidae) infestation. Fruit fly females adapt their ovipositional strategies to overcome such resistance. Here, we explored the effects of citrus species (Rutaceae) on the ovipositional behaviour of the South American fruit fly, Anastrepha fraterculus (Wiedemann), and on its immature development. Particularly, we investigated the effects of (1) citrus species on oviposition behaviour and immature development, (2) citrus species on oviposition preference and on the location of the eggs at different depth in the citrus peel, and (3) harvest season and post‐harvest storage time on oviposition behaviour and immature development in lemon. Citrus species influenced ovipositional behaviour and affected survival of immature stages. Females laid eggs in lemon [Citrus limon (L.) Burm.], orange [Citrus sinensis (L.) Osbeck], and grapefruit (Citrus paradisi Macfadyen). In orange and lemon, larvae were found dead close to the oviposition areas, suggesting chemically mediated resistance mechanisms. Under choice conditions, females preferred grapefruit over lemon and bigger clutches were found in the layers where embryonic development is favoured. Unsuitability of lemon as a medium to complete development was neither affected by harvest season nor by storage time of the fruit after harvest. The physical and chemical characteristics of the peel were distinctive to each citrus species and may have affected the specific levels of resistance of these citrus species to infestation by A. fraterculus. 相似文献
104.
Evolution of bilaterally asymmetrical larvae in freshwater mussels (Bivalvia: Unionoida: Unionidae) 下载免费PDF全文
Bilaterally asymmetrical glochidia (i.e. bivalved parasitic larvae bearing a large marginal appendage on a single valve) have been reported from five Asian freshwater mussel genera belonging to two separate subfamilies, the Gonideinae (i.e. Pseudodon, Solenaia, and Physunio) and Rectidentinae (i.e. Contradens and Trapezoideus). This classification requires that the bilaterally asymmetrical glochidium‐bearing mussels are not monophyletic, and suggests that this atypical larval morphology evolved twice in the same geographic region. Although homoplastic glochidium characters are known (e.g. marginal appendages and size), we hypothesized that bilaterally asymmetrical glochidia represent a novel morphological synapomorphy. We tested the monophyly of the mussels bearing bilaterally asymmetrical glochidia using a molecular matrix consisting of representatives from all six freshwater mussel families and three molecular markers (28S, 16S, and COI). Bayesian inference, maximum likelihood, and ancestral state reconstruction were employed to estimate the phylogeny and larval trait transformations. The reconstructed phylogeny rejects the monophyly of the asymmetrical glochidium‐bearing mussels and resolves two putative origins of asymmetrical glochidia; however, ancestral state reconstruction supports asymmetrical glochidia as a synapomorphy of only one supraspecific taxon of the Rectidentinae. In the Gonideinae, asymmetrical glochidia were autapomorphic of Pseudodon cambodjensis (Petit, 1865). That is, no other taxa resolved among the Gonideinae had bilaterally asymmetrical glochidia, including other Pseudodon species. We describe how the alleged intrageneric glochidial variation in Pseudodon, and in the other genera of the Gonideinae reported to have asymmetrical glochidia (i.e. Solenaia and Physunio), challenge the resolved convergence of asymmetrical glochidia. Our results are discussed in the context of freshwater mussel larval evolution, patterns in life‐history traits, and the classification of freshwater mussels generally. © 2015 The Linnean Society of London 相似文献
105.
Background
In order to understand feeding ecology and habitat use of coral reef fish, fatty acid composition was examined in five coral reef fishes, Thalassoma lunare, Lutjanus lutjanus, Abudefduf bengalensis, Scarus rivulatus and Scolopsis affinis collected in the Bidong Island of Malaysian South China Sea.Results
Proportions of saturated fatty acids (SAFA) ranged 57.2% 74.2%, with the highest proportions in fatty acids, the second highest was monounsaturated fatty acids (MUFA) ranged from 21.4% to 39.0% and the proportion of polyunsaturated fatty acids (PUFA) was the lowest ranged from 2.8% to 14.1%. Each fatty acid composition differed among fishes, suggesting diverse feeding ecology, habitat use and migration during the fishes’ life history in the coral reef habitats.Conclusions
Diets of the coral fish species might vary among species in spite of that each species are living sympatrically. Differences in fatty acid profiles might not just be considered with respect to the diets, but might be based on the habitat and migration. 相似文献106.
The “Hill” equation for co-operative binding-systems has been extended to describe the effect of substrate-analogue on the binding of substrate to an oligomeric protein. It is demonstrated that the more negatively co-operative the binding-system, the more sensitive is the binding of substrate to inhibition by increases in the relative concentration of substrate-analogue. It is proposed that the physiological significance of negative co-operativity for enzymes may be complementary to the physiological significance of positive co-operativity. The effect of negative co-operativity is to make substrate binding more sensitive to inhibition by relative increases in the concentration of substrate-analogue (e.g. for many enzymes product of the reaction) at the expense of decreased sensitivity of substrate binding to relative changes in substrate concentration compared to a system with equivalent, independent substrate binding sites. In contrast, the effect of positive co-operativity is to make the enzyme more sensitive to relative changes in substrate concentration at the expense of decreased sensitivity to inhibition by relative increases in product concentration, compared to an enzyme without co-operative binding. 相似文献
107.
Rat ventral prostate nucleoli contain protein phosphokinase(s) which have distinctly different characteristics from protein phosphokinase(s) localized in the extra-nucleolar regions of the nucleus. The differences pertain to pH vs activity profiles and activation by divalent cations, utilizing dephospho-phosvitin as substrate. Lysine-rich and arginine-rich F3 histones are also phosphorylated by nucleolar protein phosphokinase(s). Phosphorylation of histones by either nucleolar or extra-nucleolar fractions was not stimulated by cAMP, whereas that of phosvitin was slightly inhibited. 相似文献
108.
Yong-Shik Kim 《Landscape and Ecological Engineering》2006,2(2):163-170
Korea is a land of contrasts. The mountainous Korean peninsula arches north and northwest towards the Russian and Chinese borders, where the last areas of old growth coniferous forest and the land formed five forest types. Plant and habitat diversity in Korea has been largely damaged by various kinds of human activities. The plant diversity of Korea is severely threatened due to the high population density and rapid industrialization since the 1960s, as well as the illegal collection of wild plants for ornamental, medicinal, and food purposes. Natural areas have been greatly fragmented and survive only as ecological islands surrounded by modified cultivated and industrial lands. For instance, more than 60 industrial parks are located along the coast, and these have contributed to the rapid destruction of plant diversity in the coastal areas of the peninsula. The modern concept of plant conservation in Korea is still in an infant stage. The cooperation of plant conservation bodies with disciplinary approaches based on conservation biology are essential strategies to pursue plant conservation. The capacity building for plant conservation in Korea has different management regimes by the relevant ministries. Since the late 1990s, the plant conservation body Korean Plant Specialist Group of the International Union for the Conservation of Nature and Natural Resources Species Survival Commission (IUCN SSC) has been closely linked with international conservation bodies for in situ and ex situ conservation management. Under the umbrella of the national plant conservation strategies, the different strategies and working agencies can be fully integrated. Furthermore, the systematic approaches for the recovery of threatened species, as well as habitat monitoring over the long-term basis, will need to be supported by a stable budget policy. Also, protocol for the conservation of rare and endangered plant species, including recovery works in Korea, is strongly needed. 相似文献
109.
ROGER N. HUGHES 《Zoological Journal of the Linnean Society》1979,65(2):111-118
L. africana and L. knysnaensis are regarded as two morphs of a single species which exhibits a genetic cline along the south-eastern coast of southern Africa. The dark brown morph knysnaensis dominates the western, cooler end of the cline and is replaced by the pale blue morph africana at the warmer end of the cline. These conclusions are based on evidence from the latitudinal distributions, the complete range of intermediate forms regarding shell colour and shell morphology and the lack of differences in redular morphology, penial morphology or habitat. 相似文献
110.
Amirah Hurzaid Tin-Yam Chan Siti Azizah Mohd Nor Zainal Abidin Muchlisin Wei-Jen Chen 《Zoologica scripta》2020,49(5):596-613
The decapod family Penaeidae comprises most of the economically important marine shrimp species. Its members are widespread throughout the world, with its highest species diversity centred in the Indo-West Pacific region. Despite this importance, their taxonomy, classification and phylogeny are not yet settled due in part to incongruence among hypotheses proposed from molecular versus morphological studies. In this study, using a thorough taxonomic sampling of especially the South-East Asian species, we aim to (a) utilize a reconstructed phylogeny to test the monophyly of the Penaeidae and its currently recognized genera and (b) explore its species diversity in South-East Asian waters. To infer the phylogeny, a combined gene data set (including 109 ingroup and six outgroup taxa) of mitochondrial genes, COI and 16S rRNA, and two nuclear genes, NaK and PEPCK, was utilized. To explore its diversity, another data set that included 371 COI gene sequences (231 newly generated and 140 retrieved from public sources) was compiled and subsequently analysed with two different tools (ABGD and bPTP) for species delimitation. Other than supporting the non-monophyly of the Penaeidae with the Sicyoniidae nested within the penaeid tribe Trachypenaeini, the genera Penaeus, Mierspenaeopsis and Parapenaeopsis were also revealed to be polyphyletic. Our species delimitation analysis inferred that 94 putative species actually existed within the 71 morphospecies reviewed, indicating an underestimated biodiversity in this family and the potential presence of new species within the following morphospecies: Kishinouyepenaeopsis cornuta, K. incisa, Mierspenaeopsis sculptilis, M hardwicki, Parapenaeopsis coromandelica and Penaeus monodon. 相似文献