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Registros recuperados: 176 | |
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Hou,Zhaoqi; Jia,Bing; Li,Fei; Liu,Pu; Liu,Li; Ye,Zhenfeng; Zhu,Liwu; Wang,Qi; Heng,Wei. |
Abstract The plant genes encoding ABCGs that have been identified to date play a role in suberin formation in response to abiotic and biotic stress. In the present study, 80 ABCG genes were identified in ‘Dangshansuli’ Chinese white pear and designated as PbABCGs. Based on the structural characteristics and phylogenetic analysis, the PbABCG family genes could be classified into seven main groups: classes A-G. Segmental and dispersed duplications were the primary forces underlying the PbABCG gene family expansion in ‘Dangshansuli’ pear. Most of the PbABCG duplicated gene pairs date to the recent whole-genome duplication that occurred 30~45 million years ago. Purifying selection has also played a critical role in the evolution of the ABCG genes. Ten PbABCG... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pear; Russet mutant; ABCG; Evolution; Gene expression. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000100137 |
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Scholtz, Gerhard; Wolff, Carsten. |
Investigations of amphipod embryonic development have a long tradition. However, many aspects of amphipod embryology are still controversial. These concern, among others, the nature of the cleavage, the origin of the germ disc, and the mode of gastrulation. On the other hand, amphipods show the same characteristic type of invariant cell division pattern in the germ band as other malacostracans. Since amphipods seem to undergo a stereotyped pattern of early cleavage they are highly interesting for our understanding of the evolution of arthropod development. In this paper, we describe the cleavage pattern of the amphipod crustacean Orchestia cavimana from the zygote to gastrulation and the formation of the germ disc using direct observation, scanning... |
Tipo: Article / Letter to the editor |
Palavras-chave: Cell lineage; Cell migration; Arthropoda; Phylogeny; Evolution. |
Ano: 2002 |
URL: http://www.repository.naturalis.nl/record/534334 |
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Hammen, L. van der. |
A comparative study is made of the three groups (Cyphophthalmi, Laniatores and Palpatores) into which Opilionida are currently subdivided. Methods, principles and terminology, adopted in this paper, correspond with those of parts I and II of the present series of studies in Chelicerata. Special attention is paid to mouthparts and appendages, to opilionid relationships, and to the evolution of chelicerate characters. It is demonstrated that Cyphophthalmi present all the essential opilionid characters, and evidently do not constitute a separate group. It is also demonstrated that Opilionida are not closely related to Actinotrichid or Anactinotrichid mites, but to other groups with a so-called myliosoma (mouthparts associated with coxisternal feeding); these... |
Tipo: Article / Letter to the editor |
Palavras-chave: Opilionida; Chelicerata; Comparative morphology; Classification; Evolution; Phy- logeny.; 42.74. |
Ano: 1985 |
URL: http://www.repository.naturalis.nl/record/317785 |
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Hammen, L. van der. |
A comparative study is made of four chelicerate classes: Apatellata (Solifugae and Pseudoscorpionida), Arachnida s. str. (both groups of Uropygi, i.e. Holopeltida and Schizomida, Amblypygi and Araneida), Scorpionida and Xiphosura. Methods, principles and terminology, adopted in this paper, correspond with those of parts I -111 of the present series of comparative studies in Chelicerata. Special attention is paid to segmentation of the body, respiratory organs, orifices of coxal glands, mouthparts, and appendages. The evolution of these structures is studied, and the relationships of the chelicerate classes and subclasses are reinvestigated and discussed. |
Tipo: Article / Letter to the editor |
Palavras-chave: Amblypygi; Apatellata; Arachnida; Araneida; Chelicerata; Evolution; Holopeltida; Morphology; Pseudoscorpionida; Schizomida; Scorpionida; Solifugae; Uropygi; Xiphosura.; 42.74. |
Ano: 1986 |
URL: http://www.repository.naturalis.nl/record/317847 |
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Tisdell, Clement A.. |
Discusses concepts of competition in economics and ecology and the relevance of evolution to both subjects. It is suggested that although speciation or increasing biodiversity tends to occur in undisturbed ecological systems, the opposite trend may occur in economic systems. Competition based on optimisation plays a significant role in theories of the evolution of species and some theories of the evolution of business or industrial structures. But evolution does not result in optimal selection of species or businesses for the future, and there is scope for doubt about what is being optimised by survivors in the evolutionary process. Ecological or biological theories of intra-specific competition involving scramble and contest competition are outlined and... |
Tipo: Working or Discussion Paper |
Palavras-chave: Biology; Competition; Evolution; Market development; Optimisation; Environmental Economics and Policy. |
Ano: 2001 |
URL: http://purl.umn.edu/48384 |
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Jacquot, Maude; Rao, Pavuluri P.; Yadav, Sarita; Nomikou, Kyriaki; Maan, Sushila; Jyothi, Y. Krishna; Reddy, Narasimha; Putty, Kalyani; Hemadri, Divakar; Singh, Karam P.; Maan, Narender Singh; Hegde, Nagendra R.; Mertens, Peter; Biek, Roman. |
For segmented viruses, rapid genomic and phenotypic changes can occur through the process of reassortment, whereby co-infecting strains exchange entire segments creating novel progeny virus genotypes. However, for many viruses with segmented genomes, this process and its effect on transmission dynamics remain poorly understood. Here, we assessed the consequences of reassortment for selection on viral diversity through time using bluetongue virus (BTV), a segmented arbovirus that is the causative agent of a major disease of ruminants. We analysed ninety-two BTV genomes isolated across four decades from India, where BTV diversity, and thus opportunities for reassortment, are among the highest in the world. Our results point to frequent reassortment and... |
Tipo: Text |
Palavras-chave: Bluetongue virus; Evolution; Reassortment; India; Selection. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00667/77882/80042.pdf |
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Alfonso Molina,C; Vilchez,Susana. |
Kin selection could provide an explanation for social behavior in bacteria. The production of public goods such as extracellular molecules is metabolically costly for bacteria but could help them to exploit nutrients or invade a host. Some bacterial cells called social cheaters do not produce public goods; however, they take advantage of these extracellular molecules. In this review, the relationships between social behavior, cooperation, and evolution of bacterial pathogenicity are analyzed. This paper also examines the role of horizontal transfer of genes encoding for virulence factors and how the movement of mobile genetic elements would influence the pathogenicity and social relationships. Moreover, the link between ecological relationships and... |
Tipo: Journal article |
Palavras-chave: Cooperation; Evolution; Pathogenicity; Public goods. |
Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2014000100013 |
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Diogo,Rui. |
As noted Gould in his recent and last book «The structure of evolutionary theory», discourses on the high importance and frequency of evolutionary trends have consumed a great part of the research on the history of clades. Although aware that natural selection theoretically yields adaptation to immediate environments, many authors defend such trends as generalised improvements somehow conferring advantages across most or all experienced environments. The high importance given to evolutionary trends is questioned by Gould, who considers that such a high importance given to such evolutionary trends bears no necessary relationship to the relative frequency or casual weight of these events in evolution, but mainly to a major bias: trends tell histories, and... |
Tipo: Journal article |
Palavras-chave: Evolution; Morphology; Phylogeny; Siluriformes; Teleostei. |
Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022006000500016 |
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Martinez,Emanuel Ricardo Monteiro; Zawadzki,Claudio Henrique; Foresti,Fausto; Oliveira,Claudio. |
In this work, we analyzed the karyotypes of five species. Hypostomus cf. heraldoi, from the Mogi-Guaçu River, had 2n = 72 chromosomes, with a nucleolar organizer region (NOR) in one chromosomal pair. Hypostomus regani, from the Mogi-Guaçu River had 2n = 72 chromosomes with NORs in two chromosomal pairs. Hypostomus sp., from the Mogi-Guaçu River basin, had 2n = 68 chromosomes, with NORs in two chromosomal pairs. Hypostomus aff. agna, from Cavalo Stream, had 2n = 74 chromosomes with NORs in two chromosomal pairs. Hypostomus cf. topavae, from Carrapato Stream, had 2n = 80 chromosomes, with NORs in two chromosomal pairs. Hypostomus species showed marked diversity in the karyotypic formula, which suggested the occurrence of several Robertsonian rearrangements... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomes; Evolution; Hypostominae; Neotropical fish; NOR. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000400006 |
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Ferreira,Amilton; Mesa,Alejo. |
The karyotypes of five species of Brazilian Pseudophyllinae belonging to four tribes were here studied. The data available in the literature altogether with those obtained with species in here studied allowed us to infer that 2n(♂)=35 is the highest chromosome number found in the family Tettigoniidae and that it is present in species belonging to Pseudophyllinae, Zaprochilinae and in one species of Tettigoniinae. In spite of that all five species exhibit secondary karyotypes arisen surely by a mechanism of chromosomal rearrangement of centric fusion, tandem fusion and centric inversion types from those with 2n(♂)=35 and FN=35, they share some common traits. The X chromosome is submetacentric (FN=36), heteropicnotic during the first prophase, the largest of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomal rearrangement; Fusion and centric inversion; Evolution. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2010000400019 |
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Ferreira,Amilton; Mesa,Alejo. |
The thirteen species of Phaneropterinae here studied can be arranged in four different groups according to their basic karyological traits. All of them share the same kind of chromosomal sex determining mechanism with X0(male) and XX(female). The X chromosome differs among species and always appears heteropycnotic during prophase I, it is the largest in the set and segregates precociously during anaphase I. Among the species, the karyotypes varies in fundamental number between 31 to 21. The meaning of these significant changes in the karyotypes in relation to the phylogeny within some large taxonomic group of species is discussed. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Chromosome; Evolution. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2007000400003 |
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CARSON,HAMPTON L.. |
This is a personal essay commemorating Brncic as a keen naturalist/evolutionist in the best Darwinian sense. His innate curiosity, so important in a scientist, led him to the discovery of cenain unique drosophilid flies in Chile. The life cycle of one species of flower-fly (Drosophila flavopilosa) is of special interest. Females oviposit in fresh flowers of a solanaceous plant that is widespread in Chilean valleys. Twenty years of combined ecological and genetic work, carried out on this species, pioneers the use of a highly specialized Drosophila species in the study of population genetics and evolution. Many eco-genetic features are revealed that are important supplements to observations made on the widely-studied generalist species of the genus |
Tipo: Journal article |
Palavras-chave: Flower-breeding Drosophila; Genetic specialization; Ecology; Population genetics; Evolution. |
Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000000008 |
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Registros recuperados: 176 | |
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