Heterochrony
Mostrando 1-12 de 12 artigos, teses e dissertações.
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1. Os Processos heterocrônicos nos vertebrados : o exemplo dos Rhynchosauria (Reptilia, Archosauromorpha) do estado do rio Grande do Sul, Brasil
Aspectos heterocrônicos encontrados na evolução do crânio dos Rhynchosauria foram estudados como uma contribuição ao melhor entendimento da evolução deste grupo, bem como dos vertebrados em geral; para o que partiu-se do material Triássico do estado Rio Grande do Sul. A Análise dos Componentes Principais incluiu 22 crânios e foi utilizada para est
Publicado em: 2009
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2. Ontogenia craniana comparada de Arctocephalus australis, Callorhinus ursinus e Otaria byronia (Otariidae: Pinnipedia)
The search for mechanisms that can generate major morphological changes has led to the study of ontogeny, in part because some kinds of modifications of ontogenies seem an excelent way to generate major phenotypic change. We focus here on Arctocephlaus australis, Callorhinus ursinus and Otaria byronia with the aim of contributing to the understanding of the
Publicado em: 2009
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3. The effectiveness and the heterochrony of basketball players adaptation responses submitted to a different structuring load training models and competition / A eficacia e a heterocronia das respostas de adaptação de basquetebolistas submetidos a diferentes modelos de estruturação da carga de treinamento e competição
o presente estudo buscou investigar o efeito de três diferentes modelos de estruturação da carga de treinamento e competição em basquetebolistas. A amostra foi composta por 32 atletas, adultos, do sexo masculino, da divisão principal (AI), que foram divididos em três grupos (Modelos) com média e desvio padrão para idade de: Modelo de cargas seletiva
Publicado em: 2006
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4. Allometric scaling and heterochrony in Mesosaurids (Amniota, Sauropsida) from the Irati Formation (Permian of the Paraná Basin, Brazil)
Anais da Academia Brasileira de Ciências. Publicado em: 2002-06
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5. The analysis of ontogenetic trajectories: When a change in size or shape is not heterochrony
Heterochrony has become a central organizing concept relating development and evolution. Unfortunately, the standard definition of heterochrony—evolutionary change in the rate or timing of developmental processes—is so broad as to apply to any case of phenotypic evolution. Conversely, the standard classes of heterochrony only accurately describe a small
The National Academy of Sciences of the USA.
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6. Intraspecific heterochrony and life history evolution: Decoupling somatic and sexual development in a facultatively paedomorphic salamander
Morphological features such as size and shape are the most common focus in studies of heterochronic change. Frequently, these easily observed and measured features are treated as a major target of selection, potentially ignoring traits more closely related to fitness. We question the primacy of morphological data in studies of heterochrony, and instead sugge
The National Academy of Sciences.
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7. Treatment with 2,4-dinitrophenol mimics ontogenetic and phylogenetic changes in a hydractiniid hydroid.
Clonal plants, fungi, and invertebrate animals often display both intra- and interspecific heterochronic variation in the relative proportions of ramets (e.g., polyps, plantlets) and stolons (or rhizomes, hyphae). Treatment of developing colonies of Podocoryne carnea, a hydractiniid hydroid, with dilute solutions of 2,4-dinitrophenol (DNP), an uncoupler of o
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8. Inducible morphology, heterochrony, and size hierarchies in a colonial invertebrate monoculture.
Conditional or inducible strategies are a powerful tool for analyzing the evolution of aggressive behavior. Structures such as stolons and nematocyst-laden tentacles, induced to deter encroachment by competitors, are proportionately better represented in clonal and colonial marine invertebrates than in aclonal animals. Stolons can be produced by colonies of
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9. Heterochrony and patterns of cranial suture closure in hystricognath rodents
Sutures, joints that allow one bone to articulate with another through intervening fibrous connective tissue, serve as major sites of bone expansion during postnatal craniofacial growth in the vertebrate skull and represent an aspect of cranial ontogeny which may exhibit functional and phylogenetic correlates. Suture evolution among hystricognath rodents, an
Blackwell Science Inc.
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10. Molecular heterochrony in the early development of Drosophila
Heterochrony, the relative change of developmental timing, is one of the major modes of macroevolutionary change; it identifies temporally disassociated units of developmental evolution. Here, we report the results of a fine-scale temporal study for the expression of the developmental gene hairy and morphological development in three species of Drosophila, D
The National Academy of Sciences.
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11. Trophic molecules and evolution of the nervous system.
Although recent work has reemphasized the general importance of ontogeny in evolution, underlying developmental molecular mechanisms are largely undefined. What heritable ontogenetic mechanisms result in the evolution of new morphologies and functions? Such questions are particularly difficult in the nervous system, in which each of 10(11) neurons forms appr
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12. Early lineage specification of long-lived germline precursors in the colonial ascidian Botryllus schlosseri
In many taxa, germline precursors segregate from somatic lineages during embryonic development and are irreversibly committed to gametogenesis. However, in animals that can propagate asexually, germline precursors can originate in adults. Botryllus schlosseri is a colonial ascidian that grows by asexual reproduction, and on a weekly basis regenerates all
Company of Biologists.