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‣ The Origin at 150: is a new evolutionary synthesis in sight?

Koonin, Eugene V.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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The 200th anniversary of Darwin and the 150th jubilee of the Origin of Species prompt a new look at evolutionary biology. The 1959 Origin centennial was marked by the consolidation of the Modern Synthesis. The edifice of the Modern Synthesis has crumbled, apparently, beyond repair. The hallmark of the Darwinian discourse of 2009 is the plurality of evolutionary processes and patterns. Nevertheless, glimpses of a new synthesis might be discernible in emerging universals of evolution.

‣ The extended evolutionary synthesis and the role of soft inheritance in evolution

Dickins, Thomas E.; Rahman, Qazi
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
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In recent years, a number of researchers have advocated extending the modern synthesis in evolutionary biology. One of the core arguments made in favour of an extension comes from work on soft inheritance systems, including transgenerational epigenetic effects, cultural transmission and niche construction. In this study, we outline this claim and then take issue with it. We argue that the focus on soft inheritance has led to a conflation of proximate and ultimate causation, which has in turn obscured key questions about biological organization and calibration across the life span to maximize average lifetime inclusive fitness. We illustrate this by presenting hypotheses that we believe incorporate the core phenomena of soft inheritance and will aid in understanding them.

‣ Towards a postmodern synthesis of evolutionary biology

Koonin, Eugene V.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
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In 2009, we are celebrating the 200th anniversary of Charles Darwin and the 150th jubilee of his masterpiece, the Origin of Species. Darwin developed the first coherent and compelling narrative of biological evolution and thus founded evolutionary biology—and modern biology in general, remembering the famous dictum of Dobzhansky. It is, however, counter-productive, and ultimately, a disservice to Darwin’s legacy, to define modern evolutionary biology as neo-Darwinism. The current picture of evolution, informed, in particular, by results of comparative genomics and systems biology, is by far more complex than that presented in the Origin of Species, so that Darwinian principles, including natural selection, are incorporated into the evolving new synthesis as important but certainly not all-embracing tenets. This expansion of evolutionary biology does not denigrate Darwin in the least but rather emphasizes the fertility of his ideas.

‣ Evolutionary Developmental Biology and Human Language Evolution: Constraints on Adaptation

Fitch, W. Tecumseh
Fonte: Springer US Publicador: Springer US
Tipo: Artigo de Revista Científica
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A tension has long existed between those biologists who emphasize the importance of adaptation by natural selection and those who highlight the role of phylogenetic and developmental constraints on organismal form and function. This contrast has been particularly noticeable in recent debates concerning the evolution of human language. Darwin himself acknowledged the existence and importance of both of these, and a long line of biologists have followed him in seeing, in the concept of “descent with modification”, a framework naturally able to incorporate both adaptation and constraint. Today, the integrated perspective of modern evolutionary developmental biology (“evo-devo”) allows a more subtle and pluralistic approach to these traditional questions, and has provided several examples where the traditional notion of “constraint” can be cashed out in specific, mechanistic terms. This integrated viewpoint is particularly relevant to the evolution of the multiple mechanisms underlying human language, because of the short time available for novel aspects of these mechanisms to evolve and be optimized. Comparative data indicate that many cognitive aspects of human language predate humans, suggesting that pre-adaptation and exaptation have played important roles in language evolution. Thus...

‣ Energy, genes and evolution: introduction to an evolutionary synthesis

Lane, Nick; Martin, William F.; Raven, John A.; Allen, John F.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
Publicado em 19/07/2013 Português
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Life is the harnessing of chemical energy in such a way that the energy-harnessing device makes a copy of itself. No energy, no evolution. The ‘modern synthesis’ of the past century explained evolution in terms of genes, but this is only part of the story. While the mechanisms of natural selection are correct, and increasingly well understood, they do little to explain the actual trajectories taken by life on Earth. From a cosmic perspective—what is the probability of life elsewhere in the Universe, and what are its probable traits?—a gene-based view of evolution says almost nothing. Irresistible geological and environmental changes affected eukaryotes and prokaryotes in very different ways, ones that do not relate to specific genes or niches. Questions such as the early emergence of life, the morphological and genomic constraints on prokaryotes, the singular origin of eukaryotes, and the unique and perplexing traits shared by all eukaryotes but not found in any prokaryote, are instead illuminated by bioenergetics. If nothing in biology makes sense except in the light of evolution, nothing in evolution makes sense except in the light of energetics. This Special Issue of Philosophical Transactions examines the interplay between energy transduction and genome function in the major transitions of evolution...

‣ A Mechanistic Explanation Linking Adaptive Mutation, Niche Change, and Fitness Advantage for the Wrinkly Spreader

Spiers, Andrew J.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
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Experimental evolution studies have investigated adaptive radiation in static liquid microcosms using the environmental bacterium Pseudomonas fluorescens SBW25. In evolving populations a novel adaptive mutant known as the Wrinkly Spreader arises within days having significant fitness advantage over the ancestral strain. A molecular investigation of the Wrinkly Spreader has provided a mechanistic explanation linking mutation with fitness improvement through the production of a cellulose-based biofilm at the air-liquid interface. Colonisation of this niche provides greater access to oxygen, allowing faster growth than that possible for non-biofilm—forming competitors located in the lower anoxic region of the microcosm. Cellulose is probably normally used for attachment to plant and soil aggregate surfaces and to provide protection in dehydrating conditions. However, the evolutionary innovation of the Wrinkly Spreader in static microcosms is the use of cellulose as the matrix of a robust biofilm, and is achieved through mutations that deregulate multiple diguanylate cyclases leading to the over-production of cyclic-di-GMP and the stimulation of cellulose expression. The mechanistic explanation of the Wrinkly Spreader success is an exemplar of the modern evolutionary synthesis...

‣ Current perspectives and the future of domestication studies

Larson, Greger; Piperno, Dolores R.; Allaby, Robin G.; Purugganan, Michael D.; Andersson, Leif; Arroyo-Kalin, Manuel; Barton, Loukas; Climer Vigueira, Cynthia; Denham, Tim; Dobney, Keith; Doust, Andrew N.; Gepts, Paul; Gilbert, M. Thomas P.; Gremillion, K
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
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It is difficult to overstate the cultural and biological impacts that the domestication of plants and animals has had on our species. Fundamental questions regarding where, when, and how many times domestication took place have been of primary interest within a wide range of academic disciplines. Within the last two decades, the advent of new archaeological and genetic techniques has revolutionized our understanding of the pattern and process of domestication and agricultural origins that led to our modern way of life. In the spring of 2011, 25 scholars with a central interest in domestication representing the fields of genetics, archaeobotany, zooarchaeology, geoarchaeology, and archaeology met at the National Evolutionary Synthesis Center to discuss recent domestication research progress and identify challenges for the future. In this introduction to the resulting Special Feature, we present the state of the art in the field by discussing what is known about the spatial and temporal patterns of domestication, and controversies surrounding the speed, intentionality, and evolutionary aspects of the domestication process. We then highlight three key challenges for future research. We conclude by arguing that although recent progress has been impressive...

‣ The genome as a developmental organ

Lamm, Ehud
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Português
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This paper applies the conceptual toolkit of Evolutionary Developmental Biology (evo-devo) to the evolution of the genome and the role of the genome in organism development. This challenges both the Modern Evolutionary Synthesis, the dominant view in evolutionary theory for much of the 20th century, and the typically unreflective analysis of heredity by evo-devo. First, the history of the marginalization of applying system-thinking to the genome is described. Next, the suggested framework is presented. Finally, its application to the evolution of genome modularity, the evolution of induced mutations, the junk DNA versus ENCODE debate, the role of drift in genome evolution, and the relationship between genome dynamics and symbiosis with microorganisms are briefly discussed.

‣ Form and function remixed: developmental physiology in the evolution of vertebrate body plans

Newman, Stuart A
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
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The most widely accepted model of evolutionary change, the Modern Evolutionary Synthesis, is based on the gradualism of Darwin and Wallace. They, in turn, developed their ideas in the context of 19th century concepts of how matter, including the tissues of animals and plants, could be reshaped and repatterned. A new physics of condensed, chemically, electrically and mechanically excitable materials formulated in the 20th century was, however, readily taken up by physiologists, who applied it to the understanding of dynamical, external condition-dependent and homeostatic properties of individual organisms. Nerve conduction, vascular and airway dynamics, and propagation of electrical excitations in heart and brain tissue all benefited from theories of biochemical oscillation, fluid dynamics, reaction–diffusion-based pattern instability and allied dissipative processes. When, in the late 20th century, the development of body and organ form was increasingly seen to involve dynamical, frequently non-linear processes similar to those that had become standard in physiology, a strong challenge to the evolutionary synthesis emerged. In particular, large-scale changes in organismal form now had a scientific basis other than gradualistic natural selection based on adaptive advantage. Moreover...

‣ The role of internal and external constructive processes in evolution

Laland, Kevin; Odling-Smee, John; Turner, Scott
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
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The architects of the Modern Synthesis viewed development as an unfolding of a form already latent in the genes. However, developing organisms play a far more active, constructive role in both their own development and their evolution than the Modern Synthesis proclaims. Here we outline what is meant by constructive processes in development and evolution, emphasizing how constructive development is a shared feature of many of the research developments central to the developing Extended Evolutionary Synthesis. Our article draws out the parallels between constructive physiological processes expressed internally and in the external environment (niche construction), showing how in each case they play important and not fully recognized evolutionary roles by modifying and biasing natural selection.

‣ Life is physics: evolution as a collective phenomenon far from equilibrium

Goldenfeld, Nigel; Woese, Carl
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/11/2010 Português
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Evolution is the fundamental physical process that gives rise to biological phenomena. Yet it is widely treated as a subset of population genetics, and thus its scope is artificially limited. As a result, the key issues of how rapidly evolution occurs, and its coupling to ecology have not been satisfactorily addressed and formulated. The lack of widespread appreciation for, and understanding of, the evolutionary process has arguably retarded the development of biology as a science, with disastrous consequences for its applications to medicine, ecology and the global environment. This review focuses on evolution as a problem in non-equilibrium statistical mechanics, where the key dynamical modes are collective, as evidenced by the plethora of mobile genetic elements whose role in shaping evolution has been revealed by modern genomic surveys. We discuss how condensed matter physics concepts might provide a useful perspective in evolutionary biology, the conceptual failings of the modern evolutionary synthesis, the open-ended growth of complexity, and the quintessentially self-referential nature of evolutionary dynamics.; Comment: To appear in Annual Reviews of Condensed Matter Physics (2011)

‣ Testing spectral models for stellar populations with star clusters: II. Results

Delgado, Rosa M. Gonzalez; Fernandes, Roberto Cid
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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High spectral resolution evolutionary synthesis models have become a routinely used ingredient in extragalactic work, and as such deserve thorough testing. Star clusters are ideal laboratories for such tests. This paper applies the spectral fitting methodology outlined in Paper I to a sample of clusters, mainly from the Magellanic Clouds and spanning a wide range in age and metallicity, fitting their integrated light spectra with a suite of modern evolutionary synthesis models for single stellar population. The combinations of model plus spectral library employed in this investigation are Galaxev/STELIB, Vazdekis/MILES, SED@/GRANADA, and Galaxev/MILES+GRANADA, which provide a representative sample of models currently available for spectral fitting work. A series of empirical tests are performed with these models, comparing the quality of the spectral fits and the values of age, metallicity and extinction obtained with each of them. A comparison is also made between the properties derived from these spectral fits and literature data on these nearby, well studied clusters. These comparisons are done with the general goal of providing useful feedback for model makers, as well as guidance to the users of such models. We find that new generation of models using the GRANADA and MILES libraries are superior to STELIB-based models both in terms of spectral fit quality and regarding the accuracy with which age and metallicity are retrieved. Accuracies of about 0.1 dex in age and 0.3 dex in metallicity can be achieved as long as the models are not extrapolated beyond their expected range of validity.; Comment: accepted to MNRAS

‣ The extended evolutionary synthesis: Its structure, assumptions and predictions

Laland, Kevin; Uller, Tobias; Feldman, Marcus W.; Sterelny, Kim; Mu¨ller, Gerd B.; Moczek, Armin; Jablonka, Eva; Odling-Smee, John
Fonte: Royal Society of London Publicador: Royal Society of London
Tipo: Artigo de Revista Científica
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Scientific activities take place within the structured sets of ideas and assumptions that define a field and its practices. The conceptual framework of evolutionary biology emerged with the Modern Synthesis in the early twentieth century and has since expanded into a highly successful research program to explore the processes of diversification and adaptation. Nonetheless, the ability of that framework satisfactorily to accommodate the rapid advances in developmental biology, genomics and ecology has been questioned. We review some of these arguments, focusing on literatures (evo-devo, developmental plasticity, inclusive inheritance and niche construction) whose implications for evolution can be interpreted in two ways-one that preserves the internal structure of contemporary evolutionary theory and one that points towards an alternative conceptual framework. The latter, which we label the 'extended evolutionary synthesis' (EES), retains the fundaments of evolutionary theory, but differs in its emphasis on the role of constructive processes in development and evolution, and reciprocal portrayals of causation. In the EES, developmental processes, operating through developmental bias, inclusive inheritance and niche construction, share responsibility for the direction and rate of evolution...

‣ Extending the Modern Synthesis: The evolution of ecosystems

Rodrick Wallace
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
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The Modern Evolutionary Synthesis formalizes the role of variation, heredity, differential reproduction and mutation in population genetics. Here we explore a mathematical structure, based on the asymptotic limit theorems of information theory, that instantiates the punctuated dynamic relations of organisms and their embedding environments. The mathematical overhead is considerable, and we conclude that the model must itself be extended even further to allow the possibility of the transfer of heritage information between different classes of organisms. In essence, we provide something of a formal roadmap for the modernization of the Modern Synthesis.

‣ Extending the Modern Synthesis: The evolution of ecosystems

Rodrick Wallace
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
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The Modern Evolutionary Synthesis formalizes the role of variation, heredity, differential reproduction, and mutation in population genetics. Here we explore a mathematical structure, based on the asymptotic limit theorems of communication theory, that instantiates the punctuated dynamic relations of organisms with their embedding environments, including the possibility of the transfer of heritage information between different classes of organisms. In essence, we provide something of a formal roadmap for the modernization of the Modern Synthesis, making application to both relatively rapid evolutionary punctuated equilibrium and to the conservation of ecological interactions across deep evolutionary time.

‣ Expanding the modern synthesis II: Formal perspectives on the inherent role of niche construction in fitness

Rodrick Wallace
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
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Expanding the modern synthesis requires elevating the role of interaction within and across various biological scales to the status of an evolutionary principle. One way to do this is to characterize genes, gene expression, and embedding environment as information sources linked by crosstalk, constrained by the asymptotic limit theorems of information theory (Wallace, 2010a). This produces an inherently interactive structure that escapes the straightjacket of mathematical population genetics or other replicator dynamics. Here, we examine fitness from that larger perspective, finding it intimately intertwined with niche construction. Two complementary models are explored: niche construction as mediating the connection between environmental signals and gene expression, and as a means of tuning the channel for the transmission of genetic information in a noisy environment. These are different views of the same elephant, in a sense, seen as simplified projections down from a larger dynamic system.

‣ Expanding the modern synthesis II: Formal perspectives on the inherent role of niche construction in fitness

Rodrick Wallace
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
Relevância na Pesquisa
37.848748%
Expanding the modern synthesis requires elevating the role of interaction within and across various biological scales to the status of an evolutionary principle. One way to do this is to characterize genes, gene expression, and embedding environment as information sources linked by crosstalk, constrained by the asymptotic limit theorems of information theory (Wallace, 2010a). This produces an inherently interactive structure that escapes the straightjacket of mathematical population genetics or other replicator dynamics. Here, we examine fitness from that larger perspective, finding it intimately intertwined with niche construction. Two complementary models are explored: niche construction as mediating the connection between environmental signals and gene expression, and as a means of tuning the channel for the transmission of genetic information in a noisy environment. These are different views of the same elephant, in a sense, seen as simplified projections down from a larger dynamic system.

‣ Um exame histórico-filosófico da biologia evolutiva do desenvolvimento

Almeida, Ana Maria Rocha de; El-Hani, Charbel Niño
Fonte: Universidade de São Paulo. Faculdade de Filosofia, Letras e Ciências Humanas Publicador: Universidade de São Paulo. Faculdade de Filosofia, Letras e Ciências Humanas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/03/2010 Português
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O desenvolvimento tem papel central na compreensão da evolução dos organismos multicelulares, dado que é o processo que resulta na produção da forma orgânica adulta. Logo, toda inovação morfológica deve ser também o resultado de modificações no desenvolvimento. Entretanto, a biologia do desenvolvimento permaneceu à margem da síntese evolutiva e o desenvolvimento foi tratado por muito tempo como uma caixa preta entre o genótipo e o fenótipo. Somente a partir dos anos 1980, foi dada mais atenção ao papel do desenvolvimento na evolução, resultando daí avanços teóricos e empíricos inesperados. Tais avanços resultaram na emergência de um novo campo de investigação, a biologia evolutiva do desenvolvimento (evo-devo), que vem cumprindo papel importante na construção de uma nova compreensão da evolução das formas orgânicas. Argumentamos que este campo tem papel central em uma "nova síntese evolutiva", atualmente em construção, que está comprometida com um "pluralismo de processos", ou seja, com a ideia de que não somente a seleção natural, mas também diversos outros mecanismos têm papel causal e explicativo na evolução biológica. A partir da discussão de algumas dicotomias clássicas no pensamento evolutivo...

‣ Por que o desenvolvimento ontogenético foi tratado como uma “caixa preta” na síntese moderna da evolução?; Por que o desenvolvimento ontogenético foi tratado como uma “caixa preta” na síntese moderna da evolução?

Araújo, Leonardo Augusto Luvison; Universidade Federal do Rio Grande do Sul.; de Araújo, Aldo Mellender; Universidade Federal do Rio Grande do Sul - UFRGS.
Fonte: Federal University of Santa Catarina – UFSC Publicador: Federal University of Santa Catarina – UFSC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 30/08/2015 Português
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http://dx.doi.org/10.5007/1808-1711.2015v19n2p263The Modern Evolutionary Synthesis relegated the ontogenetic development to a “black box”. In this article, we argue that the absence of ontogenetic development in the Evolutionary Synthesis was due its strong foundation in transmission genetics. We discuss three research strategies of transmission genetics that created an incompatibility with the ontogenetic development: (i) particulate inheritance model; (ii) population as locus for genetics research; (iii) and experimental tools that have been applied to remove “non-heritable fluctuations” from ontogenetic and environmental effects. These practices have contributed to the strength of the genetic inheritance, but also excluded the ontogenetic development from the explanation of heredity and evolution. This distinction has been perpetuated in the Evolutionary Synthesis.; http://dx.doi.org/10.5007/1808-1711.2015v19n2p263A Síntese Moderna da Evolução tratou o desenvolvimento ontogenético como uma “caixa preta”. Neste artigo pretendemos defender que a ausência do desenvolvimento ontogenético na Síntese Moderna se deveu, em grande medida, à forte fundação dessa disciplina na genética da transmissão. São discutidas três estratégias de pesquisa da genética da transmissão que estiveram diretamente envolvidas com a omissão do desenvolvimento ontogenético na Síntese Moderna: (i) o modelo de herança de partículas; (ii) a população como locus de pesquisa; (iii) e a adoção de ferramentas experimentais que procuraram remover “flutuações não hereditárias” de origem ambiental e ontogenética. Essas práticas contribuíram para a solidez da herança genética...

‣ Systematics and evolutionary biology: uneasy bedfellows?

Schwartz,Jeffrey H.
Fonte: Instituto de Biología Publicador: Instituto de Biología
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2011 Português
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The history of systematics and evolutionary biology demonstrates how greatly the "modern evolutionary synthesis" instrumentally prevented, rather than facilitated, the intellectual growth and maturity of the diversity of evolutionary disciplines. In truth, the claim of the synthesis being synthetic is essentially without basis, indeed a myth. Instead, the "synthesis" had precisely the opposite effect: namely, squelching the arena of debate, disagreement, and diverse theorizing that had characterized the preceding decades. Although each of the 3 primary architects of the synthesis - Dobzhansky, Mayr, and Simpson - had his own agenda, they were united around the theme of population genetics and population thinking. When applied to systematics, especially by Mayr, the result can now be seen as confused at best. Perhaps this review will provoke a revival of earlier years of intellectual curiosity and fervor, and rekindle interest in systematic method and theory.