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Registros recuperados: 383 | |
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Niccolo Caldararo; Michael Guthrie. |
The recently published Altai fossil sequence from Denisova Cave was purported to be so different from anatomically modern humans, yet have the physiological landmarks of that species designation. When the published sequence was examined it was found that segments in the mtDNA hypervariable regions could be found to align with that of anatomically modern humans if one introduced an insertion at a position found in Neanderthals. Some other points of interest arise from a reconsideration of the sequences for other published samples and Neanderthals from the same perspective. |
Tipo: Manuscript |
Palavras-chave: Genetics & Genomics; Evolutionary Biology. |
Ano: 2011 |
URL: http://precedings.nature.com/documents/5360/version/2 |
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Neeraja M. Krishnan; Basuthkar J. Rao. |
Messenger RNA secondary structure prevents mutations at functionally important sites. Mutations at exposed sites would cause micro-adaptations, niche-specialization, and therefore, can be thought to promote K-strategists. Exposing, rather than protecting, conserved sites, is also potentially adaptive because they probably promote macro-adaptive changes. This presumably fits r-strategists: their population dynamics tolerate decreased survival. We found that helix-forming tendencies are greater at evolutionary conserved sites of plant mitochondrial mRNAs than at evolutionary variable sites in a majority (73%) of species–gene combinations. K-strategists preferentially protect conserved sites in short genes, r-strategists protect them most in larger... |
Tipo: Manuscript |
Palavras-chave: Bioinformatics; Plant Biology; Evolutionary Biology. |
Ano: 2008 |
URL: http://precedings.nature.com/documents/1922/version/1 |
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Rodrick Wallace. |
The 'self-referential' character of evolutionary process noted by Goldenfeld and Woese (2010) can be restated in the context of a generalized Darwinian theory applied to economic process through a 'language' model: The underlying inherited and learned culture of the firm, the short-time cognitive response of the firm to patterns of threat and opportunity that is sculpted by that culture, and the embedding socioeconomic environment, are represented as interacting information sources constrained by the asymptotic limit theorems of information theory. If unregulated, the larger, compound, source that characterizes high probability evolutionary paths of this composite then becomes, literally, a self-dynamic language that... |
Tipo: Manuscript |
Palavras-chave: Ecology; Bioinformatics; Earth & Environment; Evolutionary Biology. |
Ano: 2011 |
URL: http://precedings.nature.com/documents/5650/version/1 |
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Steven P. Brady. |
The network of roads on the landscape is vast, and has wide-reaching ecological influence. Recent investigations have focused on understanding impacts of contaminants from road runoff, especially deicing agents such as road salt. Despite growing research concerning ecological impacts of roads, our understanding of long-term consequences remains nascent. This stems in part from a dearth of investigations, and in part because ecological research typically ignores evolution on contemporary timescales. Yet reports of evolution influencing ecological outcomes are growing, suggesting this influence may be the rule rather than the exception. This may be especially true for species with spatially structured populations. For amphibians, such structuring coupled... |
Tipo: Presentation |
Palavras-chave: Ecology; Earth & Environment; Evolutionary Biology. |
Ano: 2009 |
URL: http://precedings.nature.com/documents/3674/version/1 |
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Tracy Packiam Alloway; Ross Alloway. |
The growth and decline of fluid intelligence is associated with brain structural changes. For example, development of fluid IQ is associated with cortex thickness during the critical period between 6 to 12 years old. On the other end of the lifespan, poor performance in cognitive functioning is attributed to a decrease of frontal gray matter density in elderly populations. In particular, there is a sharp decline in fluid IQ scores after 65 years of age. There is substantial evidence that working memory and fluid intelligence (Gf) share neural substrates, such as the prefrontal and parietal cortices. However, very little research has examined whether the pattern of growth and decline in working memory mirrors that of fluid intelligence. For example, does... |
Tipo: Manuscript |
Palavras-chave: Evolutionary Biology. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4655/version/1 |
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Mark Conyers. |
Standard texts dutifully list 16 essential elements for plant growth, yet the literature indicates that the boundary between essential and nonessential nutrients for plants is not always clear. When animals and 'lower' organisms are considered, the team of 16 is considerably expanded and the notion of essentiality is blurred. Why are some elements more important than others to plants and to organisms in general? Here I propose three criteria by which elements might have been selected in the development of organisms: low atomic weight, at least modest abundance, and ease of assembly into complex structures. Assembly of the structural elements C, N, S, P, and O is based on valency and ionic potential. The selection of monovalent elements... |
Tipo: Manuscript |
Palavras-chave: Earth & Environment; Evolutionary Biology. |
Ano: 2009 |
URL: http://precedings.nature.com/documents/3223/version/1 |
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Steven J. Wagstaff; Ilse Breitwieser; Christopher Quinn; Motomi Ito. |
Biogeographic relationships in the southern hemisphere have puzzled biologists for the last two centuries. Once joined to form the supercontinent Gondwana, Africa, Antarctica, Australia, New Zealand and South America are widely separated by the Pacific and Indian oceans. Sir Joseph Hooker was the first to suggest that Antarctica served as a corridor for plant migration not unlike the land-bridges in the northern hemisphere. While the Antarctic flora was largely erased by glaciation during the Pleistocene, at least some of these Antarctic plant communities found refuge on the subantarctic islands. Here we provide support for the hypothesis that giant herbs persisted in the subantactic islands prior to the onset of Pleistocene glaciation, then dispersed... |
Tipo: Manuscript |
Palavras-chave: Ecology; Plant Biology; Evolutionary Biology. |
Ano: 2007 |
URL: http://precedings.nature.com/documents/1272/version/1 |
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Erik D. Andrulis. |
Life is an inordinately complex unsolved puzzle. Despite significant theoretical progress, experimental anomalies, paradoxes, and enigmas have revealed paradigmatic limitations. Thus, the advancement of scientific understanding requires new models that resolve fundamental problems. Here, I present a theoretical framework that economically fits evidence accumulated from examinations of life. This theory is based upon a straightforward and non-mathematical core model and proposes unique yet empirically consistent explanations for major phenomena including, but not limited to quantum gravity, phase transitions of water, why living systems are predominantly CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur), homochirality of sugars and... |
Tipo: Poster |
Palavras-chave: Evolutionary Biology. |
Ano: 2012 |
URL: http://precedings.nature.com/documents/7050/version/1 |
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Qin Zhu; Geoffrey Bingham. |
Heaviness perception involves a misperception of weight known, since the 19th century, as the Size-Weight Illusion ^1^. The larger of two objects of equal mass is reported to be lighter than the smaller when they are lifted. The illusion has been found to be reliable and robust. It persists even when people know that the masses are equal and handle objects properly ^2^. It has been exhibited by children of only 2 years of age ^3,4^. All this suggests that the effect might be intrinsic to humans. Although different hypotheses have been advanced to account for the illusion over the 100+ years it has been studied ^5-11^, its origin remains unknown. More recently, people's perception of optimal objects for long distance throwing was found to exhibit a... |
Tipo: Manuscript |
Palavras-chave: Developmental Biology; Ecology; Evolutionary Biology. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4584/version/1 |
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T. Michael Keesey. |
A phyloreference is a statement indicating a taxon within a phylogenetic context. A common use for phyloreferences is in phylogenetic definitions, which tie taxonomic names to taxa via such statements. Several conventions for writing phyloreferences have been proposed, but most only cover a few “standard” forms (node‑, branch‑, and perhaps apomorphy‑based clades) without the capacity to represent more “exotic” forms (e.g., ancestor‑based clades and qualified/modified references). In order to build a complete phyloreferencing language, the mathematical underpinnings of phylogenetic contexts must be clarified. A phylogenetic context may be modeled as a directed, acyclic... |
Tipo: Presentation |
Palavras-chave: Bioinformatics; Evolutionary Biology. |
Ano: 2011 |
URL: http://precedings.nature.com/documents/4652/version/2 |
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C Jaco Klok; Jon Harrison. |
Recent geological models indicate a marked increase in atmospheric oxygen partial pressure (aPO~2~) to 32 kPa in the Permo-Carboniferous (approx. 300 million years ago), subsequently falling to 13 kPa in the Triassic^1^.These aPO~2~ changes have been hypothesized to cause multiple major evolutionary events^2^ including the appearance and subsequent extinction of giant insects and other taxa^3, 4^. Patterns of increasing tracheal investment in larger insects support this hypothesis^5^, as do observations of positive relationships between aPO~2~ and body size in single- or multi-generational experiments with _Drosophila melanogaster_ and other insects^6^. Large species likely result from many generations of selection for large body size driven by predation,... |
Tipo: Manuscript |
Palavras-chave: Ecology; Evolutionary Biology. |
Ano: 2008 |
URL: http://precedings.nature.com/documents/1831/version/1 |
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Roberto Gatti Cazzolla. |
For a long time ecologists have questioned the variations of biodiversity across the latitudinal gradient. Recently it has emerged that the changes in [beta]-diversity are caused simply by changes in the sizes of species pools. I combined the species pool size and the fractal nature of ecosystems to clarify some general patterns of this gradient. Considering temperature, humidity and NPP as the main variables of an ecosystem niche and as the axis of the polygon in the Cartesian plane, it is possible to build fractal hypervolumes, whose the fractal dimension rises up to three, moving towards the equator. It follows that the best figure that graphically synthesizes the evolutionary forces that fit this ecosystem hypervolume is the fractal cauliflower. |
Tipo: Manuscript |
Palavras-chave: Ecology; Evolutionary Biology. |
Ano: 2012 |
URL: http://precedings.nature.com/documents/6917/version/1 |
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Qipeng Zhang; Ming Lu; Qinghua Cui. |
MicroRNAs are one class of important gene regulators at the post-transcriptional level by binding to the 3’UTRs of target mRNAs. It has been reported that human microRNAs are evolutionary conserved and show lower single nucleotide polymorphisms (SNPs) than their flanking regions. However, in this study, we report that the human-specific microRNAs show a higher SNP density than both the conserved microRNAs and other control regions, suggesting rapid evolution and positive selection has occurred in these regions. Furthermore, we observe that the human-specific microRNAs show greater SNPs minor allele frequency and the SNPs in the human-specific microRNAs show fewer effects on the stability of the microRNA secondary structure, indicating that the... |
Tipo: Manuscript |
Palavras-chave: Genetics & Genomics; Bioinformatics; Evolutionary Biology. |
Ano: 2008 |
URL: http://precedings.nature.com/documents/2127/version/1 |
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Jason W. J. W. W. Whitaker; Ryan R. S. Setten; Ulv U. A. Ankerstjerne. |
Research shows that women‘s preferences for masculine voices (low pitch) vary as a function of the menstrual cycle, becoming positively augmented around ovulation. The proximate cause catalyzing this effect is attributed to fluctuating estrogen levels. Thus, the introduction of hormonally based birth control has been to shown to have a dampening effect in experiments researching women‘s preference of dimorphic secondary sexual characteristics. However, this dampening effect has not yet been explored in respect to women‘s preferences for masculine voice types. This experiment sought, first, to investigate the effect of birth control on subjects off and on birth control; and, second, to replicate past findings:... |
Tipo: Poster |
Palavras-chave: Evolutionary Biology. |
Ano: 2011 |
URL: http://precedings.nature.com/documents/5895/version/1 |
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Registros recuperados: 383 | |
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