Biogeografia evolutiva: a seleção sexual e o índice de predação como fatores evolutivos do Lebistes (Poecilia reticulata) em comunidades íctias

Pós-graduação em Geografia - IGCE

Construção de estatutos de ciência para a biologia numa perspectiva histórico-filosófica: uma abordagem estruturante para seu ensino

Pós-graduação em Educação para a Ciência - FC

Herdabilidade em caracteres de crescimento de populações fragmentadas da espécie arbórea copaifera langsdorffii (fabaceae)

Pós-graduação em Agronomia - FEIS

Estimativas de herdabilidades em populações naturais contínuas e fragmentadas de araucaria angustifolia (bertol.) kuntze

Pós-graduação em Agronomia - FEIS

Genomic divergence of zebu and taurine cattle identified through high-density SNP genotyping

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Worldwide HLA-E nucleotide and haplotype variability reveals a conserved gene for coding and 3 ' untranslated regions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Sustainable worm control practices in South America

A high prevalence of nematodes, especially Haemonchus contortus and Trichostrongylus colubriformis, that exhibit multiple anthelmintics resistance has been reported in sheep in several South American countries. For this reason, the development of strategies that are less dependent on anthelmintic treatments is imperative for the prophylaxis of gastrointestinal nematode infections in small ruminants. Integrated grazing using cattle and sheep can be used for pasture decontamination with considerable reduction of H. contortus and T. colubnformis infective larvae after cattle grazing. Several breeds of sheep exhibit genetically related resistance against nematode infections, as is the case of crioulo, native or naturalised breeds of sheep. These breeds descend from livestock introduced by Portuguese and Spanish settlers and have been submitted to a long process of natural selection in various environmental conditions. In the South, the Crioula Lanada breed is more resistant to H. contortus than are Corriedale sheep. In tropical areas, where the minimum temperatures are usually higher than 20 degrees C, hair sheep flourish, especially the Santa Ines breed, which also display a higher level of resistance to nematode infections compared with certain breeds of European origin. However, Santa Ines sheep have inferior carcass quality compared with other commercial breeds. Recent studies showed that the crossbreeding of Santa Ines ewes with sires of breeds with high potential for growth and meat production, results in crossbred animals with high productivity and a satisfactory degree of resistance against nematode infections. Several studies have indicated that improvement in nutrition has a beneficial effect on the development of resistance in lambs that were naturally or artificially infected with nematodes. Therefore, supplementary feeding and breeding strategies to improve resistance to nematodes are feasible options in the effort to reduce dependence on anthelmintic drugs to control worm infections in sheep. (C) 2013 Elsevier B.V. All rights reserved.

Evolucionismo linguístico: um paralelo entre evolucionismo biológico e mudança linguística

The comparison between linguistic change and biologic evolution is a subject that has caused and still causes much controversy among linguists and other academics that see, in this parallel, problems related to similar attempts in the nineteenth century by Social Darwinism, which approached the biological evolution with social and cultural development of a people. However, this paper aims to show that today this parallel is not built in the same way as was done before. Names like William Labov, Salikoko Mufwene, Jonathan West and Hildo Honorio do Couto in linguistics; Charles Darwin in biology; and Tom Ingold and Clifford Geertz in anthropology, showed that areas of Humanities, such as linguistics and anthropology, and of Biological Sciences, as phylogeny and genetics, are likely to be worked together by the great similarities between processes that compose them. Thus, based on the writings of these authors and some others, this paper presents this theme’s controversy; it shows the similarities between characteristics of languages and species; it seeks through the concepts MA Mental, MA Social and MA Natural of the languages (coined by Couto on Linguística, ecologia e ecolinguística: contato de línguas) to develop ideas of how it is possible to think the language change in the light of Darwin's concept, Natural Selection; and finally, it shows that the parallel theme is rather productive, based on the texts and discussions presented in the whole paper, and that the controversy has been being dissolved with more and more people working on the parallel between language and species

Avaliação da autozigosidade em vacas Nelore (Bos indicus) através de genótipos SNP de alta densidade

Pós-graduação em Medicina Veterinária - FCAV

Coeffcients of herdability and relatedness in a forest fragment of Araucaria angustifolia (Bertol.) Kuntze using genetic markers

Methods based on genetic markers to estimate the coefficient of heritability in natural populations are important to understand the effects of natural selection on inheritance of quantitative traits. The objective of this study was to investigate the genetic control of the trait plant height in a fragmented population of Araucaria angustifolia. This study was conducted in a forest fragment of 5.4 ha of area, located in the State of Parana, Brazil. Estimates of heritability were performed using data from genotypes and height of regenerating individuals of the population. Four methods to estimate the relatedness between pairs of individuals (RITLAND, 1996; LYNCH; RITLAND, 1999; QUELLER; GOODNIGHT, 1989; WANG, 2002) for three distances (without criteria, 25 and 50 m) were used. The coefficient of heritability estimated using the estimator of relatedness of Ritland (1996), suggest that the genetic control of the trait height is low in the regeneration, thus the natural selection as well as the artificial selection have a low potential to change the mean of the population. The estimates based on the other methods to calculate the relatedness presented low precision, indication that these methods are not adequate for the data used.

Heritability of Growth traits in fragmented popularions of Copaifera langsdorffii Desf. (Fabaceae)

The aim of this study is to investigate the genetic control of growth traits in the initial phases of development in fragmented populations of Copaifera langsdorffii Desf., using microsatellite markers. For the effect two populations of C. langsdorffii were used: a municipal park located in Sao Jose do Rio Preto (SJRP) and at Assis Ecological Station (AES), both in the state of sao Paulo, Brazil. The model to estimate the heritability coefficient is the method of regression of a measure of phenotypic similarity and an estimate of kinship between paired individuals. The coefficients of relatedness and heritability were estimated for three classes of distance (10, 20 and 30 m) within populations. Estimates of heritability were low (maximum 0.15) for all traits, ranging from positive values for regenerating individuals of the population SJRP and from negative to positive for the juvenile population AES. In evolutionary terms, these results indicate little chance of changing the population mean of the characters studied by natural selection; with strong random environmental effects changing this average. The results also suggest that the heritability for height to decrease between regenerating to juvenile stage and the natural selection in natural populations is stronger in the early stages of plant development.

Biology Teachers'Conceptions of the Diversity of Life and the Historical Development of Evolutionary Concepts

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Body size and allometric shape variation in the molly Poecilia vivipara along a gradient of salinity and predation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Uma pesquisa didático-epistemológica na formação inicial em ciências biológicas: como a evolução forjou a grande quantidade de criaturas que habitam o nosso planeta?

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Mechanical behavior of natural fiber composites

The use of natural fibers as reinforcement in polymeric composites for technical applications has been a research subject of scientists during the last decade. There is a great interest in the application of sisal fiber as substitutes for glass fibers, motivated by potential advantages of weight saving, lower raw material price, and ecological advantages of using green resources which are renewable and biodegradable.Castor oil, a triglyceride vegetable that has hydroxyl groups, was reacted with 4,4' diphenylmethane diisocyanate (MDI) to produce the polyurethane matrix. Woven sisal fibers were used untreated and thermal treated at 60 C for 72h, and the composites were processed by compression molding.The present work study tensile behavior at four composites: dry sisal/polyurethane, humid sisal/polyurethane, dry sisal/phenolic and humid sisal/phenolic resin. The moisture content influences of sisal fibers on the mechanical behaviors were analyzed.Experimental results showed a higher tensile strength for the sisal/phenolic composites followed by sisal/polyurethane, respectively. In this research, sisal composites were also characterized by scanning electron microscopy. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of ICM11