917 resultados para Swahili-speaking peoples


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The genetic history of a group of populations is usually analyzed by reconstructing a tree of their origins. Reliability of the reconstruction depends on the validity of the hypothesis that genetic differentiation of the populations is mostly due to population fissions followed by independent evolution. If necessary, adjustment for major population admixtures can be made. Dating the fissions requires comparisons with paleoanthropological and paleontological dates, which are few and uncertain. A method of absolute genetic dating recently introduced uses mutation rates as molecular clocks; it was applied to human evolution using microsatellites, which have a sufficiently high mutation rate. Results are comparable with those of other methods and agree with a recent expansion of modern humans from Africa. An alternative method of analysis, useful when there is adequate geographic coverage of regions, is the geographic study of frequencies of alleles or haplotypes. As in the case of trees, it is necessary to summarize data from many loci for conclusions to be acceptable. Results must be independent from the loci used. Multivariate analyses like principal components or multidimensional scaling reveal a number of hidden patterns and evaluate their relative importance. Most patterns found in the analysis of human living populations are likely to be consequences of demographic expansions, determined by technological developments affecting food availability, transportation, or military power. During such expansions, both genes and languages are spread to potentially vast areas. In principle, this tends to create a correlation between the respective evolutionary trees. The correlation is usually positive and often remarkably high. It can be decreased or hidden by phenomena of language replacement and also of gene replacement, usually partial, due to gene flow.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Este trabajo presenta la experiencia docente de una Red multidisciplinar de investigadores (Red I+Do+i), en la que han participado profesorado y estudiantes. El objetivo principal de la experiencia docente “Speaking Library” es tiene una doble vertiente. Por un lado, generar documentos de trabajo especializados en investigación en docencia y en materias curriculares relevantes para el alumnado, así como en soportes más accesibles, atractivos y útiles para la comunidad educativa. Se ha tenido especial interés en los estudiantes con Necesidades Específicas de Apoyo Educativo (NEAE) y en este sentido la creación de materiales ha sido fundamentalmente audiovisual. Por otro lado, la gestión dichos materiales a través de repositorios universitarios (Universidad de Alicante y Universidad Miguel Hernández) y de un canal docente de YouTube (canal IDOi), para su ulterior difusión nacional e internacional a las distintas bases de datos y portales adecuados (OCW, blogs UA, VUALA, Blogs externos, etc.) que facilitarán su consulta. Los resultados y reflexiones finales presentan varios documentos convertidos a un formato amigable, visual y valioso para los estudiantes con NEAE, a la vez que se ha diseñado un protocolo de actuación para la elaboración de los mismos y creado un canal docente en YouTube.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador: