6 de setembro de 2009

Condicionalismos genéticos da evolução

Resumo da conferência que o Doutor Henrique Teotónio apresentará no Congresso sobre o Impacto de Darwin

Reevaluating the Origin of Species: the genetic constraints of evolution

The lack of an explanation for the heredity of phenotype transmission across generations provided the main impetus for empirical research in evolutionary theory after Darwin’s “Origin of Species”. In particular, the observation of reversions at the individual (atavisms) and population (regression to the mean) levels was problematic until Mendelian genetics was formalized. After this period, theory was developed to incorporate the relative roles of natural selection, migration and mutation to change of phenotypes with either a one or two loci genetic basis, or an effectively infinite number of them. With the finding that heredity is mostly coded in DNA sequences, and with the technological ability to survey variation at these sequences in large number of individuals and populations, the need to develop models of phenotype evolution with a significant but limited number of causal loci is now obvious. To a large extent, the relative role of recombination to the origin and maintenance of phenotype diversity is poorly understood. I will discuss some of these historical developments in evolutionary genetics, as well as prospects for future research.