Acúmulo de mutações em linhagens assexuadas: uma abordagem via experimentos computacionais / Accumulation of mutations in asexual lineages: a study using computer experiments

AUTOR(ES)
DATA DE PUBLICAÇÃO

2004

RESUMO

Studies about evolution have been developed since Charles Darwins publications about the Origin of species and Natural Selection in 1859. During the XX century major developments were achieved through mathematical and computational modeling, since only few number of species that their evolution can be studied in vivo, once that the time scale involed for data acquisition procedure is considerable, and for this reason the computational approach become an important tool in this study. In this thesis are presented the basic concepts to understand the process of evolution in a population as mutation, selection and adaptive landscapes, in addition some numerical results about the evolution of an asexual population using the process known as Mullers ratchet, that can be characterized by the stochastic loss of the most fitted class of individuals through mutations that are acquired in their lineages. During this work several dynamics were studied, likewise the populations under serial bottleneck passages, where we observed that the velocity of the ratchet never stops for high epistatic coefficients, while in population whose size can varies (increasing or decreasing exponentially) the ratchet halts during populations increasing until these individuals do not reach the maximum number permitted, and after this point this population behaves like the traditional infinite genome size model. At last, we show the results of populations that can interact between themselves in a predator-prey dynamics, where the behaviour of the ratchet can be understood in the previous dynamics. Another problem that was studied in this thesis is related with several topology measures of genealogical trees in order to verify the selection in a population evolution. Despite branchs length of the trees changed due to the selection, we could see that the statistical tests used do not be sufficient to infer the effect of selection under real populations.

ASSUNTO(S)

assexuados computer experiments evolução evolution catraca de muller asexual experimentos computacionais muller s ratchet

ACESSO AO ARTIGO

Documentos Relacionados