RESUMO
The role of long-range dispersal in the coexistence of sexual and asexual relatives in a population of hermaphrodite flowering plants is investigated. In these populations, growth and reproduction often occur during a sedentary stage that is then followed by dispersal of propagules. These two stages are clearly distinguishable and show strong seasonality. A modeling approach that accurately describes this kind of dynamics of mixed populations is a system of two nonlinear integro-difference equations. It is shown that this kind of model can accommodate coexistence of the two different reproductive types.
Assuntos
Ecossistema , Modelos Biológicos , Fenômenos Fisiológicos Vegetais , Reprodução Assexuada/fisiologia , Reprodução/fisiologia , Algoritmos , Simulação por Computador , Magnoliopsida/fisiologia , Dinâmica não Linear , Desenvolvimento Vegetal , Plantas/genética , Dinâmica Populacional , Estações do AnoAssuntos
Evolução Biológica , Seleção Genética , Terminologia como Assunto , Animais , Humanos , Filogenia , PlantasRESUMO
Many criticisms have been levelled at null hypothesis significance testing (NHST). It is argued here that although there is reason to doubt that data subjected only to NHST have been subjected to sufficient analysis, the search for clear answers to well-formulated questions derived from substantive hypotheses is well served by NHST. To reliably draw inferences from data, however, NHST may need to be complemented by additional methods of analysis, such as the use of confidence intervals and of estimates of the degree of association between independent and dependent variables. It is argued that these should be seen as complements of, rather than as substitutes for, NHST since they do not directly test the strength of evidence against a null hypothesis.
Assuntos
Interpretação Estatística de Dados , Probabilidade , Intervalos de Confiança , Distribuições EstatísticasRESUMO
Most previous models of populations mixed for reproductive mode have omitted important local interactions between sexual and asexual individuals. We propose a cellular automaton model where local rules focus on fertilization and colonization. This model produces rich sets of data which are then studied by means of spatial statistics. Results point to the fixation of one of the two reproductive modes in the landscape. However, some examples of coexistence of sexual and asexual conspecifics over long periods of time are also found. This model is an example of a CA that diverges from its mean field approximation. The formation of sexual and asexual clusters reduces effective colonization rate in the CA and may account for this behaviour.