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| Author(s): |
Luísa Novara Monclar Gonçalves
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) |
| Defense date: | 2017-08-24 |
| Examining board members: |
Alexandre Adalardo de Oliveira;
Flora Souza Bacelar;
Renato Mendes Coutinho;
Diogo Meyer
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| Advisor: | Alexandre Adalardo de Oliveira; Paulo Inácio de Knegt López de Prado |
| Abstract | |
Disturbance events impact life strategy diversity in communities and life strategy evolution in populations. In the field of Ecology, disturbance occurrence is studied while an environmental factor that alters resource availability and populations abundance, causing competitive exclusion of less favorable life strategies depending on disturbance frequency and intensity. In the field of Evolutionary Biology, disturbance is evaluated as a pressure, depending on its spatial and temporal regularity, that determines the intensity of species\' evolutionary response and, as a consequence, the adaptation towards the fittest life strategy. Although there is a separation between these two fields of knowledge, ecological dynamics influence evolutionary dynamics and the other way around. Studies that mix Ecology and Evolution are becoming more common, but few or none of them takes disturbance in consideration. Here, we use an individual-based model to generate contexts in which adaptation and competitive exclusion might act apart and together in order to understand how disturbance determines life strategies that occur in communities under ecological, evolutionary and eco-evolutionary dynamics. In the model, life strategy is an inheritable character defined for a trade-off between longevity and fecundity. Simulations from the evolutionary context were composed by one population under mutation acting, simulations from the ecological context by various species without mutation and simulations from the eco-evolutionary context by various species with mutation occurrence. We observed that disturbance was positively correlated with fecund individuals preponderance in all contexts but that disturbance effect on life strategy diversity varied between the different contexts. In the evolutionary and the eco-evolutionary contexts, life strategy diversity increased with disturbance raise, while in the ecological context diversity decreased. This result evidences the mutation role as a source of new life strategy variants when there is a high renovation of individuals given by raised mortality. Only in the eco-evolutionary context there was an interspecific heterogeneity peak on intermediate levels of disturbance. In this scenario, species reproductive isolation, in contrast to populations panmixy, allows species to differ in relation to its life strategies. In parallel to this, the constant input of new life strategy variants by mutation prevents the definite extinction of life strategies from the system. Therefore, when disturbance level is intermediate, productive species as well as long-lived ones are able to coexist. Given that the different contexts resulted in varied patterns of life strategies\' relative frequency, this study evidences the importance of studying disturbance effect on communities structure and dynamics unifying processes that are typically separated between Ecology and Evolution fields (AU) | |
| FAPESP's process: | 14/27349-6 - Trade-off and life strategy selection: computer simulations of neutral dynamic and disturbances |
| Grantee: | Luísa Novara Monclar Gonçalves |
| Support Opportunities: | Scholarships in Brazil - Master |