EVOL HET ENV · Sex and the maintenance of diversity in heterogeneous habitats
FP6 — Marie Curie Actions (Human Resources and Mobility)
- Duration
- 2006-10-01 → 2007-09-30
- EU contribution
- €40,000
- Participants
- 1
- Scheme
- ERG
Lines connect the coordinator with its partners.
Results in brief
Final Activity Report Summary - EVOL HET ENV (Sex and the maintenance of diversity in heterogeneous habitats)
The evolution of drug resistance is a key issue of both fundamental and applied importance. Most organisms have evolved resistance for nearly all pesticides used. Despite major breakthroughs achieved with studies on natural populations, some avenues of research remain unexplored due to a lack of a suitable system amenable to experimental manipulation at the ecological and evolutionary timescale. With this project, we aimed at contributing to the current knowledge on this topic by tackling the process of pesticide resistance using the model organism Caenorhabditis elegans and levamisole, a widely used nematicide for which the mechanism of action and the genetic basis of resistance are known. By creating lines of experimental evolution subjected to levamisole or to a control environment, we aimed at testing whether an outcrossed population of C. elegans adapted to levamisole within a short timescale. In addition, we measured whether adaptation entailed a cost in performance in the ancestral environment. Finally, we assessed the consequences of such adaptation to the susceptibility to another widely used pesticide, Ivermectin. Since the two nematicides operate on either the inhibitory or the excitatory neural networks, a strong trade-off in adaptation to the two pesticides is expected. That is, nematodes may develop resistance to one of the pesticides, but this is expected to entail an increase in susceptibility to the other pesticide. We found that populations exposed to Levamisole developed resistance at a very fast rate. Indeed, survival of C. elegans exposed to levamisole was near to 100 % within 20 generations and their fecundity increased relative to control populations. In addition, this resistance did not entail a cost in the ancestral environment or in Ivermectin. These results suggest that pesticide resistance is indeed a threat to natural populations
Data: CORDIS, © European Union
Project objective
An understanding of the mechanisms that generate and maintain biodiversity is fundamental in current biological research, both from a fundamental and an applied viewpoint. In this project, we address how the interplay between environmental heterogeneity and breeding system variation affect diversity at multiple levels of biological organization. Using the model organism Caenorabditis elegans and the powerful tool of experimental evolution, we propose to test hypotheses concerning the maintenance of polymorphisms in environments where resources are spatially heterogenous.Specifically, we will investigate:(1) whether adaptation to different resources entails fitness trade-offs;(2) how density regulation at different levels affect the maintenance of genetic diversity and(3) whether the occurrence of an out-crossing mode of reproduction hampers the maintenance of polymorphisms due to recombination among locally-adapted populations.Moreover, we aim at tackling the genetics underlying the process, using the molecular biology technology available for studying this organism. We will follow the evolution of replicate populations during fifty generations for characters related to fitness and also gene diversity at the molecular level. Predominantly selfing and exclusively out-crossing populations of C. elegans are already established at the host institution. This project comes as a follow-up of the research carried out by the candidate during her post-doctoral studies, and matches perfectly with the research of the host institution as well as with its long-term aims. We expect that the results from this project will contribute decisively to evolutionary theory epical verification. The fellow will take this opportunity to return to her country of origin and set paths for an independent research career in Portugal.
Original text from CORDIS.
Participants
- FUNDAÇÃO CALOUSTE GULBENKIAN · LISBOACoordinatorPortugal
Links
Data: CORDIS, © European Union