Specialization, evolution and coexistence in a community context
|PhD ceremony:||Ms E. van Velzen|
|When:||March 02, 2015|
|Supervisor:||prof. dr. R.S. (Rampal) Etienne|
|Where:||Academy building RUG|
|Faculty:||Science and Engineering|
Ellen van Velzen studied eco-evolutionary dynamics in the context of trophic interactions in two types of systems: plant-herbivore interactions and multiparasitoid-host interactions. Her main focus was to study the effect of eco-evolutionary dynamics on the evolution and coexistence of divergent strategies in the trophic level under study (different specialization strategies in herbivores; defense strategies in plants; and parasitization strategies in parasitoids). Ecology and evolutionary biology have long been regarded as separate fields, due to the common belief that the two processes operate on different timescales and do not affect each other. As evidence for rapid evolution in nature has accumulated, recent years have seen a renewed interest in the interplay between ecology and evolution, also known as eco-evolutionary dynamics; and it has become evident that feedbacks between ecology and evolution can yield results that would not be predicted by considering either process by itself. Van Velzen found that eco-evolutionary dynamics often promoted evolutionary divergence into different strategies, but more often than not impaired stable coexistence of said strategies. Destabilization of coexistence occurs when there is a strong feedback between evolution and ecological dynamics on both trophic levels, driving large changes in ecological dynamics (e.g. fluctuations in abundance) which in turn affect selection. Stable coexistence, on the other hand, appears to be promoted when evolutionary change mostly affects competitors, and therefore ecological dynamics, on the same trophic level.