Biosciences Seminar Speaker 14 March 2019

Biosciences Seminar Series - Winter 2019
14 March 2019 - 1pm - Zoology Museum

Eco-evolutionary dynamics in a host-parasitoid system exposed to environmental fluctuations

Dr Marianne Mugabo

(University of Leeds, UK)

photo by Glen Marangelo

Our Biosciences Seminar Series continues with a talk by our guest from Leeds, Dr Marianne Mugabo from the School of Biology at the University of Leeds. Marianne is an evolutionary ecologist broadly interested in understanding the drivers of multi-trophic eco-evolutionary dynamics and on the mechanisms and consequences of transgenerational effects on life history variation.

Abstract

Climate change is one of the primary drivers of the current biodiversity crisis. Species and community responses to mean changes in climate variables have received much attention in recent years. However, the impact of changes in the frequency of spatio-temporal variation in climate variables on species and interactions between species is still poorly understood. In this context, we investigated the effects of different types of temporal environmental fluctuations (none, red (positively correlated) noise, blue (negatively correlated) noise and white (purely random) noise) on the eco-evolutionary dynamics of the host-parasitoid system comprised of the Indian meal moth, Plodia interpunctella, and its parasitoid wasp, Venturia canescens. We combined single generation life history assays with a multi-generation microcosm experiment during which host and parasitoid abundances were monitored weekly and individual traits (e.g., body size, host fecundity, rate of parasitism) were measured repeatedly in ‘host-alone’ and ‘host-parasitoid’ populations subjected to different frequencies of temperature fluctuations. At the individual level, our results show that species and traits differ in their responses to the colour of temperature fluctuations, with stronger responses in hosts than parasitoids. Surprisingly, however, parasitoid populations were more affected by environmental fluctuations than host populations. These results highlight the complexity of the mechanisms through which environmental fluctuations affect top-down and bottom-up regulations in trophic interactions.

Hope to see many of you - everyone most welcome to attend!


For the list of forthcoming seminars see here