How do animals adapt to changing environments?
Dr Elizabeth Duncan (SoB), Dr Steve Sait (SoB)Contact email: email@example.com
How do animals respond to new or changing environments? Why is it that some species can adapt or move, while others face extinction?
Animals live in increasingly variable environments where conditions can change rapidly. In cases where environmental change is predictable, such as seasonal changes in temperature and precipitation, animals are adapted to cope with this variation. However, unpredictable and abrupt changes in the environment can have profound effects on species, increasing extinction risk for at-risk species that fail to adapt or move. Understanding how and why some animals become adapted to rapid changes in the environment and some don’t is a key question in ecology, evolution and conservation biology, particularly in light of global climate change and the increasing frequency of extreme weather events. Whilst there is ample evidence that individual species have adapted to recent environmental change, of particular concern is how trophic interactions, such as host-parasitoid interactions, will respond. This is because trophic interactions underpin food web structure and are key for ecosystem functioning and ecosystem services.
In this project we will examine the short and long-term effects of environmental variations (e.g. temperature) that mimic climate change on a well-established trophic system, the Indian meal moth (Plodia interpunctella) and the parasitic wasp (Venturia cansecens) [e.g. 1]
Insects are the most abundant and species rich group of animals on the planet. They have important roles in all terrestrial and many aquatic ecosystems and a critical for ecological functions including pollination and pest control.. Ambient temperature is particularly important for ectotherms such as insects and many insect species are potentially highly vulnerable to the impacts of climate change and have a high risk of extinction. Model systems, such as Plodia, have been used for decades to answer questions in ecology and evolution that are extremely difficult to address in the field.
Recent work in the Sait lab has shown that different frequencies of variation cause phenotypic changes over short time scales in these species, affecting population dynamics of the host and parasitoid. The response of species to different frequencies of environmental variation will depend on the extent to which it coincides with the life cycle of the organism, whether it is an adult or juvenile, and which traits are affected. This makes some species more vulnerable to extinction for a given type of environmental change than others. However, little is known about the molecular and/or genetic mechanisms underpinning these responses . Using this system we will combine measures of host and parasitoid life history traits with molecular methods [e.g. 2, 3, 4] to understand how the host and parasitoids adapt to changing environments over both short and long-time periods.
Adapation may take advantage of exisiting genetic diversity within the population. Higher levels of genetic diversity provide more variation in phenotypes, some of which may be better adapted to the new or fluctuating environmental conditions. But we now know that variation in ecologically relevant traits can occur through epigenetic mechanisms, such as DNA methylation, in the absence of genetic variation. These epigenetic marks don’t alter the DNA sequence permanently, and the effects may be transient, lasting for a single generation, or remarkably may be passed between generations. In this project we will also test the hypothesis that environmental information passed between generations facilitates adaptation to new environments.
This project will be based in the School of Biology at the University of Leeds and combines the skills of both supervisors to amalgamate ecological studies with population studies of genetic variation. In the context of the current biodiversity crisis, slowing, and ideally halting biodiversity loss is of paramount importance. A key aspect of this is identifying factors that predict resilience of species to environmental perturbation. This project will begin to address how species adapt to short- and long-term environmental change, and whether these mechanisms can act as predictors for adaptability to global change in other species.
1) Sait, et al., (2000), Nature. 405(6785): p. 448-50.
2) Duncan, et al., (2014), J Exp Zool B Mol Dev Evol. 322(4): p. 208-20.
3) Schield, et al., (2016), Methods in Ecology and Evolution. 7(1): p. 60-69.
4) Davey, et al., (2010), Brief Funct Genomics. 9(5-6): p. 416-23.
Related undergraduate subjects: