Adaptation to extreme environmental change: Consequences of multiple stressors for species interactions and their extinction risk
The increasing rate at which climate change is occurring, and the frequency and magnitude of change, means that environments can be unpredictable, they can change abruptly, and they can be extreme. There is ample evidence that individual species have adapted to past environmental change, but understanding how they might adapt to rapid changes in the future is a key question in ecology, evolution and conservation biology because species that fail to adapt face an increasing risk of extinction. Often the focus of climate research is on temperature, but it is increasingly recognised that the interaction between different kinds of stressors may determine a species’ capacity to adapt to environmental change. Furthermore, how those adaptations play out when different species interact with each other is not well known. Of particular concern is how trophic interactions will respond to environmental change because these interactions, such as predators and their prey, are fundamental to ecological food webs, and they are critical for ecosystem functioning and ecosystem services, such as pollination and pest control.
How species respond to rapidly changing environments may depend on the molecular mechanisms underpinning these responses. Adaptation may take advantage of existing genetic diversity within the population. Higher levels of genetic diversity may provide more variation in phenotypes so that these populations are better adapted to coping with new or rapidly fluctuating environmental conditions. Alternatively, information about the environment may be passed between generations without DNA modification (epigenetics). But, whether environmental information is passed between generations and whether this facilitates adaptation to new environments is not well understood.
This project will be based in the School of Biology at the University of Leeds and combine the complementary skills of the Sait (https://biologicalsciences.leeds.ac.uk/school-of-biology/staff/132/dr-steven-sait) and Duncan (https://biologicalsciences.leeds.ac.uk/school-of-biology/staff/59/dr-elizabeth-duncan) labs to amalgamate ecological studies with population studies of genetic variation and molecular mechanisms. The project aligns with current research projects in their labs, as well as their wider networks of scientists working on climate change science.
This project will employ powerful ecological and genetic approaches to address critical gaps in knowledge. Using a well-established laboratory system (Sait et al. 2000), the effects of environmental variations that mimic future climate change scenarios can be carried out, and their impacts on an insect host-parasitoid trophic interaction examined. You can watch the fascinating interplay between the larval host, the Indian meal moth Plodia interpunctella, and the parasitoid wasp Venturia canescens here
https://www.youtube.com/watch?v=O2HVHZDv9o4
Recent work in the Sait lab has shown that different frequencies of temperature fluctuations, coupled with variation in resource availability, can cause phenotypic changes that dramatically affect host-parasitoid population dynamics (Figure 1; Mugabo et al. 2019), while humidity may act to moderate the impact of extreme temperatures (Li et al. 2024).
Figure 1: An example of a microcosm with adult parasitic wasps (V. cansecens) visible and moth (P. interpunctella) larvae present in the bottom of the box. These microcosms are a powerful way of investigating the effect of environmental change on life history adaptation in these species.
Little is known about the genetic mechanisms underpinning these responses, but this a critical missing piece of the puzzle. Using this system the project will combine measures of host and parasitoid life history traits with molecular methods to understand how the host and parasitoid adapt to changing environments within and across multiple generations.
Selected references :
1) Sait SM et al. (2000), Nature, https://doi.org/10.1038/35013045
2) Mugabo M et al. (2019) Journal of Animal Ecology, https://doi.org/10.1111/1365-2656.13069
3) Li D et al. (2024) Ecology and Evolution, http://dx.doi.org/10.1002/ece3.70047
3) Duncan, EJ et al. (2014) Journal of Experimental Zoology B (Mol. Dev. Evol.) 322, 208-20.
4) Schield DR et al. (2016) Methods in Ecology and Evolution 7, 60-69.
5) Davey JW & Baxter ML (2010) Briefings in Functional Genomics 9, 416-23.