My research covers a number of different topics, answering large-scale questions in ecology and evolution through the use of model systems:
Biological responses to global change
My primary interests lie in the biological impacts of (i) climate change and (ii) urbanisation. My work investigates changing geographical (distributions) and temporal (phenology) patterns of species occurrence using historical datasets. It is vital to evaluate the capacity of different species to respond to environmental change, as those species that cannot respond face an uncertain future. Principally I have used insects (Odonata, Hymenoptera, and Syrphidae) as well as mammals as model systems for investigating these topics.
- Hassall, C. (2015) Odonata as candidate macroecological barometers for global climate change, Freshwater Science, 34 (3): 1040-1049.
- Hassall, C., Keat, S., Thompson, D.J., and Watts, P.C. (2014) Bergmann’s rule is maintained during a rapid range expansion in a damselfly, Global Change Biology, 20: 475–482.
- Hassall, C., Thompson, D.J., French, G.C. and Harvey, I.F. (2007) Historical changes in the phenology of British Odonata are related to climate. Global Change Biology, 13, 933-941.
Freshwater ecology and conservation
Freshwater comprises only a very small proportion of all the water on earth but is vital to the functioning of terrestrial ecosystems. My research focuses on the ecology of ponds (lentic water bodies with an area <2ha), which dominate many landscapes and contribute an enormous amount of biodiversity to the regional species pool. Despite their great number and importance, these small habitats are relatively poorly understood both in terms of what drives their biodiversity and how that diversity changes over time. One interesting aspect of ponds is their use to provide ecosystem services (flood control, pollution reduction, aesthetics) in urban areas. My research focuses on how these services can be maintained or enhanced while also maximising the contribution of urban ponds to urban biodiversity.
- Hassall, C. and Anderson, S. (2015) Stormwater ponds can contain comparable biodiversity to unmanaged wetlands in urban areas. Hydrobiologia, 745: 137-149.
- Hassall, C. (2014) The ecology and biodiversity of urban ponds, WIREs Water, 1: 187–206.
- Hassall, C., Hollinshead, J. and Hull, A. (2012) Temporal dynamics of aquatic communities and implications for pond conservation, Biodiversity and Conservation, 21 (3): 829-852.
Evolution of insects
Alongside my ecological research, I am involved in work on a number of evolutionary topics. It has often been said that wild animals (and insects in particular) do not live long enough to experience aging in the wild. I have been involved in work that has demonstrated that wild damselfly populations do show aging in the wild. I am also involved in work on the evolution of mimicry, using the hoverflies (Diptera: Syrphidae) that mimic stinging bees and wasps (Hymenoptera) as a model system. Finally, I am interested in the ways that form and function interact with the environment in the case of insect flight.
- Hassall, C., Sherratt, T. N., Watts, P. C., Thompson, D. J. (2015), Live fast, die old: no evidence of reproductive senescence or costs of mating in a damselfly (Odonata: Zygoptera). Journal of Animal Ecology, 84: 1542–1554.
- Penney, H.D., Hassall, C., Skevington, J.H., Abbott, K.R. and Sherratt, T.N. (2012) A comparative analysis of the evolution of imperfect mimicry. Nature, 483: 461-464.
- Thompson, D.J., Hassall, C., Lowe, C.D. and Watts, P.C. (2011) Field estimates of reproductive success in a model insect: behavioural surrogates are poor predictors of fitness, Ecology Letters, 14: 905-913.
Application of technology to teaching
As well as scientific research, I maintain a funded program of research on pedagogical advances in “blended learning” – the application of technology to complement face-to-face teaching. Particular areas of interest include identifying and breaking down barriers to the use of technology, and testing the effectiveness of teaching interventions.
My work involves collaborations across the University of Leeds, where I am based in the Ecology and Evolution Research Group. I am also an active member of Water@Leeds – a research hub containing 150 researchers focusing on all aspects of water research. I maintain collaborations with the Institute of Psychological Sciences, where I work with psychologists to use humans as model systems to investigate evolutionary questions. Finally, I collaborate extensively with staff in the School of Geography to answer landscape scale environmental questions concerning the ecology of freshwaters.
Ecology and Evolution of Mimicry in a Changing World (Funder: EU)
My current research focus involves testing fundamental hypotheses concerning how and when some organisms evolve to mimic other organisms, and (more interestingly) when mimicry is imperfect. The work involves studies of the degree of mimetic similarity shown by harmless, Batesian mimics (with a focus on hover flies, Diptera: Syrphidae) to the harmful animals that they resemble in terms of both morphological and behavioural mimicry, quantified using a variety of approaches. These projects integrate my interests in the evolution and the ecology of these systems, to build a picture of how ecological processes (such as the responses of mimics and models to climate change) may influence eco-evolutionary interactions.
Thermal microclimates in aquatic ecosystems (Funder: Royal Society)
The importance of microclimates has been recognized in terrestrial systems, but there has been little study of aquatic microclimates. However, understanding how temperature varies at small scales in freshwater systems is essential to understanding ecosystem function and the diversity of aquatic organisms. There are also important implications for the distribution of semi-aquatic disease vectors, which require certain thermal thresholds for development. This project uses a drone to image freshwater landscapes in order to test for the effects on macroinvertebrate community structure and function. While my past work has focused on large scale patterns in phenological and distributional change, this new project is testing hypotheses at the centimeter scale.
Electronic Resources in Physiology Education (Funder: Physiological Society)
The shift in emphasis from lecturers as the “sage on the stage” to the “guide at the side” has led to the development of substantial online resources to support novel pedagogical techniques. However, the use of these resources is hindered by a series of barriers: teachers may not be aware of the resources, may not have the knowledge to use them, or may not be able to identify opportunities to use them. This project focuses on quantifying these 1st, 2nd, and 3rd order barriers to the use of online resources in physiology education, and identifying solutions that can enhance physiology education.
Social Media in Higher Education (Funder: University of Leeds)
Social media offer a valuable opportunity to provide a network for students and teachers, both within and outside of the classroom. However, there are often different degrees of comfort with these tools and staff may be completely unfamiliar with many newer platforms. Furthermore, students may be unwilling to share what they see as a “private” space with their university lecturers. This project is designed to evaluate the attitudes of staff and students to different social media in order to produce a toolkit that is both pedagogically appropriate and has the support of both learners and educators.
I am extremely grateful to a wide array funders for financial support:
- Natural Environment Research Council
- EU Marie Curie Fellowship
- British Ecological Society
- Government of Canada
- Ontario Ministry of Research and Innovation
- Freshwater Biological Association
- Physiological Society
- Royal Entomological Society
- Carleton University
- University of Leeds