Doctor Lisa Bromfield
Candidature
Graduated PhD 2019
Thesis Title
Individual Strategies to Cope with Environmental Change: A test of the pace-of-life syndrome hypothesis
Research Project
The pace-of-life syndrome (POLS) hypothesis is an important and potentially game-changing hypothesis in ecology. It suggests that variation in single traits (i.e. metabolic rate) cannot be understood in isolation because suites of behavioural, physiological and life-history traits have co-evolved as integrated syndromes that optimise an individual's fitness depending on their intrinsic condition and environmental conditions.
This hypothesis provides a compelling argument for shifting our research paradigm away from its current focus on mean values of single traits for a population or species and towards an integrative study of individual variation in correlated suites of behavioural, physiological and life-history traits.
Co-variation of traits provides an explanation for the perplexing variation in behavioural and physiological traits that seem likely to be under strong directional selection. Metabolic rate, for example, often varies several-fold even among individuals of the same population.
Yet, such variation could be explained if it represents one component of a correlated suite of traits, including behavioural (e.g. boldness, activity, social status), physiological (energetics, stress response) and life-history (survival, growth and reproductive rate), which provide an individual with increased fitness under specific conditions. Moreover, the existence of individual diversity in the form of syndromes or alternate strategies is thought to be important for population stability during times of environmental variability.
Despite its theoretical appeal, research is needed to test the assumptions underlying the POLS hypothesis:
- consistent differences in trait values among individuals (or populations)
- correlations among traits across environment contexts, and
- differential fitness consequences of contrasting pace-of-life syndromes.
My current experimental research project aims to provide a robust test of the POLS hypothesis in a wild population of house mice (Mus musculus).
This will help answer a fundamental question in physiological ecology and increase our understanding of the ecological significance of variation in key behavioural, physiological and life-history traits.
Publications
Facey SL, Fidler DB, Rowe RC, Bromfield LM, Nooten SS, Staley JT, Ellsworth DS, Johnson SN, (2017) 'Atmospheric change causes declines in woodland arthropods and impacts specific trophic groups', Agricultural and Forest Entomology, vol.19, no.1, pp 101-112
Ryalls JMW, Moore B, Riegler M, Bromfield LM, Hall AAG, Johnson SN, (2017) 'Climate and atmospheric change impacts on sap-feeding herbivores: a mechanistic explanation based on functional groups of primary metabolites', Functional Ecology, vol.31, no.1, pp 161-171
Supervisors
Dr Christopher Turbill, Dr Paul Rymer and Dr Peter Biro (Deakin University)
