Professor Neil Metcalfe - Research Interests
Room 427, Graham Kerr Building
Institute of Biodiversity, Animal Health & Comparative Medicine
College of Medical, Veterinary & Life Sciences
University of Glasgow
Tel.: 0141 330 5968
Fax: 0141 330 5971
Google Scholar - Publications profile
Behavioural ecology, physiological ecology and life-history strategies
I am interested in the relationships between individual differences in behaviour or physiology and subsequent life-history patterns, and have investigated these mainly using experimental studies of fish populations. For instance, we found that small differences in the dominance status and competitive ability of very young salmon can have major consequences: more dominant fish grow faster, and are therefore likely to metamorphose and complete the life-cycle a year ahead of subordinate siblings. This is related to their physiology: we have shown that dominance in fry is linked to standard metabolic rate, and have been investigating this further by looking at the causes and consequences of variation in metabolic rate. In collaboration with John Armstrong of the Marine Scotland Freshwater Lab at Pitlochry we have looked at the effects of intraspecific variation in metabolic rate on digestive strategies and efficiency, and together with Ton Groothuis at the University of Groningen (Holland) have been testing whether maternal hormones influence the metabolic rate of offspring. We have also examined how variation in metabolic rate arises, how stable it is within individuals, and what are the costs and benefits of a high or low standard metabolic rate under different ecological conditions.
This work is about to be greatly extended by the recent award of a 5 year European Research Council (ERC) Advanced Grant that will explore how variation in metabolic phenotypes is maintained as a result of context-dependent selection. The project will employ two new postdocs, one research assistant and 2 technicians, and will involve experimental manipulations at every level from cells to populations.
In a separate line of research, I have been interested in exploring the role of oxidative stress in mediating life histories. In collaboration with Tom Pike, Jan Lindstrom and Jon Blount, I have been investigating how sticklebacks use carotenoids to advertise their health and viability, and how they trade off using carotenoids for signalling versus protecting against oxidative stress. I am now looking further at the role of antioxidants and oxidative stress in influencing fish life histories.
Current work is also examining the influence of maternal effects in determining offspring viability. The research is focusing on wild populations of salmon, and is testing whether variation in the early growth or current condition of adult spawning fish influences the viability of the offspring. This study is in collaboration with John Armstrong, Simon McKelvey (Cromarty Firth District Salmon Fishery Board) and Alastair Stephen (Scottish & Southern Electricity). We are also testing whether parental condition in salmon influences the pattern of telomere attrition, levels of oxidative damage and rate of senescence, in collaboration with Pat Monaghan who has a related research group examining telomere dynamics, funded by a separate ERC Advanced Grant.
Our work is carried out with fish in laboratory, natural or semi-natural conditions (e.g. using stream tanks such as at the Scottish Centre for Ecology and the Natural Environment - these allow us to observe the territorial behaviour of fish in a natural environment over which we have complete control, since we can alter water velocity and depth, food supply, fish density, bottom topography etc). We also use the extensive fish-holding facilities in the Graham Kerr Building on campus.
Effects of early growth trajectories on adult phenotypes
I am interested in the ecological factors that influence growth patterns (in particular the long-term effects of different growth trajectories). Many species of animal are capable of periods of accelerated growth (in particular after a period of poor nutrition - when conditions improve, they show 'catch up' growth and so compensate for the earlier deficit). However, there is increasing evidence that this rapid growth carries long term costs, in terms of future viability and survival. We are therefore exploring the consequences of changes in early nutrition (and hence growth rates) in a variety of species, looking both at the whole organism and at the cellular/molecular level.
Work on zebra finches (in collaboration with Pat Monaghan) has been exploring the effects of early diet quality on adult phenotype, metabolic rate, antioxidant status and rates of senescence, measured at both the cellular (e.g. telomere length) and whole organism level (e.g. flight performance).
Experiments on green swordtails and sticklebacks (in collaboration with Jan Lindström) have looked at effects of early growth rate on the behaviour of adult males and females, testing whether early nutrition affects future swimming performance, attractiveness to mates, dominance, fecundity, oxidative stress and lifespan. My group (in collaboration with Pat Monaghan) has also looked at the effect of decelerating (slow-down) growth trajectories as well as accelerating (catch-up) growth, and shown that while catch-up growth results in many and diverse costs in later life, slow-down growth is beneficial. These experiments are combined with theoretical modelling of life history decisions.