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Tony D. Williams, Professor, EBERG
BSc Exeter University; PhD Bristol University
Contact Info
Research GroupsResearch Interests
1. Physiological adaptations for breeding in birds
Over 70 years ago, Fisher highlighted the importance of an understanding of physiological mechanism to life-history theory, a point subsequently repeated by many evolutionary biologists. Despite this frequent recognition the physiological basis of most, if not all, trade-offs remains unknown. The development of the field of "evolutionary physiology" and more recently "evolutionary endocrinology" has lead to significant, and very productive, integration of physiology and evolutionary biology, although much of this work has focused on performance-related traits (e.g. sprint speed, maximum sustainable metabolic rate), rather than life-history traits. Much of the work in my lab is aimed at integration of physiology with evolutionary biology to understand mechanisms underlying variation in key LH traits (egg/offspring size and number) and trade-offs between these traits, such as that between egg size and clutch size, or the "cost of reproduction": the trade-off between current reproduction and future fecundity and/or survival. We Hormonally-mediated maternal effects: through correlative studies and experimental manipulations we have been investigating the role of non-androgens, especially estradiol and corticosterone, in mediating maternal effects via transfer of maternal hormones to yolk, and subsequent effects on offspring phenotype. For example, work by Love at al. (2005) has suggested that maternal stress hormones such as corticosterone provide a mechanistic link between maternal quality and sex-biased maternal investment in offspring. In relation to estradiol, the primary female reproductive hormone, we are investigating whether negative pleiotropic effects of this hormone required for egg production include anemia - which is commonly associated with reproduction - and if this provides a potential physiological mechanism for "cost of reproduction" (Williams et al. 2004).
Costs of egg production in song sparrows: Zanette et al. (2006 Ecology) reported a strong negative
2. Physiology of migration
Since arriving at SFU I have been involved in a range of studies of physiological mechanisms involved in long-distance migration in Arctic-nesting shorebirds, focusing on the western sandpiper (Calidris mauri).
3. NSERC/CWS Chair in Wildlife Ecology: Applied Physiology CWE web site
The mandate of the NSERC/Environment Canada Chair in Wildlife Ecology (CWE) is to foster high-quality graduate level research in wildlife ecology with specializations in behavioral, population, and physiological ecology. The central concept is to provide an interface between the mission-orientated research and management policies of the Environment Canada and the more basic-science approach of the Universities. My contribution to the Chair's mandate has been based on the belief that a rigorous understanding of the mechanisms underlying intraspecific variability in physiological traits is essential in determining, and hopefully predicting, the ability of individuals, populations and species to respond to environmental change. Specifically I have an on-going interest in the effects of pesticides and other xenobiotics on avian reproduction, in collaboration with Dr. John Elliott, Environment Canada.
PublicationsTony D. Williams publications |
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