Department of Biology
B.S. University of Toronto 2001
M.S. Arkansas State University 2004
Ph.D. Arizona State University 2010
Office: Bush Science Center, room 312B
Phone: (407) 646-2452
- Animal Physiology
- Biology Journal Club
The Endocrine Basis of Food Security
Food security is a term we use to describe both the availability of food and the ability of an individual to access food. Food insecurity activates stress physiology which can impact health, and can also induce aggressive conflict between individuals trying to access to limited resources. Food abundance is also a primary determinant of many aspects of animal biology, including life-history transitions. Such transitions are largely mediated by the neuroendocrine system which responds to environmental cues and effects physiological and behavioral adjustments aimed at maximizing fitness. However the biological mechanisms that link perceptions of food security, energy balance, and individual responses (e.g., physiological, behaviors) are poorly understood.
The goals of my research program are to:
(1) characterize the neuroendocrine mechanisms (e.g. the interactions between steroids and neuropeptides) that integrate energetic information with behavioral responses
(2) Investigate how natural or human-induced fluctuations in food alter the neuroendocrine signals that synchronize life-history with food abundance;
(3) Understand how physiological and behavioral responses to food availability have influenced the evolution of life-history traits.
This novel research integrates a reductionist perspective with a broader understanding of the organism in the context of its environment, and provides a physiological basis for a topic of increasing social importance.
- Fokidis HB, NH Prior, & KK Soma. Food restriction induces social instability and alters steroid concentrations in brain regions associated with aggression. Endocrinology (in review)
- Fokidis HB, MB de Roziers, R Sparr, C Rogowski, K Sweazea, & P Deviche. 2012. The stress of variable food availability induces metabolic change independent of food intake in non-migratory songbird. Journal of Experimental Biology 215:2920-2930
- Heimovics SA, HB Fokidis, & KK Soma. 2012. Chapter 11: Brain aromatase and territorial aggression across the seasons in male song sparrows; in Brain Aromatase, Estrogens, and Behavior. Editor: J Balthazart & GF Ball. Oxford University Press.
- Deviche P, PJ Sharp, A Dawson, J Sabo, HB Fokidis, S Davies, & L Hurley. 2012. Up to the challenge? Hormonal and behavioral responses of free- ranging male Cassin’s Sparrows, Peucaea cassinii, to simulated territorial intrusion. Hormones and Behavior 61:741-749
- Fokidis HB, & P Deviche. 2012. Brain arginine vasotocin (AVT) immunoreactivity differs between urban and desert Curve-billed Thrashers, Toxostoma curvirostre: relationships with territoriality and stress physiology. Brain, Behavior, and Evolution 79:84-97.
- Fokidis HB, L Hurley, C Rogowski, K Sweazea, & P Deviche. 2011. Captivity and body condition correlates of plasma corticosterone and metabolites and of locomotor activity in a male passerine. Physiological and Biochemical Zoology 84:595-606.
- Fokidis HB, & P Deviche. 2011. Plasma corticosterone of city and desert Curve- billed Thrashers, Toxostoma curvirostre, in response to stress-related peptide administration. Comparative Biochemistry and Physiology Part A: Molecular and Integrative Physiology 159: 32-38.
- Schrey AW, M Grispo, M Awad, MB Cook, ED McCoy, HR Mushinsky, T Albayrak, S Bensch, LK Butler, HB Fokidis, H Jensen, T Imboma, AM Reynolds, MM Rios, LM Romero, IRK Stewart, H Westerdahl, DF Westneat, P Zehtindjiev, & LB Martin. 2011. Broad-scale latitudinal patterns of genetic diversity among native European and introduced house sparrow (Passer domesticus) populations. Molecular Ecology 20:1133-1143.
- Fokidis HB, M Orchinik, & P Deviche. 2011. Context-specific territorial behavior in urban birds: No evidence for involvement of testosterone or corticosterone. Hormones and Behavior 59: 133-143.
- Deviche P, L Hurley, & HB Fokidis. 2010. Avian testicular structure, function, and regulation; in Hormones and Reproduction of Vertebrates, Vol. 4: Birds. Editor: D Norris. Elsevier Inc.
- Deviche P, L Hurley, HB Fokidis, B Lerbour, B Silverin, B Silverin, J Sabo, & PJ Sharp. 2010. Acute stress rapidly decreases plasma testosterone but not luteinizing hormone in a free-ranging male songbird: Potential site of action and mechanism. General and Comparative Endocrinology 169: 82-90.
- Fokidis HB, M Orchinik, & P Deviche. 2009. Corticosterone and corticosterone binding globulin in birds: Relation to urbanization in a desert city. General and Comparative Endocrinology 160: 259-270.
- French SS, HB Fokidis, & MC Moore. 2008. Variation in stress and innate immunity in the tree lizard (Urosaurus ornatus) across an urban-rural gradient. Journal of Comparative Physiology B 178: 997-1005.