Meeting Abstract

S4.1-4  Sunday, Jan. 5 09:30  Addition of relative metabolism in the “pace of life” hypothesis: incorporating ectothermic physiology SANDMEIER, F.C.*; TRACY, C.R.; Lindenwood University – Belleville; University of Nevada, Reno FSandmeier@lindenwood.edu

Incorporating metabolic rate as an additional axis in a theoretical model of the interspecific relationship between “pace-of-life” and the strength of an adaptive immune response (Lee 2006) makes the model more universally applicable. Using reptiles as an example, we hypothesize that animals with slow metabolic rates will invest more in innate versus adaptive immunity. This pattern logically derives from the concept that constant, high metabolism and body temperature should optimize the functioning of the adaptive (induced) immune response resulting in rapid, targeted cell division needed for T and B cell maturation and increasing the functions of antibodies via kinetics. Given the apparent importance of metabolism in the strength of adaptive immune responses, we suggest that increased immune function may have conferred a fitness advantage to ancestral vertebrates that led to the evolution of endothermy. Finally we show that general characteristics of the immune systems of host species, as shaped by both pace-of-life and metabolic rate (and body temperature), influence the ecology and evolution of host-pathogen systems in several, predictable ways.