Meeting Abstract

7.3  Tuesday, Jan. 4  Could helminths drive geographic patterns in vertebrate eco-immunology? ADELMAN, J.S.*; MUñOZ, S.A.; Princeton University and the Max Planck Institute for Ornithology; Princeton University jsadelma@princeton.edu

Two nonexclusive hypotheses currently dominate research into the selective and mechanistic drivers of variation in vertebrate immune defenses: 1) costly immune responses must be traded-off with other life history traits and 2) higher pathogen exposure, at an evolutionary timescale, selects for higher immune responsiveness. We argue that a third nonexclusive hypothesis should be added to this list: current infection status drives the observed differences in immunological defense. In particular, infection with helminth worms can suppress many of the immune responses currently measured in eco-immunology. Here we present data from song sparrows (Melospiza melodia) showing negative correlations between worm burden and inflammatory immune responses, including sickness behaviors, fever, and pro-inflammatory cytokine activity, between populations and across individuals. These differences in immune function are also consistent with predictions based upon life history, suggesting that disentangling the contribution of these various hypotheses will require both experimental and statistical methods to control for worm burdens.