Meeting Abstract

60.1  Thursday, Jan. 6  The dynamics of physiology-trait relationships: implications for honest signal theory SAFRAN, Rebecca J.; University of Colorado, Boulder rebecca.safran@colorado.edu

An implicit assumption underlying several models within current sexual selection theory is that the physiological costs of sexual signals are static or fixed. In particular, the handicap and good genes indicator models of sexual selection both indicate that the physiological underpinnings of morphological traits used to assess potential mates and competitors are constant such that conspecifics can infer a number of physiological attributes associated with that signaling trait. However, in two separate studies conducted on barn swallows Hirundo rustica, we show that physiological variables typically studied along-side morphological signals (circulating testosterone and antioxidants) are dynamically – rather than statically – related to various aspects of an individual’s morphology. Here, we summarize empirical findings related to the physiological underpinnings of a known sexual signal – ventral color – in barn swallows and suggest a new framework for interpreting morphology-signal dynamics, central to assumptions within several models of sexual selection.