Greetings again from San Francisco! Day One of SICB has been full of amazing talks and posters. The poster session yielded interesting new research by Diego Castro and Michele Johnson, of Trinity University, on the relationship between testosterone and dewlapping behavior. Diego, an undergraduate studying neurobiology, asked whether muscles involved in sexual or aggressive behavior would have increased testosterone. To answer this question, Diego focused on five species of Dominican anoles, including Anolis brevirostris, A. coelestinus, A. cybotes, and A. olssoni. Diego observed the natural behavior of these species, and quantified the average number of pushups and dewlaps they performed. They found that A. coelestinus and A. cybotes have fewer dewlap extensions and several pushups in their displays, while A. brevirostris dewlaps as often as it performs pushups. They then quantified the concentration of androgen receptors in the ceratohyoid, which controls dewlap extension to determine whether levels of androgen receptor protein correlate with sexual display behavior. They found that species with greater display rates also had a higher number of cells expressing androgen receptor protein. Their next goal is to measure androgen receptor protein in the bicep and tricep. Great job, Diego!