neural circuit may be ancestral and functions within the mediation of stress responses. We presume that the multiple phenotypes associated with corazonin neurons reflect multiple primary effects of altered corazonin neuropeptide secretion as well as secondary indirect actions. Clearly, hormonal signaling systems can impact multiple tissues depending on the scope of receptor distribution, as well as initiate a sequence of endocrine events via the regulation of other hormones. Further studies aimed at addressing phenotypes associated with the corazonin receptor may offer insight into the specific mechanisms of corazonin actions in regards to stress- altered behaviors. Supporting Information Figure S1 Effect of age on physiological stress sensitivity. We assessed the impact that an animal’s age had on starvation and osmotic stress sensitivity. We isolated thirty age-matched individ- uals and assessed mortality as described in text. Median survival +/2 SEM was determined from three replicates and fifteen day old female flies have lower survival than 3 day old and 10 day old animals (P,0.05, ANOVA), whereas while there was a general trend in lower lifespan in males as a function of age there was no statistical difference. Found at: doi:10.1371/journal.pone.0009141.s001 (1.79 MB TIF) Figure S2 Lifespan in animals with corazonin neuronal manipulations. To evaluate absolute lifespan, animals were placed in vials containing normal food media after being collected and co- housed for three days. Animals were subsequently sorted by sex and placed in vials with normal media in groups of thirty. Vials were changed once every three days and mortality was assessed once daily. Males with ablated corazonin neurons are long-lived as compared to w1118 or Crz-GFP (P,0.05 ANOVA), and females with ablated or silenced corazonin neurons are longer lived than w1118 (P,0.05, ANOVA), but are comparable to Crz-GFP. 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