Mating history reveals within-individual integration of multimodal signaling effort in a pseudophylline katydid

Abstract Sexual advertisement often involves multimodal signals whose expression may be integrated differently among and within individuals. When signals overlap in function, patterns of covariation in signaling effort can indicate whether they operate as coordinated components of a complex display, alternative tactics, or independently evolving traits. However, these patterns can be obscured by plasticity in signaling effort in response to fluctuations in environments and individuals’ internal states. Using a katydid species ( Docidocercus gigliotosi ) that produces both airborne and substrate-borne sexual advertisement signals, we tested whether multimodel signaling efforts were more strongly influenced by persistent individual differences or short-term intra-individual plasticity. We recorded wild-caught males for repeated 24-hour periods over multiple weeks and examined how individual identity, experimentally manipulated mating history, and other factors affected signaling effort in each modality. We found that plasticity during a transient refractory period after mating accounted for most of the overall variation in signal production. Over six weeks, unmated males increased stridulation effort more than males that had mated immediately before the first week of recording, suggesting a more persistent effect of mating history on sexual advertisement behavior. Male body condition, moonlight intensity, and recording location were also associated with variation in calling effort. Together, these results indicate that multimodal signaling effort in D. gigliotosi is shaped more by coordinated within-individual plasticity than by fixed among-individual signaling strategies. They also suggest that airborne and substrate-borne calls function as complementary components of mate advertisement over daily timescales rather than full functional equivalents.