How relaxed preferences facilitate the evolution of novel animal signals

The evolution of novel animal signals is critical to the generation of biodiversity. Here, we explore how new sexual signals become established. This process is challenging to explain because if receiver preferences are coupled with existing signals, then most receivers should discriminate against new signals. We investigated an underappreciated hypothesis: relaxed receiver preferences facilitate novel signal evolution by allowing new signals to establish a foothold. Further, we probed the mechanistic underpinnings of relaxed preferences by combining field-based and common garden approaches, allowing us to investigate evolution and plasticity as mechanisms. We capitalized on the Pacific field cricket, Teleogryllus oceanicus, a species that has recently evolved multiple novel acoustic signals (e.g., purring and rattling) in response to an eavesdropping parasitoid fly only found in the crickets’ introduced range in Hawaii. To test the hypothesis that selection associated with high search ..., Field-based Phonotaxis Tests
We collected reproductively mature adult female T. oceanicus at six field sites: two replicate sites in Queensland, Australia (Cairns and Daintree) in February of 2023, two in French Polynesia (Tahiti and Mo’orea) in December of 2023, and two in Hawaii (Hilo and Wailua) in December of 2022 (Figure S1, Table S1) using methods that are not biased with respect to song, sex, or life stage. Briefly, rather than locating individuals by sound, we swept by foot in the fields where the crickets are found, collecting animals visually such that all life stages, sexes, and morphs were encountered (following Tinghitella et al. 2018; Tinghitella et al. 2021). Upon collection, we took the animals to local field stations where we housed females in 15L plastic storage containers with rabbit food ad libitum, egg cartons, and cotton with water under natural day-night cycles (at a density of ~30-40 females per container). We acoustically isolated females from calling males for ..., # How relaxed preferences facilitate the evolution of novel animal signals

Dataset DOI: [10.5061/dryad.t76hdr8ds](https://doi.org/10.5061/dryad.t76hdr8ds)

## Description of the data and file structure

The phonotaxis and behavior data for both the lab and field are located in the file titled \"Welsh_behavior_data.csv.\" The data used to make the heatmap are located in the file titled \"Welsh_heatmap.csv,\" and the hearing model data for Figure 5 are located in \"Welsh_hearing_model.csv.\" The data used to make Figure S2 in the supplement are in \"Welsh_supernormal.csv.\"

### Files and variables

## Welsh_behavior_data.csv

**tripID:** season and year in which the field trip to collect data took place. W22.23 indicates winter 2022-2023, F24 indicates Fall 2024, etc. Lab trials have an \"na\" since the data were not associated with a field trip

**region:** one of three broad locations with cricket populations- Australia, French Polynesia, and Hawaii. Each region had two replicate populations

*...,