Latent preference for red ornamentation drives interspecific mating in nascent jumping spider species (Habronattus americanus group, F. Salticidae).
Heterospecific interactions between nascent species offer insights into how sexual selection shapes novel traits, illuminating patterns in species interactions and diversification. We tested female preferences between two recently diverged, allopatric species of jumping spiders: Habronattus americanus PLC, with red-coloured males performing short multimodal displays, and Habronattus sansoni CC, with brown-coloured males performing long multimodal displays. Mate choice experiments showed that females of both species preferred H. americanus PLC males. To examine the role of red coloration, we manipulated male coloration in both species. Results indicated that red-painted H. sansoni CC males experienced an increase in mating success, whereas brown-painted H. americanus PLCmales did not show reduced success. Our study suggests that (i) strong latent female preferences can drive unidirectional introgression across species boundaries, potentially leading to genomic homogenization; (ii) latent preferences may override preferences for existing traits; and (iii) the geographical distribution of colour morphs is consistent with a hypothesis of strong latent preferences across populations. Overall, our study demonstrates the role that mating interactions can play in speciation dynamics.