Data from: Equivalent effect of UV coloration and vibratory signal on mating success in a jumping spider

Ultraviolet (UV; wavelengths: 280–400 nm) colouration has been shown to be
an important visual signal but has not been studied in conjunction with
other signals such as vibratory signals previously. Here we investigated
multimodal signal function in the visual and substrate-borne vibratory
modalities of the UV-ornamented jumping spider Cosmophasis umbratica, in
which the importance of UV colouration in courtship displays has been
demonstrated. We first described vibratory signals produced by courting
males. We found that while vibratory signals mainly consist of palp
drumming and abdomen thump, amplitude of abdomen thump shows a high
variance and is positively correlated with body mass. This suggests that
abdomen thump as a vibratory component may be condition-dependent. To
examine whether the vibratory and UV signal function as backup to each
other in a variable environment (efficacy-based backup hypothesis), we
used a fully crossed 2 × 2 mating assay, a signal-isolation approach, to
investigate how isolated and combined signals affect mate choice by
females. Our results showed that both signals in isolation or in
combination result in similar female responses (i.e., mating success,
latency to copulation, female attention ratio). The presence of both
vibratory and UV signals affects mating frequency, with no significant
differences in mating frequency when vibratory and UV signals are
presented in isolation or in combination. These results support the
efficacy-based backup hypothesis. We therefore conclude that vibratory and
UV signals have equivalent effects in predicting mating success in C.
umbratica.