Supplementary Material s30

Supplementary Material s30

Supplementary Material

Figure S1 Impact of filament shortening on male courtship activity. Time spent in courtship before filament shortening, immediately after shortening and one week after shortening. We used 5 males individually marked with colored Visible Implant Elastomers (VIE Northwest Marine Technology Inc., USA). Each male was placed in a tank (36×33.5×29.5 cm) with a female randomly chosen. Male courtship behaviour was recorded for 40 min with a video camera (Panasonic HDC-TM60, full HD, 1080p) placed above the experimental tank. After cutting the filament (as in experiment 2) we immediately placed the male back in the same tank with the same female to record his courtship behavior for another 40 min. We then housed all 5 males together in the housing conditions described for the experiments 1 and 2. One week later, each male was again placed with a randomly chosen female for 40 min and the courtship behavior was recorded. The videos were analyzed with The Observer 7.0 software (Noldus Information Technology). For each male, we recorded the time spent displaying the fan (courtship activity). The results of this experiment are presented in Fig. S1. They clearly show that male courtship behavior was not negatively affected by filament shortening 1) immediately after shortening, and 2) one week after shortening.

Table S1 Results of PCA on male traits (n=196) including SVL, weight, hue, chroma and brightness. Principal components representing body size, coloration and brightness represented 44.55%, 30.78% and 14.87% of variance, respectively. Cumulative percentage of variance explained is 90.20%.

PCA axis
Eigenvalues
Variance explained / PCbody size
2.23
44.55% / PCcoloration
1.54
30.78% / PCbrightness
0.74
19.30%
SVL / 0.92 / 0.21 / -0.28
Body mass / 0.92 / 0.25 / -0.21
Chroma / 0.22 / -0.85 / -0.16
Hue / -0.29 / 0.84 / -0.03
Brightness / 0.63 / -0.01 / 0.78


Table S2 Summary results of model selection with AICc to explain the number of sperm mass obtained to females in experiments 1 and 2. In exp 1 female had the choice between two males (respectively with high and low filament length). In exp 2 we reversed the relative length of filament before trial. Only models with ΔAICc 2 are presented (ΔAICc = AICci-AICcmin). The bold values indicate the variables presented in every models and w indicates Akaike weights. Fixed effects present in the full models: filament length, hind-foot-web size, crest development, PCbody size, PCcoloration, PCbrightness and courtship activity. For details on the PCA see Table S1. The best model has a coefficient of determination of 33.3% for experiment 1 and 26% for experiment 2.

Predictor / Response / AICc / ΔAICc / W
exp1
No. of sperm
mass transfers / filament, hind-foot-web, courtship activity 0
filament, courtship activity 0
filament, hind-foot-web, body size, courtship activity0
filament, body size, courtship activity0 / 73.9
74.1
74.14
74.81 / 0
0.19
0.23
0.91 / 0.29
0.26
0.26
0.19
exp2
No. of sperm
mass transfers / hind-foot-web, courtship activity0
courtship activity0
coloration, hind-foot-web, courtship activity0
coloration, courtship activity0
filament, hind-foot-web, courtship activity0 / 112.16
112.63
113.25
113.74
114.16 / 0
0.47
1.09
1.58
2 / 0.31
0.25
0.18
0.14
0.12