Sampling and housing
The males of S. occidentalis used in this study (N = 42) are the
same as those used in Megía-Palma et al (2018b, 2020). The housing
conditions have also been described elsewhere (Megía-Palma et al. 2020).
A residual body condition index was calculated as the residuals of the
regression between the log-transformed values of body mass and
snout-vent length of the lizards (Dunlap & Mathies 1993). A sample of
blood (< 10 µL) and fecal pellets from the lizards were taken
to diagnose infections by both hematic and intestinal coccidians (see
Megía-Palma et al. 2018b). The number of ticks and the presence of mites
were recorded. We measured the spectral reflectance of the yellow and
blue color patches, the throat, and the back with an Ocean Optics 2000
spectrophotometer (for details see Megía-Palma et al. 2018b). In
addition, total surface of the blue patches was calculated by
multiplying its length by its width. Both were measured with a ruler to
the nearest mm. The area of the blue patch was correlated with the SVL
of the individual (F1, 40 = 7.19, P = 0.010). We
calculated the residuals of blue patch area on SVL to remove this
effect. Thus, higher values of (residual) blue patch area indicated
lizards with proportionally larger blue patches. The lizards were
released at the end of the trials to their original site.