Figure 4From: The carotenoid-continuum: carotenoid-based plumage ranges from conspicuous to cryptic and back againDetectability of carotenoid-based plumage against natural backgrounds compared with other cryptic plumages and within-background contrast. Detectability was computed against average brown (above) and green (below) backgrounds. Within-background contrast depicts the level of contrast between different types of backgrounds (see Additional File 2) and the global brown (above) or green (below) averages. Boxplots depict maximum and minimum, 75 and 25 quantiles and median. Dots represent outliers.Back to article page