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Table. 1 Effects of colour differences between targets and backgrounds on detection risk in survival models

From: Generalist camouflage can be more successful than microhabitat specialisation in natural environments

Explanatory variable
Colour difference metric Area Distance from model z HR CI χ21 p AIC
∆E (CIEDE2000) Near zone 10 m 8.56 1.064 1.049–1.080 74.691 < 0.001 7882.001
∆E (CIEDE2000) Near zone 30 m 7.98 1.056 1.042–1.071 63.803 < 0.001 7891.923
∆E (CIEDE2000) Whole image 10 m 7.44 1.054 1.039–1.068 55.802 < 0.001 7901.507
∆E (CIEDE2000) Whole image 30 m 6.39 1.046 1.032–1.061 41.093 < 0.001 7916.372
Strategy − 5.84 0.543 0.443–0.667 37.779 < 0.001 7919.648
Null 7958.985
  1. Models are ranked by increasing AIC, including the model testing the effect of strategy (generalist/specialist) for comparison. Photographs taken from two distances away from the model (10 m/30 m) were used to measure coloration in different areas (near zone around the hare model/whole image), and differences between hares and backgrounds were measured as ∆E (CIEDE2000 formula). Hazards ratios (HR) > 1 indicate that increasing difference between models and background areas increases detection risk. The HR for the Strategy model corresponds to decreased risk for generalists compared to specialists. The null model includes the same random effects as all other models, but no strategy or colour difference variable