This archive contains five files with data and scripts to replicate the modeling analyses presented in Toomey and Ronand 2021 Toomey and Ronald_HOFI_model_data.xlsx is an excel file with six sheets: 1. Plumage spectra - House finch plumage spectrum measures (% relectance) collected following methods in: Butler, M., Toomey, M. and McGraw, K. (2011). How many color metrics do we need? Evaluating how different color-scoring procedures explain carotenoid pigment content in avian bare-part and plumage ornaments. Behavioral Ecology and Sociobiology 65, 401–413; 413. and including birds sampled as part of: Toomey, M. B. and McGraw, K. J. (2009). Seasonal, Sexual, and Quality Related Variation in Retinal Carotenoid Accumulation in the House Finch (Carpodacus mexicanus). Funct. Ecol. 23, 321–329. 2. Irradiance - Normailized irradiance spectrum from: Lind, O., Henze, M. J., Kelber, A. and Osorio, D. (2017). Coevolution of coloration and colour vision? Philos. Trans. R. Soc. Lond. B Biol. Sci. 372 3. Ocular media - Zebra finch ocular media transmittance from: Lind, O., Mitkus, M., Olsson, P. and Kelber, A. (2013). Ultraviolet vision in birds: the importance of transparent eye media. Proceedings of the Royal Society B: Biological Sciences 281, 20132209–20132209. 4. Cone parameters include the cone visual pigment lambda max values for the canary: Das, D., Wilkie, S. E., Hunt, D. M. and Bowmaker, J. K. (1999). Visual pigments and oil droplets in the retina of a passerine bird, the canary Serinus canaria: microspectrophotometry and opsin sequences. Vision Res. 39, 2801–2815. and zebra finch cone abundances from: Lind, O., Henze, M. J., Kelber, A. and Osorio, D. (2017). Coevolution of coloration and colour vision? Philos. Trans. R. Soc. Lond. B Biol. Sci. 372 5. Plumage carotenoid content - measured by HPLC - data from: Butler, M., Toomey, M. and McGraw, K. (2011). How many color metrics do we need? Evaluating how different color-scoring procedures explain carotenoid pigment content in avian bare-part and plumage ornaments. Behavioral Ecology and Sociobiology 65, 401–413; 413. 6. Cone oil droplet spectra - house finch normalized expanded cone oil droplet spectra measured following methods described in: Toomey, M. B., Collins, A. M., Frederiksen, R., Cornwall, M. C., Timlin, J. A. and Corbo, J. C. (2015). A complex carotenoid palette tunes avian colour vision. J. R. Soc. Interface 12, 20150563. Plumage_OD_HOFI_dS_example.R - contains an R script to respoduce that analysis of chromatic contrast variation presented in Figure 3B of Toomey and Ronand 2021. This analysis was completed using R version 4.0.3 (2020-10-10) with the Tidyverse family of R packages. This script will call for you to load the "Plumage_OD_eye.RData" that contains base data to run the model. This base data is also included in .xlsx file. Carotenoid_OD_HOFI_example.R - contains an R script to respoduce that analysis of chromatic contrast variation presented in Figure 3E of Toomey and Ronand 2021. This analysis was completed using R version 4.0.3 (2020-10-10) with the Tidyverse family of R packages. This script will call for you to load the "Carotenoid_OD.RData" that contains base data to run the model. This base data is also included in .xlsx file.