This project includes the supplemental appendices for the preprint titled "Bird Eye Color: A Rainbow of Variation, a Spectrum of Explanations." Any suggestions for further examples to add to these appendices are welcomed! Contents of the supplemental appendices are as follows: Appendix 1: Phylogenetic Patterns of Variation Appendix 1a: Eye Color of Bird Families. As determined by Worthy (1997) and following his taxonomy. For full details on category assignment, see Worthy, but in short, irises are categorized based on the lightest color reported in the literature, and colors are categorized as follows: 0.00- yellow, white; 0.25- orange, pink, blue, green; 0.50- red, gray, chestnut; 0.75- brown; 1.00- black. Prefixes light- and dark- lower or raise the score by .25, respectively (e.g., light brown is scored as 0.50) Appendix 1b: Genera with Variable Eyes. This is a non-comprehensive list of bird genera that show notable variation in eye color. Generally, genera were included if they comprise species with 3 or more distinctly different eye colors, or if different eye colors has been shown to evolve multiple times within the phylogeny. Data are from the Birds of the World database (Billerman et al. 2022). Any additional citations are included in the notes. Appendix 1c: Species Pairs. This is a non-comprehensive list of bird sister species pairs which differ markedly in eye color. Appendix 2: Intraspecific Variation Appendix 2a: A non-comprehensive list of species that show marked sexual dimorphism in eye color. Appendix 2b: A non-comprehensive list of species that show marked geographic variation in eye color. Appendix 2c: A non-comprehensive list of species that show seasonal variation in eye color. Appendix 2d: A non-comprehensive list of species that appear to show marked eye color variation among adults of the same age, sex, and location. In most cases, greater study is needed to assess the cause(s) of this variation Appendix 3: Mechanisms of Iris Coloration. A list of bird species in which pigments and/or structures that influence eye color have been identified.