Summary of published studies using observational tests of the relationship between intraclutch egg appearance variability and rejection rate by hosts of obligate brood parasitic birds.^{^a}

a “Parasite Mim./Nonmim.” indicates whether natural parasitic eggs mimic those of hosts. “Correlation” indicates the direction of correlation (if any) between color variation within (“Correlation intra-”) and between (“Correlation inter-”) and the rejection rate of parasitic eggs. b Studies that compared inter- and intraclutch color variation between 2 populations, one in sympatry and one in allopatry with cuckoos. Positive correlation for interclutch color variation is derived from statistical difference between these two populations. Lack of correlation for intraclutch color variation is derived from lack of statistical difference between these two populations. Summary of published studies using observational tests of the relationship between intraclutch egg appearance variability and rejection rate by hosts of obligate brood parasitic birds.a