Table 2.

Paired t-tests comparing the eumelanin (A) or pheomelanin (B) contents between organs in the barn owl

A. Eumelanin	Skin	Pectoral muscle	Eye	Heart	Liver	Trachea
Pectoral muscle	t = 8.17, p < 0.0001
Eye	t = − 60.63, p < 0.0001	t = − 60.80, p < 0.0001
Heart	t = 15.35, p < 0.0001	t = 10.11, p < 0.0001	t = 60.82, p < 0.0001
Liver	t = 3.43, p = 0.002	t = − 6.83, p < 0.0001	t = 60.74, p < 0.0001	t = − 21.24, p < 0.0001
Trachea	t = 11.31, p < 0.0001	t = 4.95, p < 0.0001	t = 60.82, p < 0.0001	t = − 5.67, p < 0.0001	t = 13.02, p < 0.0001
Uropygial gland	t = 18.42, p < 0.0001	t = 16.06, p < 0.0001	t = 60.89, p < 0.0001	t = 60.89, p < 0.0001	t = 11.39, p < 0.0001	t = 29.69, p < 0.0001
B. Pheomelanin	Skin	Pectoral muscle	Eye	Heart	Liver	Trachea
Pectoral muscle	t = − 14.89, p < 0.0001
Eye	t = − 29.02, p < 0.0001	t = − 27.03, p < 0.0001
Heart	t = − 16.58, p < 0.0001	t = − 6.71, p < 0.0001	t = 25.81, p < 0.0001
Liver	t = − 14.59, p < 0.0001	t = − 0.66, p = 0.52	t = 27.78, p < 0.0001	t = 7.17, p < 0.0001
Trachea	t = 5.65, p < 0.0001	t = 24.26, p < 0.0001	t = 29.65, p < 0.0001	t = 22.60, p < 0.0001	t = 25.38, p < 0.0001
Uropygial gland	t = 7.67, p < 0.0001	t = 25.35, p < 0.0001	t = 30.11, p < 0.0001	t = 22.43, p < 0.0001	t = 24.95, p < 0.0001	t = 3.15, p = 0.0045

All degrees of freedom are 23 and tests were performed on the Box–Cox transformed data. Cells are in gray when the melanin content of the organ indicated in the top row is higher than the melanin content of the organ indicated in the first column. For example, the skin has more eumelanin than the pectoral muscle but less than the eyes