Brood Parasitism Defense Behaviors Along an Altitudinal Gradient in the American Robin (Turdus Migratorius)

Table 1: Description of artificial egg types used in experimental parasitism experiments. The abbreviation used for each egg type and the number of character differences between an American robin egg and a brown-headed cowbird egg are noted.

Egg Types (Size, Color, Spotting)	Egg Type Abbreviation	Number of Differences
Robin, Blue, Immaculate^†	RBI	0
Robin, Blue, Spotted	RBS	1
Robin, White, Immaculate	RWI	1
Cowbird, Blue, Immaculate	CBI	1
Robin, White, Spotted	RWS	2
Cowbird, Blue, Spotted	CBS	2
Cowbird, White, Spotted^†	CWS	3

^† mimetic robin egg.
^† mimetic cowbird egg.