KAP
Biology Dept
Kenyon College
Mendel's Peacocks
with thanks to Amy's Peacock Paradise
and Peafowl Photo Gallery
Fall Section Spring Section 1 Spring Section 2

Gregor Mendel crossed peas.  Suppose instead he crossed peafowl?

Peacocks and peahens show extraordinary complexity of plumage.  One allele of one gene can alter the entire pattern in unexpected ways--and still show simple Mendelian inheritance.

Examples:
India Blue (B) is dominant to Black Shoulder (b).
Blue (hybrid) Bb x Bb => 3B- : 1bb

Cameo (Zc) is Z-linked recessive to wild type (Z+) (usually India Blue)
Cameo Male ZcZc x Wild-type Female Z+W =>
Wild-type (hybrid) Male  Z+Zc and Cameo Female ZcW

White (T) is codominant with India Blue (B).
TT x BB => All TB; intercross => 1 White TT : 2 White/Blue (hybrid) TB : 1 Blue BB

"India Blue" (wild type) -- Female

"India Blue" (wild type) -- Male

"Black Shoulder" -- Female
bb Recessive to BB India Blue
"Black Shoulder" -- Male
bb Recessive

"Cameo" female
Z-linked (sex-linked, male ZZ)

"Cameo" male (young)
Z-linked (sex-linked, male ZZ)

"White" female TT
Courtesy of: Robert E. McDade Jr., Milledgeville, GA

"White" male TT
Courtesy of: Robert E. McDade Jr., Milledgeville, GA

"Java Green" female (subspecies)
Courtesy of: Pavo muticus conservation project

"Java Green" male (subspecies)
Courtesy of: Pavo muticus conservation project
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