Three phenotypes of Snow Goose:
homozygous "blue", heterozygous, and homozygous "snow"
(heterozygotes vary in amount of white on the breast)
A mixed mating with their young
Notice the two dark (blue or heterozygote) and two pale (snow) young
Also the dark adult is a heterozygote (notice its white belly extends far
forward of the legs))
Breeding areas (in arctic) and wintering areas (in NC, LA, and CA)
of "blue" and "snow" morphs of the Snow Goose --
before the expansion of rice agriculture in TX and LA in 1930's
(some "blue" morphs now occur in all areas -- although they are still
most numerous in LA)
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