Question

11. Male American goldfinches grow yellow feathers during the mating season and will attack another goldfinch in its territory if it also has yellow feathers. What term describes the yellow feather stimulus in this example?

Answer 1

This is called sexual dimorphism or plumage dimorphism in particular. During mating season male American goldfinches shed and grow bright yellow feather to attract female goldfinches, the brighter the color higher the chance to find a mate.During this season, the male goldfinch is aggressive in attacking males who goes into his territory. 

Answer 2

Its releaser best describes the yellow feather stimulus.  

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