picture of the week help

[F50myster]

this weeks picture of the week is weird because the silver seabright has a single comb i though that all silver seabrights had rose combs or spiked rose combs can someone please help me out on this

 

[F50myster]

 

[canada-goose]

Sometimes rose combed birds have single combed offspring. Such birds can't be shown, but they do happen.