A case of natural selection

My pair of albino bengalese finches have this year shared the aviary with the young normal male I bred last year. Despite knowing it is common with these finches, I was still surprised that all 3 shared the incubation and now rearing of the chicks. It looks like all the chicks are normal. Perhaps this is case of natural selection of the dominant normal colour over the mutation.

The turq chicks are growing fast...

Pair 2 chicks