I can’t explain the exact science behind it but it all comes gown the the “color inheritance” in the case with labradors, chocolate dogs can “drop black dogs because of the dominant genes of the black color, Because black is a dominant gene (BB) where yellow is (Bb) and chocolate is (bb). The color they are doesn’t necessarily predict the color of the puppies it is the genes they carry. For that reason many “breeders” get their dogs tested and it can tell you the odds of having the different colors depending on what the other dogs genetics may be.
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