Each sperm plug the male produces can fertilize one egg - if your dealing with recessive genes than unless you get a visual morph, you won't know who the father is. However if you breed co-doms you have a definite lineage trace, example: a male lesser and a male pastel bred to a spider you know all the lesser spiders, and lessers belong to the lesser, and all the pastels and bumble bees belong to the pastel. Because none of the offspring will be hets, the liniage of the spider and normal babies will be irrelevant.

In short it only makes sense to pair two males to one female if all the genes are co-dom unless the female is recessive and than they can all be properly assumed as het. If that makes sense haha!

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