black mollies genes

Question
I read your answer about "albino" being a recessive gene.  My daughter started with one yellow female molly and one black male molly. So far they have had approximately sixty fry that are still alive (between three and four pregnancies).  The oldest "baby" is about six months old.  The youngest is about one month old.  There are many yellow or white offspring and many yellow with black dots (we call them leopard mollies, but perhaps they are dalmatian mollies?).  There is not one single black offspring.  Is it possible to mate a black molly with a yellow molly and have black offspring?  Perhaps we just have the "wrong" black molly or perhaps only two black mollies can produce other black mollies?  Anything you can tell me about this issue, even other places (books, websites) we can look at, would be greatly appreciated.

Thank you.

Answer
Hi Kathryn,
 Hmm... I don't recall writing any answer about molly genetics.... are you sure that was me?

 The tricky thing about some livebearers such as mollies is that they can store sperm, meaning that the kids that you see now are not necessarily all from the latest mate.  

-- Ron
  rcoleman@cichlidresearch.com
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