There is no actual statistic for this, but I have had litters of 8 with all males.
Only if you devide the cage first, so they can not get to each other. If they are allowed to get to each other, they will fight.
the genes for twins only matter on your mother's side. Having a male partner with a history of twins will not affect you.
No but if you get it a friend, make sure that they won't kill each other. A gerbil is a pack creature and normally has a friend. If you only have one, it might lonely but it will be fine.
The occidental gerbil is found only in Morocco
If both parents have the gene, the chances are 25% of having a child with Cystic Fibrosis. The male and females x genes are affected by it and only half of it. So when the parents mate and they are going to have a baby, the chances are 25%
yes but only if you are expecting baby gerbils.
Gerbils only produce minimal waste as they are desert animals. This means you only have to clean their tank once every two months.
Washing a gerbil is normally only done when a gerbil is going to be competitivly shown or needs to get wounds washed (only to be done by a vet). Nearly all pet gerbils will never have to be washed. Do not wash your gerbil without advise from your vet.
Look on his back side. If it is a Female there are no lumps, the gaps between each ahem holes are larger on a male and smaller one a female. also it is like a baby kitten. the only way you can tell its balls. if it has some then its a boy.
I tried to train my gerbil and it took longer than i thought. I figured out that the only way to train your gerbil is to use treats and have alot of patience!
Only if it is a black gerbil.
Only if you hold by the very tip. Other wise, your gerbil won't be hurt by you holding it by its tail.