The same thing happened to me, I bought 2 female gerbils from the pet store and then found babies in the cage one morning. Check online pictures of male and female gerbil genitalia so you can determine which one is the male. You need to put the male in a separate cage or they will keep mating and making more babies. Gerbils mate again right after the babies are born, so you might end up with another litter even after you separate them. Keep them separate unless you want to breed them, or you will end up with a ton of gerbils! Here's a link to find pics of the gerbils genitalia: http://www.gerbils.co.uk/gerbils/gender.htm
um no, only female gerbils can
Male gerbils can be neutered, but it is not recomended. Female gerbils should not be spayed. In general male gerbils should not be neutered unless there is a good reason for it.
yes
Yes. Male gerbils, no matter how old they are, can impregnate female gerbils. Most female gerbils can no longer conceive after 2 years of age. Either way, it's never wise to put a male and female together unless you intend to breed and provide for several litters. Gerbils are not easy to find homes for.
Only if you give them crank.
No I have two female gerbils (Minnie and KE$HA) and KE$HA is clearly older and they get along fine.
...You are kidding, right? Gerbils are mammals; some of them are male, and some are, well, female. They reproduce the way mammals do.
I'd be interested to know where you heard that as I've done necropsies on female gerbils and have not found that to be true.
Gerbils go into heat ever 4 day. There are no outward signs that they are in heat, unless a male is in the tank (in which the male will attempt to mate with her)
About 28 days after the female gets pregnant.
Gerbils do not have periods as they are oestral mammals and not menstrual ones like us. Some oestral mammals have a bloody discharge, but not gerbils. What you saw was most likely to be a smear of porphyrins from a gland near the gerbil's eye.
no male gerbils are very caring so dont split them up