I purchased these 2 dalmatian mollies today & the bigger bellied one was nipping & chasing the smaller one while they were in the bag on the way home, so I looked at their fins figuring I may have gotten a male & female. her analfin indeed looks female, & I read when they are pregnant sometimes they can feel threatened in small spaces & act that way. since putting them in the tank they have acclimated well, there is no fin nipping or chasing but I am still wondering, does she look to be pregnant? I have had mollies before but never one with a belly so big, besides the balloon bellied mollies. both seem to be female, but she is much bigger in the belly than the other.