Insufficient information. It could well be sick or hiding from other occupants.
Intrusion..!
If there are fish small enough for the molly to swallow in the tank with them then they will most probably be eaten. They will eat their own young.
It is generally safe to keep a pregnant Dalmatian Molly in a community tank with other fish, as long as the tank is well-maintained and the other fish are not aggressive towards the pregnant fish. However, it is important to monitor the pregnant fish closely and provide a separate breeding tank if needed to ensure the safety of the fry.
It is a risk. Every fish you put in a tank has a risk of fighting
If your female Molly has been in the same tank with a male molly then you can almost guarantee that she will be gravid (pregnant). If she is behaving in a touchy and skittish manner doing short dashes from place to place near the bottom of the tank then it is quite possible she is letting her young free (giving birth).
Dalmatian molly fish typically prefer open swimming areas and are not known for hiding in rocks like some other fish species. They thrive in well-planted aquariums where they can find cover among plants and decorations. While they may seek shelter occasionally, they generally do not make rocks their primary hiding spots. Providing a variety of habitats in the tank can help them feel secure.
The female will have a very rounded belly and most of the time looking at them from the top of your tank their body will appear wider than normal. In some instances the gravid spot will become darker as the female get closer to giving birth.
Bottom of the air tank. Used to drain the water in the bottom off the tank
Yes, large enough tank and plenty of hidding spots. I have two in a 30x12x12, as long as you dont place a female with two males then they will fight over her
It would not kill the Molly, however it would seriously harm the Molly and shortly after the Molly would have very difficult challenges to live.
I have never had any problems with swordtails. I have 1 male and 2 females in a tank with 2 angelfish, 1 serpae tetra, 1 blue gourami, 1 dalmatian molly and 1 mickey mouse platy. There will always be exceptions to the rule but, as far as my experiences go, they are not.
Because they're tired.