The females may want to establish nests; for two pairs (2 males and 2 females) you should provide three nests so they don't have to fight. Also, the males will try to mate with both females if they can, this can also cause fighting.
One time one of my females had eggs and the other didn't. The one that didn't have her own eggs wanted to sit on the eggs belonging to the first one. That caused fighting, but it was OK for the other male to sit on the eggs!
If the cage is too small for so many birds you should separate them.
you dont have to buy them in pairs, but most people get a pair of zebra finches so they can keep company, or to breed them cause breeding zebra finches is really easy .
Zebra finches are from Australia
after their first molt, the males will have red cheeks and will keep them the females dont
zebra finches only eat seed
I did a little bit of research and I'm just getting that zebra finches do well with other zebra finches; not any other kind. Hope this helps, although I do have two zebra finches that continuously peck at one another. So it may be a sign of playing? Keep a close eye on them and make sure they don't hurt each other.
No, zebra finches can also be found in pet stores outside of Australia.
Zebra Finches can't talk, but one of my Pied Zebra Finches make a call that imitates the sound of an alarm. My Zebra Finches do answer me, though. When I walk in the door and say "Hi" to them, they chirp back. Zebra Finches can make beautiful calls, so without tricks, these cute little birds put on a show...with their singing! Thanks, Grace's Finch Care
Most domesticated zebra finches are timid and fly away from humans who approach them. They CAN bite, though. It has known to be quite painful according to the sharp beak. I have zebra finches and none of them have bitten me before.
because keeping multiple males caged together is risking dominence-related aggression
O Zebra finches are social birds and should never be kept alone unless they are being quarantined for an illness or a new aquire...
YES
If for some reason your bird's testosterone level drops, he will sing less frequently or ... with certain kinds of finches such as society or zebra finches.