The "flaring" of the gills is simply a way for the fish to look larger and more threatening. It is both defensive and aggressive behavoiur.
It is an adaptation that they have developed to defeat other siamese fighting fish for mates and/or territory.
The gills of a shark (and other fishes) extract oxygen from the water, allowing the shark to breath.
all the piranhas have gills ..they cant breath under water without gills ...it is like all the other fishes
Typically they will flare their gills at each other and begin swimming around each other very closely, it's actually difficult to really see that they are fighting. My suggestion, don't keep 2 male bettas in the same tank.
They might have fought each other.
No, clownfish, like other fishes, have gills.
It may be, but look for other signs. Does it move at all when you move its tank or bowl? Can you see its gills move? Watch it for a whole hour to see if it moves. If not then it may be dead.
Exactly as you spelled it in your question; a Betta fish is also known as a Siamese Fighting Fish.it is spelled "Betta", or its other name, "Siamese Fighting Fish." I know alot about Betta's. :D
Two males will kill each other.
Fighting fish are territorial and can be very aggressive, they will kill other fish if you put them in the same tank.
you can not keep two males together as they do fight each other
Liolik answers: The Siamese fighting fish