DT question

[Auratus]

Why are double tailed betta's dorcal fins so long? Is it connected to the fish's body or is it just like that when it flares? I was wondering because I saw this fish on aquabid:
http/www.aquabid.com/uploads/fwbettaswt1089093834.jpg

 

[cutecotton]

i think i'ts that way because dts literally have TWO tails, and yeah i think it's connected to the boyd too. Wtih teh two tails, everything is twice as large, espiecally the dorsal fin.

i'm not SURE though beucase i don' thave a dt

 

[jacblades]

i dont htink all dt bettas have long dorsal fins. i dont think it has anyhting to do with twice as much finnage for the ones that do.