Hi, I have a betta fish. 
Those fish are great! They're small so you don't need a big aquarium and they have such beautiful colors!
I agree, they also dont need much food so they are low maintenance (unlike my wife).
Ha! Bettas are also known as Siamese fighting fish! Hopefully also unlike your wife!!
Siamese fighting fish? Can you tell me more about this? 
These fish are extremely territorial! They have extremely high levels of aggression toward each other. That's why they're always kept alone in their bowls.
I see, perhaps they might serve better as food than pets. Would you agree?
Maybe so! Betta owners even have to be careful when trying to breed their fish! The male and female can only share their space for a very short time, or they kill each other. Ha! 
Thats is rather shocking! I wonder what evolutionary purpose such aggression may have served. 
That's a great question! One more interesting thing about betta fish is that they can breathe atmospheric air. That's how they're able to survive in bowls which would kill most other types of fish.