Why is a beta considered fish if it breathes air?

This is a bit of a tricky question, and it highlights how we sometimes use common names in a way that isn't always scientifically accurate. Here's the breakdown:

* Beta fish are classified as fish: They belong to the taxonomic order Perciformes, which is a group of bony fishes. They have fins, scales, and a streamlined body, all features that align them with other fish.

* They breathe air, but they also need water: Betta fish are labyrinth fish. This means they have a special organ called the labyrinth organ that allows them to breathe air directly. However, they still need to live in water, as they absorb oxygen through their gills.

* Common names don't always reflect scientific classification: The term "fish" isn't always used in a strict scientific sense. Sometimes it's used more broadly to describe aquatic creatures, even if they don't strictly fit the scientific definition of fish.

In short: While bettas do breathe air, they are still fish. Their unique ability to breathe air is just one adaptation that allows them to thrive in environments with low oxygen levels.