Two chambered heart is present in fishes.
- Fishes belong to class Pisces, which have two chambered heart, while amphibians and reptiles have three chambered heart and birds have four chambered heart.
- Fish are cold-blooded vertebrate species that can be found in both freshwater and saltwater all over the world.
- Hagfishes, sharks, bony fishes, and other fishes belong to the superclass Agnatha and phylum Chordata, that comprises hagfishes, sharks, and other bony fishes.
- All fishes, except the Opah, are cold-blooded vertebrates.