Fishes have been in existence for more than 450 million years, during which time they have evolved repeatedly to fit into almost every conceivable type of aquatic habitat. In a …
Fishes are typically divided into three groups: superclass Agnatha (jawless fishes), class Chondrichthyes (cartilaginous fishes), and superclass Osteichthyes (bony fishes). The …
Bony fish, any member of the superclass Osteichthyes, a group made up of the lobe-finned fishes and the ray-finned fishes of the subphylum Vertebrata, including the great …
The many different kinds of fish have some things in common. They are all vertebrates, which means that they have a backbone. They are cold-blooded, which means that their body …
Living species range from the primitive lampreys and hagfishes through the cartilaginous sharks, skates, and rays to the abundant and diverse bony fishes. Species range in length from 0.4 …
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