Description

as two before, belonging to fishes.Elasmobranch and bony fish from fossil records began, is the development on two lanes, until ***3, when the new materials will be promoted to two separate the two classes, namely chondrichthyes and osteichthyes.
Fishes is one of the biggest extant vertebrate subphylum classes, from the perspective of animal evolution, the outline is the beginning of a jawed, it was for the most primitive, the oldest jawed steel.This is the biggest of the vertebrate subphylum classified groups, in the edge of the devonian has derived a lot of branch, development and evolution has become a fish of various kinds of complicated shape.Fish is divided into existing elasmobranch (classes) and bony fish (class).
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