Google wil give more information
The Chondrichthyes are the cartilaginous fishes including the sharks, rays,<span>skates and chimeras. The Osteichthyes are the bony fish. Both of these groups </span>became established during the Devonian Period about 400 million years ago. The Chondrichthyes <span>differ from the Osteichthyes in many respects, including their</span><span>
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Plate movement impacts the folding of this layer.
That is true, species can breed within