Grouping of all living beings with more or less complex organs, with which they move about and feed themselves; the body of knowledge about them.

FISHES

Cold-blooded aquatic vertebrates (about 30,000 species) having motor fins and bodies that are usually covered in scales.

cartilaginous fish

Fish whose skeleton is made of cartilage rather than bone; its skin is covered in hard scales called denticles. There are currently 700 species.

Fish with a rigid skeleton and smooth flat scales; the 20,000 present-day species make up the largest group of fish.


morphology of a perch	anatomy of a perch