Diversity of chordates

Numerical strength-Means 49000 species of animal kingdom i,e 1/2 of molluscs and1/10 arthropoda.urochordata & cephalochordata-2500 speacies.vertebrata-46500speacies.fishes-25000 species.amphibians-2500.reptiles-6000.birds-9000.mamals-4500.