What are the limitations of Aristotle's classification?

Explanation

Many organisms were not fitting into his classification. Frogs have lungs and they are amphibians while their larva, tadpole is aquatic and respires through gills. It is difficult to classify frogs according to his method. All flying organisms such as birds, bats, flying insects were grouped together. Ostrich, emu and penguin are flightless birds and hence they cannot be classified by his method.