Solution

Animals are classed based on shared characteristics such as cell organisation, body symmetry, coelom type, digestive tract, circulation, and reproductive system. It is impossible to handle each creature uniquely without these common traits, and it is impossible to add new species discovered every day without them. To investigate animal diversity, classification must be based on common basic characteristics.

Other challenges include:

(i) tracing interconnectedness among different animals will be tough. (ii) Difficulty in creating new animal species