Answer:
On the basis of physical traits.
Explanation:
Newer classification systems classify organisms on the basis of physical traits of an organism. All modern classification systems gets their concept and help from Linnaean classification system. In these new classification systems, those organisms that have similar characteristics are placed in one group because they evolve from the same ancestor or having common ancestry. These changes occurs in the organisms with the passage of time that helps organisms to survive in that environment.
