What is the basis for the earliest classification system of organisms?

What was the basis of early classifications? The earliest classification systems comprised of only two kingdoms but with more research, more kingdoms were added with time. The two kingdom system of classification was given by Carolus Linnaeus. He divided all organisms into two kingdoms, Plantae and Animalia.

Explanation:

Aristotle developed the first system of classification of animals. He based his classification system off of observations of animals, and used physical characteristics to divide animals into two groups, and then into five genera per group, and then into species within each genus.

The earliest classification systems comprised of only two kingdoms but with more research, more kingdoms were added with time. The two kingdom system of classification was given by Carolus Linnaeus. He divided all organisms into two kingdoms, Plantae and Animalia.