The earliest cells were

The earliest jawed verebrate is

The earliest serious efforts to classify the living things were made by

The earliest serious efforts to classify the living things were made by

The earliest jawed vertibrate is

The earliest ancestor in the evolution of horse is "_______".

The earliest classifications were based on

The earliest classifications were based on

[A]: The earliest living organisms were structurally simple. [R]: The earliest living organisms were more complex than present one.

[A]: The earliest living organisms were structurally simple. [R]: The earliest living organisms were more complex than present one.