What is the longest eon, when single-celled organisms ruled the Earth?
Proterozoic
Anthropocene
Phanerozoic
Cenozoic
The correct answer is Proterozoic.
What is the longest eon, when single-celled organisms ruled the Earth?
Proterozoic
Anthropocene
Phanerozoic
Cenozoic
The correct answer is Proterozoic.