What was the first life form on Earth?
What, today, is the most abundant life form on Earth?
What is the oldest living organism on Earth?
What was the first life form on Earth?
B: Define life.
What, today, is the most abundant life form on Earth?
B: Protozoa.
What is the oldest living organism on Earth?
B: Google "Humungous Fungus"
And yes, I'm serious.