Has anyone ever figured out how many people have ever lived from when man 1st walked the Earth to the present?

Question

We know how many people are in the world today. Do we know how many people have lived on it?

Answer 1

I have always heard that 20 billion homo sapiens have lived. You's think that we'd be up to our arm pits in bones, but apparently not.

Answer 2

The leading demographers in this field estimate that in the past 100,000 years, 120 billion humans (Homo Sapiens) have walked the earth. Considering that the earliest Homo Sapiens bones ever found are 190,000 years old, I would consider that a conservative estimate...

Now, there are nearly 7 billion people on the earth....