Well the Creationist would say that 4400 yrs ago after the flood occured the earths population was 8, that be Noah and the rest of his crew. They say that 4400 yrs is more then enough to bring the population to where it is today.
Do you realise that the assumptions made in order to justify that particular assertion contradict not only recorded history but even the numbers given in the Bible itself?
Now if that be the case, what would the population be like if we had 200,000 yrs to populate the earth?
Modern man has been on the Earth for 200,000 years and the population is what it is now, so I'm not sure how to understand your question. Do you want a discussion of our estimates of population through time? The causes behind its variation? What?
Edited by Mr Jack, : Cut up quote more coherantly.
However, if we can agree the science of the human genome correct, we can all trace our origin to some guy living in Africa only 60,000 years ago.
"Y-Chromosone Adam" lived around 60,000; but that is not our most recent common ancestor, they lived much more recently. Just 7000 years ago, according to Rhode (other estimates put them between 5000 and 15000 year ago, and the most recent ancestor of all Europeans (and white americans) around 1000 AD.