Oh, something else to add,
"Explain why the current population could easily have come from eight people 4400 years ago?"
I assume you mean couldn't.
I answered something about this not too long ago, so, here ya go, what would happen if we applied a constant growth rate... (The place I took the statement from, gave the flood at around 4500, it seems to change a lot
)
I stole this equation, P(n) = P(1 + r)^n from,
http://www.infidels.org/library/modern/dave_matson/young earth/specific_arguments/population_growth.html
I used it to do some interesting calculations.
P = starting population (8 after the flood)
r = rate of growth
n = number of years since flood.
If the flood was 4500 years ago, we need a growth rate of 0.455% or 0.00455 to reach almost 6 billion people today,
So the equation would look like this, 8(1+0.00455)^4500=5,958,006,194 or 6 billion.
This produces some interesting results.
1000 years after the flood, there is a total world population of 749 people.
2500 years after the flood, there is a total world population of 679,180 people.
2600 years after the flood, there is a total world population of 1,069,401 people.
Now whats so amazing about that? Well, 2500 years after the flood, is also 2000 years ago. Around the time when Jesus was said to have been born. Thats right, when jesus was born, there was an Entire world population of 679,180. A little over half a million people populated the Entire world, that includes china, The Americas, the Roman Empire, etc.
Whats so special about 2600 years after the flood, well that would be around 100 AD,
At the zenith of the Roman empire (2nd century A.D.)... ... The population was at least 70 million and may have been in excess of 100 million. The city of Rome itself was home to more than 1 million inhabitants.
http://www.sentex.net/~ajy/facts/romanemp.html
So, the entire world population was apparently in Rome and nowhere else.
If any of this sounds a bit funny, that because it is. The worlds growth rate does not stay a constant number. It is thought that the large world growth rate is based on recent technological advances. In the past, many constraints such as food and disease have kept the growth rate very close to 0, if not sometimes in the negative and thus we would not have over grown the world. We are only now able to out grow the world because we can supply ourselves with lots of food, and rid ourselves of many diseases.