The Biblical Great Flood killed everyone but 8 ppl and there's now 6.6 bill ppl, what's the growth rate?

Question

The Great Flood occurred ~5000-6000 years ago.

Anyone know what the growth rate per year is?

Answer 1

Roughly speaking, a birth rate of 1.08 children per person would get us to the current population in 6,0000 years.

If we assume that each generation is 20 years, then:

For each pair of surviving adults (lets assume Noah and wife were done):
The number of generations that produce offspring: 300
The number of offspring per pair of adults: 2.16
Since two are required to create an offspring, assume 1.08 offspring per each parent.

If the average person produced 1.08 offspring each: Ending population = 1.08 to the 300th power, or 10.6 Billion (not counting survivors from the previous generation) from each pair of surviving adults.

There were three surviving pairs of adults, so the population would be 31.8 Billion.

This does not account for war, disease, and people who do not reproduce, but it also doesn't account for times of higher birth rate.

Answer 2

What has been the rate in the last 30 years? Take a look at just the US in the 10 year period of 1960-1970:

The Nineteenth United States Census, conducted by the Census Bureau, determined the resident population of the United States to be 203,302,031, an increase of 13.4 percent over the 179,323,175 persons enumerated during the 1960 Census.

Over 13 percent in the US alone and in only 10 years. Pretty impressive.

The Twenty-Second United States Census, known as Census 2000 and conducted by the Census Bureau, determined the resident population of the United States on April 1, 2000, to be 281,421,906, an increase of 13.2% over the 248,709,873 persons enumerated during the 1990 Census.

Again, a 13 percent increase over the 10 year period of 1990 to 2000. The US seems to be increasing steadily about 13 percent every 10 years. The whole number increase is staggering.

The overall increase between 1960 and 2000 was 102,098,731 people for a 36.3 percent increase. That is a huge jump in U.S. population in a relatively short period of time. Especially compared to 6000 years.

Rate of growth based on 13 % increase starting with 8 people:

8
8.32
66.56
532.48
4259.84
34078.72
272629.76
2181038.08
17448304.64
139586437.12
1,116,691,496.96

If the rate of population growth remained constant, the planet would have had a population of over a Billion people within the first 100 years after the flood. This, of course did not happen. As another person answered, rate of growth for the entire world and throughout all of history has not been steady. Its actually been on the slow side.

Although FREEBIRD and I are approaching this math problem from entirely different angles, I believe our end results would end up being very close. At any rate, I think it would be safe to say the scenario of 8 survivors repopulating the planet is entirely possible.

Answer 3

It's not that big of a stretch. The world only hit the one billion population milestone in the year 1804. In 203 years, we've gained 5.6 billion people. That's an incredibly big population growth in an incredibly small length of time.

Answer 4

The rate of population growth has not been constant throughout history.

Answer 5

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