Hi Peter,
Your latest post under the above thread did appear on
Goanet (Please see the archives). Therefore, I am
posting this reply. Here are my responses to your
points.
Peter D'Souza wrote:
You are incorrect in stating that he assumed a
constant_ growth rate. In fact, this is what he did
say: although it is obvious that the present rate of
growth (2%) could not have prevailed for very long in
the past, it does seem unlikely that the long-time
growth rate could have averaged significantly less
than (1/2)%.
I don't know whether you have a mathematics background
or not. But if you tried to understand the math behind
how you calculate a population change based on a
variable growth rate (i. e. positive growth as well as
negative growth or decline) then you would realize
that the formula used by Morris assumes only a
constant positive growth rate. He also assumes a
constant average growth rate from 1800 to all the way
back to the origin of man. You cannot simply average
positive and negative growth rates, and use the
average in the formula. There are good estimates that
in the last 2000 years there were at least two periods
when there was a negative growth rate (decline).
Nobody has the slightest idea of the directions of
population changes during the 4000 years prior to
that. It is very likely that because of high infant
mortality rates there was 0% growth or negative growth
during some phases of this era.
A real scientist with knowledge about the math
involved would never have attempted to do the type of
calculation that Morris attempted. One cannot derive a
formula for this because one has absolutely no
knowledge of when the population increased and when it
decreased, and by how much, before 200 B.C. It is next
to impossible to derive a realistic combination
formula for variable increases during some variable
periods and variable decreases at other variable
periods. People have written hundreds of papers using
all kinds of mathematical models on this subject.
He seems to believe that one man or couple might have
been in existence 8,000/10,000/6,300 years ago and
that such a man's contemporaries were destroyed. This
seems rational, given his mindset. I'm surprised that
you wouldn't agree but choose to dispute population
growth rate instead.
Please read your first Goanet post on your friend's
argument. What you stated in that post emphasizes the
2% population growth, and mentions that your friend's
estimate is an extrapolation based on that growth
rate, allowing for some natural disasters. This
original argument is similar to that of Morris, and is
mathematically flawed, as shown above. It does not
appear to me to be a genuine scientific argument at
all. Perhaps, you misunderstood what your friend was
saying. If you tell me his name, I could check if he
has published his calculation in any scientific
journal. If he has not published it, it is unlikely to
be a serious, well-researched argument.
I would not use the words real and estimates in
the same sentence.
I mean real scientific estimates as opposed to the
pseudoscientific estimate of Morris.
The same table says that the world population grew at
0% (zero percent) and stayed at exactly 5 million for
a period of 3,000 (three whopping thousand)years. Are
these guys serious? This was before the condom was
invented.
There is nothing unusual about 0% growth rate. I am
sure you know that growth rate is birth rate minus
death rate. If these two rates are equal then you have
zero growth. If the death rate is more than birth rate
then you have a decline or negative growth. In the old
days the death rate was very high, especially the
infant mortality rate. The latter rate was in some
cases higher than 500 per 1000 live births. At this
rate one needed a very high birth rate (more than 8%)
in order to prevent extinction of mankind. This was
very hard to do before large residential communities
were established. People's life expectancy was also
very low perhaps, in the twenties. So the
reproductive life span was also very short.
The people who contributed the data in the table
provided by the U.S. Census Bureau are the worlds
experts on population theory, history and statistics.
They are certainly more knowledgeable and qualified
than Morris. Please do not prejudge them without
reading and understanding their research papers cited
at the bottom of that table. If your friend has
published a paper like that, please let me know. I can
read his and their papers, try to understand and
compare them, and see whose estimates make more sense.
Radiocarbon dating, which depends on the steady
decay of carbon-14, becomes less and less reliable
once the artefact under study gets older than about
16,000 years. is what Dr. Chris Stringer, Natural
History Museum, London,
Radiocarbon dating is only one of many methods used
for dating fossils and artifacts today. There are a
whole bunch of other methods such as potassium-argon
dating, geological dating,
