The following article is re-posted from the blog: The foolish pursuit of Economic Growth.
Brishen Hoff
Unless earth is hit by a massive meteor, we will be vastly overpopulated for well over 40 years even if everyone is immediately sterilized. This means we will experience a die-off and more species extinctions. I suggest that earth’s sustainable population is only 2,500,000 (1).
Yes, that’s million, not billion. If you think that is extremely low, think again. That is over 7 times the current population of all great apes (chimpanzees, bonobos, gorillas, and orangutans) combined! That is 10 times earth’s population that persisted for the majority of our 2 million year human history! Perhaps if you think 2.5 million is too low for a global sustainable human population you are underestimating:
A) the scale to which we convert land into food using non-renewable fossil fuels
B) how much we’ve already permanently degraded earth’s carrying capacity
C) how unsustainable our current “6th Mass Extinction” is
My estimate of 2.5 million as a sustainable global population is based on a viable hunter-gatherer population 10,000 years ago (when our numbers forced us into the low EROEI lifestyle of agriculture) of 5 million. I adjusted 5 million to 2.5 million because I believe our carrying capacity has been permanently degraded by at least 50%. There aren’t as many species left and much of our land is now polluted, deforested, paved, infertile, etc. I think it is important to have a low enough population that a high EROEI hunter-gatherer culture is viable for all who desire it.
How badly we are overpopulated in the next 40 years depends on what we do. Quinacrine sterilization has great potential and offers real hope for a brighter future. (2) Without harming anyone we can ensure maximum speed of population decline (which we already know is slower than desired) using Quinacrine sterilization which would have to be mutually-agreed upon by the majority and enforced just like other laws (eg: everyone has to pay taxes).
Assuming average life expectancy is 80 and equal age and sex distribution…
What is a population estimate in 40 years if all females from now on have 0 children during their reproductive lives?
Current population is 6.7 billion.
If nobody reproduced for the next 40 years, our population would be 3.35 billion because half would have exceeded life expectancy.
What is a population estimate in 40 years if all females from now on have 1 child during their reproductive lives?
Average age for menopause is 51 years (3,4).
Average age for menstruation is 13 years (5).
One Peruvian female gave birth at age 5 and one Indian female gave birth at age 70. (6,7)
Biologically, the theoretical range of fertility is 65 years but the practical range of fertility is more like 38 years.
51 + 13 = 64
64 / 2 = 32 (average age of fertile female)
We will assume that the average age that each woman has her one child is 32 (generation time).
How many already existing females will be of child-bearing age within the next 40 years?
51/80 = 63.75% of 3.35 billion = 2.135625 billion
How many already existing women are already of child-bearing age?
38/80 = 47.5% of 3.35 billion = 1.59125 billion
How many already existing females are not yet of child-bearing age?
13/80 = 16.25% of 3.35 billion = 0.544375 billion
How many of these 1.59125 billion women have already had one or more children?
Let’s assume 80% worldwide. (Based on footnote C)
Therefore, 20% of 1.59125 billion = 0.31825 billion women of child-bearing age who already exist but have not yet had their one child. They already average 32 years so will have their child within 1 year.
0.544375 billion more females will each be having one child. These females are from age 1 to 13 averaging 7 years today and will reach 32 years in 25 years when they give birth. 32 years later, or 57 years from today, their female offspring will add another 0.544375 billion / 2 = 0.2721875 billion babies to the earth.
0.31825 billion + 0.544375 billion = 0.862625 billion children born by women who are alive today
0.31825 billion babies were born within a year of today so half of them (the 0.159125 billion females) will each have one child in 32 years. These 0.159125 billion babies are the grandchildren of the 0.31825 billion females averaging 32 years today.
Of the 0.544375 billion babies born 25 years from today by the females who average 7 years today, 0.2721875 billion are female babies but these babies will not quite have their babies within the next 40 years. Their babies will be born 57 years from today.
Since the elder 50% of the population will be dead within 40 years…
3.35 billion + 0.862625 billion + 0.159125 billion = 4.37175 billion people
Therefore, if all females from now on have a total of 1 child during their reproductive lives, the earth’s population would decline from 6.7 billion to 4.37175 billion.
The difference between choosing 1 child per female instead of 0 child per female amounts to over 1 billion additional consumers over 40 years.
I think the choice is clear. 0 child per female law is the only sane course of action to take over the next 40 years.
Since 3.35 billion and 4.37 billion are both over 1000 times a sustainable world population, I am in favour of no new babies for the next 40 years.
REFERENCES:
1) http://ecologicalcrash.blogspot.com/2008/11/how-to-live-in-sustainable-world.html
2) http://home.alltel.net/bsundquist1/qs.html
3) http://www.peelregion.ca/health/hsexual/htmfiles/masmeno.htm
4) http://en.wikipedia.org/wiki/Menopause
5) http://en.wikipedia.org/wiki/Menarche
6) http://en.wikipedia.org/wiki/List_of_youngest_birth_mothers
7) http://en.wikipedia.org/wiki/List_of_oldest_birth_mothers
FOOTNOTES:
A) http://www.msnbc.msn.com/id/17937795/
B) http://www.thesun.co.uk/sol/homepage/woman/real_life/article64716.ece
By CANDICE GIFFORD
Published: 26 Sep 2006
NICKI DEFAGO and husband Jim Scobie were on an extended honeymoon in Central America when they decided never to have children.
Watching the sun set on the Mayan ruins of Mexico’s Chichen Itza, they realised that if they became parents they would not have the time or money to pursue that kind of lifestyle.
It is a controversial choice and the couple have had to fight a lot of prejudice over it.
Nicki, a 40-year-old journalist, says: “Having made my decision, I noticed there were hundreds of books on having a baby but nothing out there saying having children is not for everyone.
“That’s why I decided to write a book (Child Free And Loving It! by Nicki Defago, Vision Paperbacks, £10.99) about the pleasures of child-free living.
“People are constantly telling me I’m being selfish or that I will change my mind. Some people say, ?But that’s what women are for.’
“A man at a party once told me I was abnormal. I pointed out that a lot of men don’t have children. He said, “Yes, but men can do other things.” As if women can’t!“
C) http://www.iht.com/articles/2008/08/19/america/fertility.php
http://www.nytimes.com/2008/08/19/us/19census.html
D) http://www.washingtonpost.com/wp-dyn/content/article/2006/11/24/AR2006112400986.html
Brishen Hoff is a retired computer programmer. He lives on a rural homestead in Canada with his father and enjoys their own nature preserve. He also serves as President of Biodiversity First.