For the second time in five years, scientists
are warning about declining human sperm counts. (I wrote about this
issue in "Declining
sperm counts: Nature's answer to overpopulation?" early last year.)
Besides confirming the results of an
important 2017 study, the authors now note an acceleration in the
decline of sperm counts. In other words, whatever is causing that decline
is getting worse. The rate of decline has doubled since 2000.
It's important to remember that when the fertility
rate declines below replacement—currently 2.1 births per woman in
so-called developed countries—populations shrink. This may not be a bad
thing at first since overpopulation and overconsumption are huge barriers
to building sustainable societies. But there comes a point when if
fertility rates don't level off and then rise to replacement, extinction
become a possibility.
That is apparently where we are heading as a global society. A phenomenon
as complex as fertility cannot be explained by one or even a few factors.
There is, for example, what is called the "demographic
transition," a theory which posits that the size of households
declines as societies industrialize. This could result from many factors
such as the empowerment of women (to control their own fertility);
improvements in public health and nutrition that reduce mortality among
infants and children (making parents less likely to have many children
because some are likely to die); the rising cost of raising and educating
children; and cultural factors that lead parents to want to have more time
for themselves.
But some scientists have been pointing to other factors associated with
industrialization, namely, the widespread dispersion of toxic chemicals in
the environment that can adversely affect fertility; the increasing use of
pharmaceuticals; the ubiquitous presence of plastics in the environment
and human bodies; smoking; poor diet; and obesity (which itself may be a
product of endocrine disruption caused by environmental toxins).
The shocking conclusion of the 2017 study was that if the rate of decline
in sperm counts observed then continued, those counts would reach zero by
2045. This latest study concludes that we as a society may be moving even
more quickly toward that destination.
Given the monumental increases in world population since the beginning of
the industrial revolution, it is hard to imagine a collapse in human
population that might be almost as swift. And, yet that is what population
biology and this latest sperm count study suggests. If the suspects listed
above are major reasons for the decline, it's hard to see how
the monied interests behind them would allow much to be done.
ABOUT THE AUTHOR
Kurt Cobb is a freelance writer and communications consultant who writes frequently about energy and environment. His work has appeared in The Christian Science Monitor, Resilience, Common Dreams, Naked Capitalism, Le Monde Diplomatique, Oilprice.com, OilVoice, TalkMarkets, Investing.com, Business Insider and many other places. He is the author of an oil-themed novel entitled Prelude and has a widely followed blog called Resource Insights. Point of contact: kurtcobb2001@yahoo.com.
|
![[groups_small]](groups_small.gif)