WSI: Demographic Transition Model

To understand technophysio evolution's impact on the global population, we can look at what demographers call the Demographic Transition Model (DTM). The DTM is a model reflecting the experience of Western Europe, extrapolated to interpret anticipated global demographic trends. There are four phases to the DTM:

Stage 1: Death rates (deaths per 1,000 population) and birth rates (births per 1,000 population) vary but tend to balance each other out. Prior to the eighteenth century, this was the near universal story for humanity (although as we have seen, very slow steady growth had been the norm for many centuries before.)

Stage 2: Death rates begin to decline significantly. Birth rates stay constant for a while and then began to drop in a pattern similar to death rates. Though both are declining, the birth rate stays significantly above the death rate for decades (see the dashed line in the chart.) This leads to a significant increase in the population.

Stage 3: Death rate decline begins to slow and level out. Meanwhile fertility rates continue to decline leveling out at a later date. The population continues to experience growth but at an ever slowing rate.

Stage 4: Death rates and birth rates stabilize at or below replacement levels.

Wikipedia provides a chart for 250 years of Sweden's history that illustrates this. Notice the parallel death and birth rates until the beginning of the 1800s. The stages are demarcated for you at the top of the chart.

Stage 2 emerged in Europe because of technophysio evolution. Increased agricultural productivity led to a surplus of food and an improved diet. Improved health and vigor meant more productive people. It reduced the death rate as people lived longer and more productive lives. (Robert Fogel notes that, in England, agriculture improved the caloric intake, but the rapid urbanization created health problems that tended to retard advances in life expectancy until the late nineteenth century.) With improved health, and enough resources to meet basic subsistence needs, people began to address environmental problems like waste elimination and personal hygiene. This lessened the amount of disease and allowed more people to live longer and more vigorous lives.

Stage 3 was when the infant mortality rate (children dying before their first birthday) was noticeably lower. Whereas only four or five children out of eight might have lived to adulthood in the past, now seven or eight children might reach maturity. Fewer children were needed to perpetuate the family, and birth rates declined. Increased industrialization also meant urbanization and a departure from traditional values about family size and the role of women. Women no longer gained as much status from family. They become more educated and literate, often entering the workforce. This led to greater affluence and greater sophistication, creating a better quality of life. People became evermore empowered, and greater demands were made for environmental improvements, safety, and health care.

Stage 4 has seen a stabilization of death and birth rates. Concerns about quality-of-life issues, including environment and health, have risen in importance.

Some believe there may be a stage 5. Eventually, our ability to extend life expectancy will hit a wall, and the death rate will rise a little before stabilizing. With affluence, death rates may begin to increase because of decreased physical activity and increasingly unhealthy lifestyles like overeating. How birth rates will respond isn't known. Whether this is true and to what degree is a subject of debate.

We can extrapolate the DTM to represent global changes with one significant change. The distinguishing feature of the global model is that instead of a relatively smooth transition into declining death rates over decades, death rates plummet quickly. Most developing nations experienced population explosions in the years after World War II when large amounts of aid, vaccines, and technological knowledge were made available. Traditions and customs about family size can't adapt as quickly. Therefore, the gap between birth and death rates (see the dashed line in the graph below) is considerably larger than with the DTM for Western nations. This leads to very rapid population growth.

Here is a chart showing the global birth and death rate from 1950 with projections until 2050:

Another distinguishing feature of the global DTM is the linkage between increases in per capita income and improvements in living conditions. In the Western DTM, growth in per capita income seemed to draw living conditions to higher levels. The global experience has been more a matter of improved living conditions and health, drawing per capita income to higher levels. Aid and technology transfers from the West have essentially shortened the learning curve for other nations following the West through the demographic transition.

It is important to note that the DTM is not without controversy. Looking nation by nation, there is considerable variation in how demographic transitions occur. Still, the DTM is a good standard that helps us frame questions about specific nations and regions. It does seem to capture a sense of the overall global trend.

Next, we will look at the economic growth machine that made the recent rapid population growth while expanding prosperity possible.

(For a scholarly presentation of technophysiological evolution, see The Escape from Hunger and Premature Death, 1700-2100: Europe, America, and the Third World. Wikipedia has a pretty good article on the Demographic Transition Model.)

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Comments

[stevenearlsalmony]

Dear Colleagues:

As humanity's most luminous beacon of truth, science provides us with a last best hope for the survival of life as we know it on Earth. We must make certain that scientific evidence is never downplayed, distorted and denied by religious dogma, politics or ideological idiocy.

Let us not fail for another year to acknowledge extant research of human population dynamics. The willful refusal of many too many experts to assume their responsibilities to science and perform their duties to humanity could be one of the most colossal mistakes in human history. Such woefully inadequate behavior, as is evident in an incredible conspiracy of silence among experts, will soon enough be replaced with truthful expressions by those in possession of clear vision, adequate foresight, intellectual honesty and moral courage.

Hopefully leading thinkers and researchers will not continue supressing scientific evidence of human population dynamics and instead heed the words of Nobel Laureate Sir John Sulston regarding the emerging and converging, human-driven global challenges that loom ominously before humankind in our time, “we’ve got to make sure that population is recognized.... as a multiplier of many others. We’ve got to make sure that population really does peak out when we hope it will.”

Sir John goes on, “what we want to do is to see the issue of population in the open, dispassionately discussed.... and then we’ll see where it goes.”

In what is admittedly a feeble effort to help John Sulston fulfill his charge to examine all available scientific evidence regarding human population dynamics, please give careful consideration to the following presentation and then take time to rigorously scrutinize the not yet overthrown science from Russell Hopfenberg and David Pimentel regarding human population dynamics and human overpopulation.

http://www.panearth.org/GPSO.htm

Please accept this invitation to discern the best available science of human population dynamics and human overpopulation; discover the facts; deliberate; draw logical conclusions; and disseminate the knowledge widely.

Thank you,

Steve Salmony

[Steven Earl Salmony]

Many too many scientists with appropriate expertise as well as demographers and economists everywhere in our time apparently have been rendered apoplectic by presentations of new and evidently unforeseen scientific research of human population dynamics and the demographic transition. These experts have relied upon preternatural thought and phony science to make a seemingly incontrovertible case for the viability of the human species and its current business-as-usual overproduction, overconsumption and overpopulation activities — global overgrowth activities of a distinctly human kind that can be seen overspreading the surface of Earth and that will soon be more generally acknowledged as patently unsustainable on the finite and frangible planet we inhabit.

Absolute global human population numbers have been skyrocketing since World War II. When I was born, 2.3 billion people were alive. In a single lifetime of threescore and ten years (1945-2015) human numbers are fully expected to grow to 7.2+/- billion human beings, an increase of 5+/- billion people.This population growth has been widely believed to be sustainable, at least in large part, because of two critical misperceptions that have been widely shared, consensually validated and allowed to stand unquestioned. Ruinously, predominant ideology has been deliberately confused with and presented as science. Recent unacknowledged scientific research indicates with remarkable simplicity and clarity that human population dynamics is essentially similar to the population dynamics of other species and that the traditional demographic transition model indicating population stabilization and an end to population growth soon is pseudoscientific, fatally flawed and utterly misleading. Fundamental mistakes have been made but experts have consciously refused to perform their duties to science and humanity by making necessary corrections.
Self-proclaimed population experts certainly are not stupid, and yet they appear to act as if they are ‘playing stupid’. Perhaps they been unfortunately influenced by "The Powers That Be" (TPTB) just the way politicians have. In their foolhardiness, arrogance and avarice and by their lust for privilege, power and the concentrated wealth from which power and privilege are derived, TPTB have claimed ownership of the mass media. Global communications have become governed by what is economically beneficial, politically convenient, socially suitable, religiously tolerable and culturally contrived. The family of humanity has been duplicitously misguided and deceitfully duped by overly-educated, absurdly enriched sycophants of rich and powerful greedmongers who have been undermining and perverting science. The shared ideology of TPTB and their many minions leads to their imperious denial of scientific research that not only presents inconvenient truth but also exposes the ruse underpinning a non-negotiable but unsustainable way of organizing human civilization on our watch. One of many pernicious effects of this situation is the willful denial of the best available scientific research of subjects like human population dynamics and the demographic transition. Resulting misunderstandings have been decisive in paving the way for a civilization nearing its collapse. Civilizations have crashed before, but never has the demise of a civilization put at risk future human well being and the Earth as a fit place for human habitation. Should this perspective be somehow on the right track, then we could be witnesses to a colossal failure of nerve as well as to a determinative loss of capacity to do the right things, according to ‘the lights’ and scientific knowledge each of us possesses.

If human population dynamics is essentially common to the population dynamics of other species and, consequently, if food supply is the independent not the dependent variable in the relationship between food and population, then a lot of what has been reported could be distractions that serve to dismiss rather than disclose vital but unwelcome science of what could somehow be real regarding the human population and, more importantly, why our behavior is so utterly destructive of everything we claim to be protecting and preserving. It seems to me that if we keep engaging in and hotly pursuing worldwide overproduction, overconsumption and overpopulation activities, distinctly human activities that cannot be sustained much longer on a planet with size, composition and ecology of Earth, then the human species is a clear and present danger on our watch to future human well being, life as we know it, and environmental health. If we can see ourselves to be 'the problem', then it is incumbent upon us to bring forward the best available evidence from science, especially when that evidence happens to relate directly to why we are pursuing a soon to become, patently unsustainable (superhigh)way of life. A tip of the hat is due Rachel Carson for her original awareness of the 'superhighway'. Should humankind emerge from 'the bottleneck' E.O. Wilson imagines for us in the future and somehow escape the precipitation of our near-term extinction, how are those survivors to organize life sustainably and not repeat the mistakes we are making now... and have been making for a long time? Without knowledge of why we are doing what we are doing, every one of us is forever trapped in an eternal recurrence of unsustainable life cycles, I suppose.

PS: Rachel Carson's quote,

We stand now where two roads diverge. But unlike the roads in Robert Frost's familiar poem, they are not equally fair. The road we have long been traveling is deceptively easy, a smooth superhighway on which we progress with great speed, but at its end lies disaster. The other fork of the road—the one "less traveled by"—offers our last, our only chance to reach a destination that assures the preservation of the earth.

[Michael W. Kruse]

Thanks for your input. I'm not as pessimistic as you seem to be.

First, global population grow is decelerating. In fact, a chief concern is that populations in advanced nations seem to be stabilizing with fertility rates well below replacement. There is concern that by the second half of the century there depopulation will set in, causing a different set of problems.

Second, if you multiply current consumption dynamics per capita by a growing population, then certainly growth is unsustainable. But consumption dynamics do not stay constant. There is constant innovation and adaptation. That is what I think is missing from your analysis.

Power consuming devices continue to become more efficient. Renewable energy, still in its infancy, is making leaps and bounds. Vast portions of the planet are underutilized in food production because of long outdated farming techniques. Then there is the promise of GMOs and innovations like vertical farming. With regard to non-renewable materials, nearly everything we us today can ultimately be made of from renewable materials. Nanotechnology holds the promise of being able to breakdown matter at the molecular level and reassemble it into other materials.

As a type of energy or matter begins to become less accessible, its price will rise relative to substitute materials. That makes the alternatives more attractive to investors and entrepreneurs. Eventually, everything can be from renewable alternatives.

The choice is not between economic growth and saving the planet. The choice is about achieving economic growth over the coming decades in ways that both sustain growth and the planet.

Natural gas and nuclear energy are transitional alternatives for the next several decades, creating time for our technologies to evolve beyond these sources.

In short, taking today's circumstances and projecting them, unaltered by innovation, into the future is a critical mistake. I'm not suggesting there is no need to advocate for change but were are not in situation that warrants alarmist responses.

We need to growth all of earth's population out of poverty, but in sustainable ways. Hans Rosling sums it up as well as anyone I know in this short video:

http://www.youtube.com/watch?v=jbkSRLYSojo