1,000 Times Too Many Humans? Jennifer Viegas, Discovery News
Nov. 25, 2003 - A study that compared humans with other species concluded there are 1,000 times too many humans to be sustainable.
The study, published in the current Proceedings B (Biological Sciences) by the Royal Society, used a statistical device known as "confidence limits" to measure what the sustainable norm should be for species populations. Other factors, such as carbon dioxide production, energy use, biomass consumption, and geographical range were taken into consideration.
"Our study found that when we compare ourselves to otherwise similar species, usually other mammals of our same body size, for example, we are abnormal and the situation is unsustainable," said Charles Fowler, co-author of the paper and a lead researcher at the National Marine Mammal Laboratory, a division of the National Oceanic and Atmospheric Administration.
Fowler likened the concept of normality to body temperature, where measurements can fall above or below the accepted average. A temperature of 105 degrees F, for example, is considered abnormal and unsustainable. In his paper, Fowler and colleague Larry Hobbs argue that the human population, now measured at approximately 6 billion, falls outside the range of sustainability, which puts us at risk.
"Collectively the risks reflect the complexity of biotic systems, but specifically (they) include things like the risk of extinction, starvation, and disease," Fowler told Discovery News.
Such pathologies can be alleviated, according to the paper, but changes would have to be profound and widespread.
"It is probably not unrealistic to say that nothing less than a full paradigm shift is required to get there from here," Fowler explained. "It requires changes in our thinking, belief systems and understanding of ourselves."
William Rees, professor of community and regional planning at the University of British Columbia, disagrees that humans are abnormal and said, "I would use the term 'unusual' instead."
Rees explained that humanity has been inordinately successful. Unlike other species, humans can eat almost anything, adapt to any environment and develop technologies based on knowledge shared through written and spoken language.
Rees, however, said that we may be "fatally successful." He agrees that industrial society as presently configured is unsustainable.
"In the past 25 years we have adopted a near-universal myth of 'sustainable development' based on continuous economic growth through globalization and freer trade," Rees wrote in a recent Bulletin of Science, Technology, and Society paper. "Because the assumptions hidden in the globalization myth are incompatible with biophysical reality the myth reinforces humanity's already dysfunctional ecological behavior."
Rees believes unsustainability is, in part, driven by a natural predisposition to expand, in the same way that bacteria or any other species will multiply. He claims that it is an old problem, reflected in the collapses of numerous civilizations, such as the early human population at Easter Island.
Rees told Discovery News that there is a way out, but he wonders if we will take it.
Rees added, "It would be a tragic irony if, in the 21st century, this most technologically sophisticated of human societies finally succumbs to the unconscious urgings of fatally self-interested primitive tribalism."