As of 2008, the average human birthrate across our planet was about 2.6 children per woman. However, hidden within this global average lay the substantial disparity between an average birthrate of about 1.6 children per woman in the developed nations of the world and an average birthrate of about 2.8 children per woman throughout the less developed nations.
Yet, dwarfing even that variability is the extreme disparity in birthrates within those less developed nations. That is often much more drastic, with the average birthrate of the poorest fifth of a population soaring to 6 or even 7 children per woman, while the average birthrate of the most affluent fifth of that same population may be only 2 children per woman.
It is therefore clear that upward social and financial mobility for all is key to lowering average birthrates to truly sustainable levels. Thus, sustainability in a global perspective requires the increased availability of clean water, ample food, education, jobs, and human rights and freedoms within societies. We have a great and daunting task before us.
That portion of the African continent lying south of the Sahara Desert may present sustainability’s greatest challenge. Comprised of most of the world’s poorest and least developed countries, it is home to roughly 1 billion people, and is projected to bear a total of 2 billion humans within the next 40 years. Supporting this population of from 1/5th to 1/7th of the world’s total is but 1/11th of the planet’s freshwater, and even that is not equitably distributed across the land. Political instability, war, poverty, disease, social upheaval, mismanagement, corruption, opportunism, drought, and adverse aspects of migration and urbanization have, over the last 30 years, driven life expectancies throughout this region from the 50s-to-70s to only the 30s-to-50s.
And, while the poor and disadvantaged youth of Sub-Saharan Africa may be, in effect, our poster child for the challenge of sustainability, that child is by no means alone. Many of the young of the Indian subcontinent, Indonesia, China, South America and the Middle East, if unaided, face no less bleak futures.
So, what can architects and designers do? We must drive advancements in design technology and materials development down to a pervasive, low-cost level. We must create elements of architecture, building and appliances that can contribute incrementally to a sustainable and more humane world. Already substantial invention is at work — simple dry latrines, modest water pumps, construction using found and recycled materials, low-cost solar devices — all of which do their part in steering our world to sustainability.