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Monday, 7 March 2016

Half-Earth

Half-Earth

by Edward O Wilson

Half of the Earth’s surface and seas must be dedicated to the conservation of nature, or humanity will have no future..
Unstanched haemorrhaging has only one end in all biological systems: death for an organism, extinction for a species. Researchers who study the trajectory of biodiversity loss are alarmed that, within the century, an exponentially rising extinction rate might easily wipe out most of the species still surviving at the present time.
The crucial factor in the life and death of species is the amount of suitable habitat left to them. When, for example, 90 per cent of the area is removed, the number that can persist sustainably will descend to about a half. Such is the actual condition of many of the most species-rich localities around the world, including Madagascar, the Mediterranean perimeter, parts of continental southwestern Asia, Polynesia, and many of the islands of the Philippines and the West Indies. If 10 per cent of the remaining natural habitat were then also removed – a team of lumbermen might do it in a month – most or all of the surviving resident species would disappear.
Today, every sovereign nation in the world has a protected-area system of some kind. All together the reserves number about 161,000 on land and 6,500 over marine waters. According to the World Database on Protected Areas, a joint project of the United Nations Environmental Program and the International Union for Conservation of Nature, they occupied by 2015 a little less than 15 per cent of Earth’s land area and 2.8 per cent of Earth’s ocean area. The coverage is increasing gradually. This trend is encouraging. To have reached the existing level is a tribute to those who have led and participated in the global conservation effort.
But is the level enough to halt the acceleration of species extinction? Unfortunately, it is in fact nowhere close to enough. The declining world of biodiversity cannot be saved by the piecemeal operations in current use alone. The extinction rate our behaviour is now imposing on the rest of life, and seems destined to continue, is more correctly viewed as the equivalent of a Chicxulub-sized asteroid strike played out over several human generations.
The only hope for the species still living is a human effort commensurate with the magnitude of the problem. The ongoing mass extinction of species, and with it the extinction of genes and ecosystems, ranks with pandemics, world war, and climate change as among the deadliest threats that humanity has imposed on itself. To those who feel content to let the Anthropocene evolve toward whatever destiny it mindlessly drifts, I say please take time to reconsider. To those who are steering the growth of reserves worldwide, let me make an earnest request: don’t stop, just aim a lot higher.
I see just one way to make this 11th-hour save: committing half of the planet’s surface to nature to save the immensity of life-forms that compose it. Why one-half? Why not one-quarter or one-third? Because large plots, whether they already stand or can be created from corridors connecting smaller plots, harbour many more ecosystems and the species composing them at a sustainable level. As reserves grow in size, the diversity of life surviving within them also grows. As reserves are reduced in area, the diversity within them declines to a mathematically predictable degree swiftly – often immediately and, for a large fraction, forever. A biogeographic scan of Earth’s principal habitats shows that a full representation of its ecosystems and the vast majority of its species can be saved within half the planet’s surface. At one-half and above, life on Earth enters the safe zone. Within half, existing calculations from existing ecosystems indicate that more than 80 per cent of the species would be stabilised.
There is a second, psychological argument for protecting half of Earth. The current conservation movement has not been able to go the distance because it is a process. It targets the most endangered habitats and species and works forward from there. Knowing that the conservation window is closing fast, it strives to add increasing amounts of protected space, faster and faster, saving as much as time and opportunity will allow.
The key is the ecological footprint, defined as the amount of space required to meet the needs of an average person
Half-Earth is different. It is a goal. People understand and prefer goals. They need a victory, not just news that progress is being made. It is human nature to yearn for finality, something achieved by which their anxieties and fears are put to rest.
The Half-Earth solution does not mean dividing the planet into hemispheric halves or any other large pieces the size of continents or nation-states. Nor does it require changing ownership of any of the pieces, but instead only the stipulation that they be allowed to exist unharmed. It does, on the other hand, mean setting aside the largest reserves possible for nature, hence for the millions of other species still alive.
The key to saving one-half of the planet is the ecological footprint, defined as the amount of space required to meet all of the needs of an average person. It comprises the land used for habitation, fresh water, food production and delivery, personal transportation, communication, governance, other public functions, medical support, burial, and entertainment. In the same way the ecological footprint is scattered in pieces around the world, so are Earth’s surviving wildlands on the land and in the sea. The pieces range in size from the major desert and forest wildernesses to pockets of restored habitats as small as a few hectares.
But, you may ask, doesn’t a rising population and per-capita consumption doom the Half-Earth prospect? In this aspect of its biology, humanity appears to have won a throw of the demographic dice. Its population growth has begun to decelerate autonomously, without pressure one way or the other from law or custom. In every country where women have gained some degree of social and financial independence, their average fertility has dropped by a corresponding amount through individual personal choice.
There won’t be an immediate drop in the total world population. An overshoot still exists due to the longevity of the more numerous offspring of earlier, more fertile generations. There also remain high-fertility countries, with an average of more than three surviving children born to each woman, thus higher than the 2.1 children per woman that yields zero population growth. Even as it decelerates toward zero growth, population will reach between 9.6 billion and 12.3 billion, up from the 7.2 billion existing in 2014. That is a heavy burden for an already overpopulated planet to bear, but unless women worldwide switch back from the negative population trend of fewer than 2.1 children per woman, a turn downward in the early 22nd century is inevitable.
And what of per-capita consumption? The footprint will evolve, not to claim more and more space, as you might at first suppose, but less. The reason lies in the evolution of the free market system, and the way it is increasingly shaped by high technology. The products that win are those that cost less to manufacture and advertise, need less frequent repair and replacement, and give highest performance with a minimum amount of energy. Just as natural selection drives organic evolution by competition among genes to produce more copies of themselves per unit cost in the next generation, raising benefit-to-cost of production drives the evolution of the economy. Teleconferencing, online purchase and trade, ebook personal libraries, access on the Internet to all literature and scientific data, online diagnosis and medical practice, food production per hectare sharply raised by indoor vertical gardens with LED lighting, genetically engineered crops and microorganisms, long-distance business conferences and social visits by life-sized images, and not least the best available education in the world free online to anyone, anytime, and anywhere. All of these amenities will yield more and better results with less per-capita material and energy, and thereby will reduce the size of the ecological footprint.
In viewing the future this way, I wish to suggest a means to achieve almost free enjoyment of the world’s best places in the biosphere that I and my fellow naturalists have identified. The cost-benefit ratio would be extremely small. It requires only a thousand or so high-resolution cameras that broadcast live around the clock from sites within reserves. People would still visit any reserve in the world physically, but they could also travel there virtually and in continuing real time with no more than a few keystrokes in their homes, schools, and lecture halls. Perhaps a Serengeti water hole at dawn? Or a teeming Amazon canopy? There would also be available streaming video of summer daytime on the coast in the shallow offshore waters of Antarctica, and cameras that continuously travel through the great coral triangle of Indonesia and New Guinea. With species identifications and brief expert commentaries unobtrusively added, the adventure would be forever changing, and safe.
The spearhead of this intensive economic evolution, with its hope for biodiversity, is contained in the linkage of biology, nanotechnology, and robotics. Two ongoing enterprises within it, the creation of artificial life and artificial minds, seem destined to preoccupy a large part of science and high technology for the rest of the present century.
The creation of artificial life forms is already a reality. On 20 May 2010, a team of researchers at the J Craig Venter Institute in California announced the second genesis of life, this time by human rather than divine command. They had built live cells from the ground up. With simple chemical reagents off the shelf, they assembled the entire genetic code of a bacterial species, Mycoplasma mycoides, a double helix of 1.08 million DNA base pairs. During the process they modified the code sequence slightly, implanting a statement made by the late theoretical physicist Richard Feynman, ‘What I cannot create, I do not understand,’ in order to detect daughters of the altered mother cells in future tests.
If our minds are to break free and dwell in the far more interesting universe of reason triumphant over superstition, it will be through advances in biology…
Read more here:
aeon.co