Will the Sun set on the human race?: Can Homo sapiens survive - or is it doomed to extinction, a fate known to have overtaken up to 99 per cent of all life forms?
Credit: iStockphoto
On a cold autumnal day they came from around the country to 'the Dome' to talk about the approaching darkness: scientists, economists, philosophers, ethicists, botanists, ministers of religion, historians and the odd politician. Many were the elders of their professions, having known lives rich in learning and enquiry. But there were also young students present, full of energy and anticipation.
More than 150 people gathered at the Australian Academy of Science's distinctive Shine Dome in Canberra. With an average age of at least 50, this congregation of the intelligentsia had some 7,500 years of experience to draw on.
And they were gathered in this shrine of science to discuss one question: can Homo sapiens – the primate species that has evolved to dominate the planet – survive? Or is it doomed to extinction, a fate known to have overtaken up to 99 per cent of all life forms?
In earlier times and other places, it's likely that society's elders have similarly gathered to discuss such big issues. If the best information around suggests your society may be about to wither, perhaps even disappear altogether, surely it is up to the best and brightest to ask some hard questions.
Humans have been extraordinarily successful. When the British made landfall at Sydney Cove in 1788 and began colonising Australia, the world's population was about 750 million. The total today is nearly eight times as many; there is hardly a place where humans haven't been … and nowhere they don't influence.
Thanks to industrialisation, our hunger for resources and the sheer number of people, humans have an immense impact. They outstrip every other species in demand for energy and resources, to the point where their impact on the biosphere arguably threatens our own long-term viability.
The world is in the sway of a dangerous illusion. Most leaders, officials and institutions behave as if the human enterprise is somehow remote from the environment; as if human expansion can go on forever; as if the Earth's resources and energy were limitless. And yet, we know this is not the case. We know many complex civilisations, successful and advanced, have nevertheless collapsed. Ours could too.
The worldwide population is expanding by about 75 million people a year. Even given that population growth rates are declining, United Nations projections put the global population at almost 8 billion in 2025.
Humans have already used nearly a third of all available land area – some 3.8 billion hectares – in agriculture or built-up areas. Most of the remainder is too dry for agriculture. Global grain production, currently 1.84 billion tonnes annually, will need to increase by about 40 per cent to meet demand in 2020.
While demand is going up, our capacity to meet that demand is under a growing cloud. Human-induced soil degradation has been getting worse since the 1950s. About 85 per cent of agricultural land contains areas degraded by erosion, salination, compaction, and other factors.
It has been estimated that soil degradation has already reduced agricultural productivity by 15 per cent in the past 50 years. In the past 300 years, the rate of topsoil loss was 300 million tonnes per year; in the past 50 years that rate has more than doubled to 760 million tonnes per year.
On top of this, if current water consumption patterns continue, half the world's population will live in water-stressed river basins by 2025.
What it all adds up to is hotly debated, but for many people it looks a little like Easter Island (see Civilisations: why they fail, Cosmos Online): that we are driving headlong into a crisis we seem unable to see. We're getting to the end of the trees, and still we keep chopping. As if nothing was wrong. Time for the elders to meet.
Can Homo sapiens survive? The elders' deliberations at the conference, organised by Manning Clark House, a cultural and academic centre in Canberra, were about science and ethics. Can science save us from ourselves, or is it the root of the problem?
"Will the unintended products of the science and technology revolution of the past 200 years, greatly intensified during the past 60 years, lead to the extinction of the human species?" asked Australian virologist Frank Fenner in the opening address.
Fenner definitely qualifies as an elder of science. Not because he's advanced in years (though he is 90), but because he has been a true warrior of science. He is one of the world's foremost microbiologists, having carried out pioneering work on malaria, tuberculosis and myxomatosis (and being one of only three people to inject themselves with the rabbit-controlling myxoma virus to demonstrate its safety to humans).
In a stellar career, he is perhaps best known for his pivotal role in the successful campaign to eradicate smallpox from the planet. How many people can claim they were instrumental in defeating a global scourge? Indeed, such is the prestige of the man that this particular gathering of elders was held in his honour.
And is he worried? He sure is. "How did humans, in the past 100 years, multiply from some 1.7 billion to over 6 billion now and, if there are not awful disasters, will reach 9 billion within the next 50 years?" Fenner asked.
"The answer, I fear, is that the fantastic advances in science and technology in general, and medical science in particular, reinforced by religious beliefs, are responsible for the idea that the human species is unique – not only in being different in kind from all other animals, because of its acquisition of culture, but in being excluded from Darwinian natural selection. As a person whose life's work has been to advance medical science, thus driving the population explosion and the continuing increase in life expectancy, this is not a comfortable thought."
But it's more than just an issue of science increasing our population. It's also a matter of our technology allowing us to consume the planet's resources at an ever-accelerating rate, he said. Fenner went on to talk about the world's 'growth fetish' as an ideology in which economic growth must go on spiralling upward forever, heedless of what the planet can actually support. "We must radically change our behaviour," he implored.
"We must overcome the growth fetish and somehow use our current affluence to attack poverty. And we don't have much time."
Following Fenner was a stream of distinguished representatives from other fields, putting forward their own insights on science and the question of survival of the species. And the same themes continually emerged: science is powerful and has enabled an overconsumption of the planet's resources; we need to make a major change; and that change needs to happen soon.
"There are about 1,000 times as many people to be fed as there were before the introduction of farming about 450 generations ago," said Stephen Boyden, a worldwide authority on human ecology. "This places enormous continuing pressures on the food-producing ecosystems of the biosphere.
"During the past few generations, there has been a massive intensification of resource and energy use and technological waste production by humankind. As a species, we are now using about 12,000 times as much energy every day as when farming started. And we're discharging into the environment about 12,000 times as much greenhouse gas, carbon dioxide, as well as vast amounts of other environmental pollutants."
Boyden's term for this alarming growth is "evermorism" – a term he defines as an ideology requiring 'evermore' levels of consumption and waste. "It's environmentally absurd," he said.
Then an earth scientist put the historical performance of Homo sapiens in a global geological context. "Throughout the 20th century, evidence mounted of an exponential loss in habitat and disappearance of species," said Andrew Glikson, an earth scientist at Canberra's Australian National University (ANU) and one of the organisers of the conference. "This is comparable with mass extinctions recorded in geological history at the end of Ordovician, Devonian, Permian, Triassic and Cretaceous periods."
"This current extinction is different because it is caused by us," said Glikson, who added that it might be appropriate that Homo sapiens be renamed 'Homo biocidus' for its outstanding record in wiping out other forms of life.
John Chappell, another earth scientist at the university, took up the theme of extinction with a particular focus on corals.
"Coral are my exemplars," said Chappell, with a sad gleam in his eye. "These reef-builders have, over hundreds of thousands of years, weathered large, rapid changes of sea level and climate but are in widespread decline owing to rising temperatures, sediments and carbon dioxide."
Chappell's team discovered the correlation between the 1997 Indonesian wild fires – caused by unsustainable logging practices – and massive and deadly algal blooms in nearby coastal waters. Apparently, nutrients in the smoke served as a fertiliser for the algae. The algal bloom killed all the fish and coral reef over a stretch of some 400km. Examining a record of fossilised corals, Chappell's team found this red tide had been the worst in some 7,000 years.
But declines in coral reefs aren't restricted to Indonesia: they're happening all around the planet, and it's the impacts of human activity that are behind their retreat, he said. In the Caribbean, for example, there has been an 80 per cent decline of coral in recent decades. Corals have been described as our 'canary down the mineshaft'. If so, maybe we should be taking heed.
If science helped us into this mess, then surely it will also offer a way out? We pride ourselves as being the cleverest species that ever strode the planet.
We've conquered land and sea and space; learnt how to build materials from their basic atoms; developed ways of curing or preventing most of the diseases that can kill our species; searched back almost to the beginning of time; discovered and unlocked the primordial forces that hold atoms together. If can we make these incredible technological and scientific advances, we are surely bright enough to work out just how to maintain a highly developed civilisation and not take our own species to extinction?
Well, maybe we're not so clever: most of our technological advances are applied heedless of the cost to future generations. Depletion of fossils fuels, nutrient build-up in our land and water systems and unrestrained growth in greenhouse emissions – all are consequences of our failure to acknowledge and account for the impacts of our technology: we have become hooked, like a junkie to heroin, incapable of breaking away.
We are addicted to energy-sucking air conditioners, our petrol-guzzling cars, and all the gizmos and gadgets that the electricity drives, and which require mountains of coal to be burned every minute of the day.
Some people think money makes the world go around. Others, such as ANU geologist Prame Chopra, know better. "Energy makes the human world go around," said Chopra. "It's the stuff of life. At every level of our lives, from individual cells to the machinations of our national and international economies, energy is the driving force and one of the prime objectives."
So, we're hooked on it, but rather than explore alternative or more sustainable ways of producing energy, we're locked into a dependence on the easy stuff: fossil fuels. And if you're wondering where our escalating fuel prices will end, Chopra recommends you look to China.
The one variable that has closely and consistently shadowed the oil price over the last five years has been the level of oil imports to China; and China's thirst for oil is rapidly escalating. "It took 38 years for China to acquire its first million cars and only three years for the second million." said Chopra.
"If in the coming years it's business as usual, China will be the world's biggest emitter of greenhouse gases by 2020."
But regardless of how high the price of oil goes, the biggest cost we'll be paying for this addiction to fossil fuels will be climate change, said Michael Raupach of the Earth Observation Centre, part of the CSIRO. Its impacts are real, from sea-level rises to temperature increases; they are global and inescapable, and we know that human activity is behind the dramatic increases in greenhouse gases, he said. Raupach pointed out the enormous inertia in the climate system, so that we simply can't wait until the full extent of climate change becomes obvious before we do something about it.
Is the solution to our overtaxed Earth more of the same? More technological fixes? We split the atom more than half a century ago and tapped into untold power. Some scientists argue our next big adventure will be manipulating the genome: that a new age of biotechnology lies before us.
But others suspect genetic engineering is more dangerous than we imagine. "Physicists lost their innocence with Hiroshima and Nagasaki in 1945. Now it's the turn of biologists," cautioned Geoff Davies, an ANU geophysicist with a deep understanding of the perils of playing with complex systems.
"Genetic engineering is not just an extension of traditional breeding methods, it is 'super fire': a tool with unprecedented power to meddle with the fundamentals of the living world. Multicelled organisms have been developing for hundreds of millions of years, and the way they are is no accident. Life, ageing, death and breeding are cyclical. Barriers to crossbreeding ensure the viability of species and ecosystems. The complex relationships within ecosystems support every component species and individual."
Mass extinction, runaway genetic engineering and ecological shutdown: enough to keep you pondering. At least we no longer have to worry about the Bomb, or so we thought. Then Des Ball addressed the conference.
According to Ball, one of Australia's leading defence analysts, the prospects of a nuclear war between the U.S. and Russia are now fairly remote – although between them they still possess more than 15,000 nuclear weapons. "Nuclear war is in fact more likely between India and Pakistan than it ever was between the U.S. and the Soviet Union during the Cold War," he said.
On six occasions in the past few years, nuclear weapons have been a factor in conflicts between the two populous neighbours. Scenario planning undertaken in 2002 suggested an exchange of just two dozen 25-kilotonne nuclear weapons would result in as many as 35 million deaths.
"In the longer term, a nuclear war between India and China would be much more catastrophic," said Ball. "By 2015, China might have more than 1,000 nuclear weapons and India about 300. A nuclear war between them might then involve an exchange involving up to perhaps 500 warheads."
Fatalities in this situation would amount to some 250–300 million on each side. Unfortunately, these new nuclear powers have the weapons, but not the same 'assured second-strike capabilities' that the USSR and the USA had during the Cold War. This capability meant that with many weapons scattered around the country in underground silos and a series of layered, multiple command-and control systems, your enemy is aware you could retaliate if they struck first.
That makes your enemy think before starting anything. But India and China may have no such capability and, without it, "the pressures for pre-emptive or decapitation strikes can become compelling," said Ball.
The meeting of the elders carried on over two grey days. Most members of the audience were aware of the seriousness of the matters being discussed, and largely in agreement with the speakers. But there was a growing disquiet. There was so much that seemed so wrong, and yet the world carried on as if nothing was amiss. Where was the radical change to come from?
Now and then, there were shouts from impassioned audience members denouncing human overconsumption, or the failure of our political system to tackle these problems. But their cries, and the smattering of applause that sometimes followed, had a lonely, impotent ring to them. Is this how it will all end for us – with a whimper? Like the Easter Islanders, will we slide headlong into oblivion, knowing we could have done something – but didn't?
So indeed, back to the question of the conference: can we, as a species, survive? If not, what will knock us off? Will it be ecological breakdown or the Bomb, a new ice age or a greenhouse effect; will we simply run out of food or energy? Or maybe it will be a bit of all of these?
"I think Homo sapiens will survive," said Fenner. "But from about 2050, it'll be pretty tough going."
Raupauch cautioned: "We have just two more generations, at most, to fix the problem with our climate systems. We are aware of what we need to achieve to survive in the longer term, but the big trick is to identify the next steps."
"I see a glimmer of hope," observed Boyden. "Humans can display enormous ingenuity when motivated. But the collapse of our civilisation is inevitable unless there are dramatic changes in the worldview, assumptions and priorities of the dominant cultures of human society. At this meeting, the people in attendance are well informed, but we are not representative of the broader community. Therefore, the most urgent task is education and communicating these ideas, both within Australia and worldwide."
How do you produce the scale of radical changes needed? Clive Hamilton, director of the progressive think tank, the Australia Institute and one of the few economists present at the meeting, believes that the disease of 'affluenza' – an affliction of chronic overconsumption that has infected so much of our society, isn't easily cured. "Twenty per cent of people may change because they see the costs of this overconsumption," he said. "But most will probably choose to go down consuming."
Chopra believes the changes needed will only happen following some huge demonstration of what's coming for the planet. "We need an incontrovertible collapse as a wake-up call, like a massive crack in the Icelandic ice cap," he said.
How did the Easter Islanders deal with the increasing probability of ecological collapse back in the 16th century? As their cultural trajectory had them hurtling towards a barren future in a treeless land with no prospect of escape, surely some of their elders were advocating the need for the entire society to adopt radical change? If so, then they were either ignored … or they spoke up too late.
David Salt is a science writer in Canberra, and a former editor of Newton and The Helix.
