Human Extinction: How it Might Happen?
Human extinction, not exactly the nicest thing to imagine is it? It also seems a very strange thing to consider, given the fact that we are the most abundant large mammal on the planet. Today, our population stands at 7 billion and continues to rise. However, as that already bloated figure increases, so greater demand falls on to the natural world to supply with us the resources that make our lives possible. Its already accepted among most scientists that we are in the midst of a mass extinction, that may ultimately end with our own.
We often forget that we are part of the natural fabric of the planet,rather than set apart from it. I often hear talk of man vs. nature, but such talk is damaging because it makes our existence seem like some sort of contest or game. But the game, is simply one we cannot win, purely because nature and man are not separate, we are one and the same. Human extinction is not some far flung fantasy dwelling within the realms of science fiction, it's a very real concept, although predicting when it will happen is more or less impossible. But what we can do is speculate as to how it might come about. Its not a nice thing to do, but I believe that it's necessary purely to teach us humility before nature, and remind ourselves of who we really are, where we came from and where we intend to go from here.
Explaining Climate Change
More on Climate Change
By this end of this century, it is estimated that the amount of greenhouse gasses being pumped into the atmosphere will be more than double the current amount, a fairly reasonable estimate, when you factor in the incredible growth of countries such as China and India. The result of all those extra emissions will be an increase of two degrees in the average global temperature, meaning that Earth will be at its warmest point in the last 1.5 million years. Two degrees may not sound much, but bear in mind that's the average, certain places such as Antarctica will probably witness a much more marked increase. Already, the frozen southern continent has experienced a three degree rise in the last century. The ice-cap is steadily melting and already, alien plants have invaded, brought in inadvertently by research scientists, mostly on their clothing. The global increase in temperature may usher in an era of global food insecurity, that may contribute to a widespread collapse of social and economic systems. There would be a surge in migration and conflict; people would move away from uninhabitable parts of the world into more desirable areas, inevitably wars over resources will increase. Indeed, you can make a compelling case that many of our modern conflicts are over resources, especially the Middle East, with its vast reserves of oil. Climate change won't end our species completely, but it may devastate us enough to end the modern age and cause a considerable decrease in the population.
More on the Problems Facing Antarctica
- BBC News - Alien invaders threaten Antarctic fringes
The fringes of Antarctica are being invaded by alien plants and tiny animals. An indepth article from the BBC.
Telomeres and Chromosomes
More on Telomeres and the Theory
- Reinhard STINDL - Telomere Erosion in Cancer and Evolution
Reinhard Stindl's own website.
- The final countdown | Education | The Guardian
An article from the Guardian that goes into more detail about extinction and telomeres
The Threat from Within
One of the great mysteries of nature is explaining how species go extinct. 99% of all species that ever lived are now extinct, roughly 4% of them met their end as a result of a mass extinction, this includes the species that have died out in recent times. But what about the other 96%, climate change may play a factor, but can it explain all those billions of extinctions down the ages, its highly doubtful.
Recently, a medical doctor called Reinhard Stindl from the University of Vienna has come up with an intriguing new theory. Before, I explain this theory, let me tell you a little bit about telomeres and their role in our lives. On the end of each of our chromosomes are protective caps called telomeres, these are vital to our well being, without them, the chromosomes become unstable. Each time a cell divides, it never quite copies its telomeres completely. Throughout our lives, the telomeres become shorter and shorter, as the cells continuously multiply. When they become critically short, then age related diseases such as cancer, Alzheimers, heart attacks and strokes increase in likelihood.
The theory then, goes like this; each species has its own evolutionary clock, that ticks through the generations. As each generation passes by, then the telomeres shorten ever so slightly in length, essentially it mirrors the ageing process seen in an individual. Over thousands of generations, the length of telomeres reach a critical length; age related diseases start occurring earlier in life. Eventually, the species experiences a population crash and slides into extinction. This theory has yet to be proven, but it may help explain why previously successful species all of a sudden disappear from the fossil record.
How a Virus Spreads
Is it a Pandemic or Not?
Within the last century, humanity has suffered four major flu pandemics along with HIV and Sars. Living in such a crowded environment increases the inevitability of a major pandemic sweeping the world at least once a century. In 1918, the Influenza outbreak caused the deaths of 20 million people worldwide, not only was that more than all the people that lost their lives in World War I, but it also represented around 5% of the world's population at the time. Today, a similar sort of outbreak would have a devastating impact, if 5% of the world's population were to disappear today then that would equate to 350 million people losing their lives, what a terrifying thought.
However, the chances of a virus wiping out everybody is impossible, as it is not in the virus' best interests to wipe out its host completely. A major pandemic, comparable in scale to Influenza would probably cause a setback that may take years or decades to recover from. In the 13th century, a quarter of the European population was wiped out by the Black Death; recovery was slow, indeed it took more than a century for the population to reach its former level. We can make preparations for a pandemic, but in reality we can never prepare fully, because we can't be certain of what nature will do exactly, it remains to be seen.
What Might Happen, the next time a Pandemic Strikes
An Awesome Book and DVD
A classic Sci-Fi novel from George R. Stewert that tells of a man that survives a pandemic and builds a new community.
Today, in the modern world we are more vulnerable to terrorism because it's very easy for a group with sinister intentions to acquire the necessary materials, technology and expertise to make deadly weapons. The most likely cause of an act of terrorism that would result in exceedingly high casualties could probably come from some sort of chemical or biological weapon. If ever a virus such as Anthrax or Smallpox ever got into the wrong hands, then the consequences would be dire. Modern communications and travel would soon turn a local threat into a multi-national threat at least. In our society, there are many values that we treasure, particularly freedom of movement. As a result there is no definite guarantee that an attack could be prevented. However, the threat of extinction at the hands of terrorism is also impossible, unless some mad scientist decided to blow up the Earth or the Sun.
From the end of World War II right up until the late eighties, the threat of a global nuclear war was very real. In theory, if such a thing were ever to occur then human civilisation could be obliterated, but again the likelihood of total extinction is impossible. In the 21st century, the threat of global nuclear war has more or less vanished, thanks largely to International laws that serve to restrain the use of nuclear weapons. Although it has to be recognised that there are still several potential flashpoints in certain areas of the world, namely the Middle East, India-Pakistan and North Korea. Of all of these, North Korea and Iran are the most worrying, as both are extremely militaristic and volatile. Hopefully the presence of American forces in the Middle East and South Korea should be enough to deter any acts of aggression.
When thinking on terms of geologic time, the chances of us dying as a result of a meteor impact is about the same as dying in a plane crash. In order to cause serious damage to human civilisation, the meteor would have to be at least a mile wide. An impact on that sort of scale occurs every million years or so. If we were to be struck by a meteor a mile wide or larger; millions of tons of dust would be thrown up into the atmosphere, blocking out light from the sun for about a week, thus putting enormous pressure on all plant life including the vast fields of crops that we depend on for food. Chunks of rocks ejected into space by the initial impact would soon be sucked back down to Terra Firma by Earth's gravity and cause huge global firestorms upon impact, another by-product of a meteor impact would be severe acid rainfall across the world.
If Earth were ever hit by a meteor the size of the one that swept the dinosaurs away, then that could very well wipe us out too; but anything smaller would of course cause huge destruction, but its effects would be short term, and given our incredible adaptability we'd probably pull through.
Two Awesome Films
Hans Moravec's Web Page
- Robotics Institute: Hans Moravec
The Robotics Institute at Carnegie Mellon University was established in 1979 to conduct basic and applied research in robotics technologies relevant to industrial and societal tasks.
A.I. and Robots
This particular factor got me thinking of things like the Matrix, Terminator and I Robot. Personally I find the idea of sentient robots disturbing and wrong. But according to Hans Movorec, a research professor at the Carnegie Mellon University Robotics Institute at Pittsburgh; robot controllers double in complexity every couple of years. At this moment in time they are approximately of the same complexity as a fish, but in another fifty years they will have achieved a level of sophistication more or less equal to us. He predicts that by 2050, robots will be able utilise abstract intelligence, be able to learn from us and share our goals and cultural values. He foresees a future already envisaged by Asimov of robots looking after us in our own home, attending to our every need, even going so far to diagnose illnesses and recommend treatment. He also thinks that robots will offer us our best shot of immortality by allowing us to upload our personalities into advanced humanoid robots.
Such thoughts fill me with total dread and fear. I think I'd take extinction rather than having a robot sharing my home with me. To me, this feels like once again man playing God and trying to work outside of nature rather than within it. I wonder what Ian Malcolm from Jurassic Park would have to say about this issue, I'd love to hear his thoughts.
A Ticking Timebomb
How Close We Came to Extinction
- Toba catastrophe theory - Wikipedia, the free encyclopedia
Article from wikipedia,outlining the Toba eruption that reduced the human population to as low as 1000.
Every 50,000 years or so Earth experiences a super-volcano eruption. When it happens, more than 1000 square miles of land is instantly obliterated by ash and lava flows, outside of this 1000 mile radius, the rest of the land is coated in ash, and the atmosphere gets a big injection of sulphur gases, creating a veil of sulphuric acid around the world, that blocks sunlight for years. The result is that daylight turns into a moonlit night.
The amount of damage to the Earth depends on where it occurs and how long the gas stays in the atmosphere. The most recent eruption was Taupo, New Zealand around 26,000 years ago. The most devastating one ever experienced by humans was the Toba eruption on the island of Sumatra around 74,000 years ago. Due to its proximity to the equator, the sulphur gas was injected into both hemispheres. Global temperatures plummeted, causing freezing conditions to spread as far south as the tropics, it lasted for six years, but it was enough to nearly cause the extinction of humanity, in fact evidence indicates that we may have been reduced to less than 10,000 individuals, perhaps even as low as 1000.
A super-volcano is about 12 times more likely to occur than a meteor impact, with 0.15% probability of one erupting in our lifetime. The places to watch are the volcanoes that have erupted before, such as Toba and Yellowstone (last eruption- 650,000 years ago). But more frighteningly, a super-volcano could burst from somewhere new, such as the Amazonian rainforest.