Start | Introduction | Part One: Islands | Part Two: Do or Die | Part Three: Send in the Clones
Part One: Islands
People have always explored, gone beyond their boundaries. Human nature propels us past the next ridge or across the ocean or to the tops of mountains. But today we have no hills left to climb, no oceans left to cross, no readily visible horizons to beckon us forward, no challenges left here on earth--save survival--to inspire the hearts and minds of humankind.
During our geologically brief tenure as custodian and caretaker of the planet (a job we have taken much too lightly, I fear), we have exploited and utilized everything we have come across, and this has allowed us to expand and constantly advance. When a group of prehistoric humans ran out of food or water in a particular area, they just walked on past the next ridge and began utilizing the resources they found there. When we came to an ocean or sea, we built boats and continued on our quest for resources and habitable terrain. Unfortunately, some species do not have this luxury--perhaps not even us anymore. A brief discussion of ecosystems, particularly closed ecosystems, is in order.
An ecosystem is an integrated group of interacting biological organisms located in a particular habitat, and the physical environment in which they live. There are two major types of ecosystems: open and closed. A continent is a relatively open ecosystem. If conditions such as climate, types and numbers of predators, or food supply change for the worse, a species will simply migrate and find a new habitat that is more to their liking. Continental species are spread far and wide and thus survive almost any assault on their existence.
An island, on the other hand, is a closed ecosystem. Island species rarely have the means to leave their limited habitat. They are often quite limited in numbers because of their small geographic range, making them much more vulnerable than their continental counterparts. For them, an upset in the balance of nature can be catastrophic. A closed ecosystem, such as an island, often leads to extinction of species--by disease, natural disaster, normal population fluctuations, or introduction of a predator.
Island biogeography is the study of island habitats and the distribution and dynamics of the species that live there. Well over half of the 724 known animal extinctions in the last 400 years were island species. Yet continental habitats far outweigh island habitats. The unique dynamics of island biology and ecology drive this disproportionate number of extinctions.
While many animals have become victims of a closed ecosystem (such as the black lemur, the komodo dragon and the kakapo, all of which are close to extinction), perhaps the most famous are the dodo bird and the moa, because they became extinct.
The dodo bird lived on the island of Mauritius in the Indian Ocean and nowhere else. It lived there undisturbed for so long that it eventually lost its need and ability to fly. The dodo had no real enemies on Mauritius until 1505 when Portuguese sailors first landed and began using the 50 pound dodos for fresh meat, a welcome addition to their usual rations. Rats escaped from many of the ships and made short order of the dodos eggs, laid in nests built on the ground. The last dodo was killed in 1681, its species a victim of the combination of human exploitation, introduced species, and the unique dynamic of island ecosystems.
The moa, a 200-kilogram flightless bird that sometimes reached heights of 3 meters, inhabited the islands of New Zealand until about 500 to 700 years ago. Until the arrival of the Polynesians on the islands about 1000 years ago, the moas had few enemies. The Polynesians hunted the bird for food. The moas, living on an island, had nowhere to run when the new predator, humans, arrived. Within a few hundred years the moa became extinct. Had either the dodo or the moa lived in an open ecosystem like a continent, they might still be alive today.
But not all island species become extinct. Some organisms that developed on islands eventually evolved the potential to leave that island, either under their own power, or by using the power of the wind or ocean currents. Birds evolved wings and flew to the next island (island hopping). Other animals escaped on floating islands of organic debris that sometimes break off from islands. Some plants evolved seeds that were light enough and aerodynamic enough to take to the wind in their quest for expansion and survival. Certain varieties of coconut trees spread by dropping their coconuts in the ocean and using the ocean currents to take them to other islands or continents. These and other species spread and flourished in their newfound surroundings.
A bottle of wine is another example--perhaps the ultimate example--of a closed ecosystem. When corked, the bottle contains live yeast (the top-of-the-food-chain organism--the only organism), fruit juice (the biome or habitat in which they live), and sugar (their only source of food). The yeast eat the sugar and, having a seemingly choice environment, multiply. Unfortunately for them, the yeast excrete alcohol as their waste product. The alcohol builds up and eventually poisons the yeast, killing them (or at least most of them). The resulting Cotes du Rhone, Chateau Neuf du Pape, 47 may be tasty, but it is the unfortunate result of a species outgrowing its ecosystem and poisoning itself to death in its own waste. What the yeast dont know is that they live in a closed ecosystem. They need to pop the cork and find new horizons to explore and new resources to utilize.
The general rule here seems clear. Species that find a way to break the barriers of their closed ecosystem survive. Species that dont cease to exist. While the loss of a few (or not so few, as the case may be) species is not of grave concern to the survival of the human species, this process of extinction of species in closed ecosystems may have catastrophic implications for humankind itself.
For a small tribe in humankinds history or prehistory, earth must have seemed like an open ecosystem. Another valley or hill beckoned them to move on, as did the last one, to spread their seed, to populate the earth, to explore the unknown domains of a seemingly endless earth. To our present global society, however, earth itself is a closed ecosystem, an island in space, a bottle of wine with a cork made of our own short-sightedness.
And our island is becoming increasingly difficult and dangerous to live on. As the human population increases, the amount of arable land decreases. This will eventually lead to mass starvation. We use oil and petroleum products as if they will last forever, but we know they will not. We log vast stretches of forests and rain-forests, destroying the mechanism that supplies us with oxygen. We dump millions of tons of waste into our rivers, oceans, and atmosphere each year, poisoning our own closed ecosystem to the point where it will no longer support us. The earth will soon become unlivable.
But even if we found a way to feed the growing population, save the oxygen-producing forests, and reverse the damage caused by our waste products, our fate would still be sealed. The sun creates its enormous, miraculous, life sustaining nuclear energy by burning hydrogen, turning it into helium and other elements. In another four or five billion years our sun will deplete its supply of hydrogen, expand into a giant red star engulfing Earth, and eventually cool and contract to a dark black cinder. If we do not leave Mother Earth and indeed our solar system by then, we will die--and so will every other life form on earth. Complex, beautiful Life, Life that took the universe 15 billion years to produce--perhaps the only Life in the universe--will be lost forever. Like it or not, weve been served our eviction notice.
Flowers drop their seeds to the wind to spread them near and far. On the island of earth, humankind is the silver seed, the one species on earth that has advanced far enough technologically to break through the bonds of our atmosphere and earths gravity and spread our seeds, as well as the seeds of every other species, to the far reaches of the galaxy, and thus insure our survival. We have or soon will have the means, but do we have the courage and the foresight? As the only species we know of capable of bringing Life to the galaxy, we have the undeniable duty to do so. We need to pop the cork of the wine bottle, and open up the vastness of space--the solar system, the galaxy, and eventually the universe--not just to human visitation, but to human settlement and utilization, before we ourselves become extinct, suffocating in our own excrement (pollution) like yeast in a wine bottle. We also need to take with us the lessons we have hopefully learned from the destruction of our present home.
What humans long for and need is the freedom to expand. We have no real freedom here on earth anymore. Space will give us that freedom, not just for a generation or two, but for all time. We need to break the confines of earths gravity and the prison walls of earths atmosphere and seek the open spaces, as did our ancestors when they colonized the continents or homesteaded the West. We need to use our technology to turn the closed ecosystem of earth into an open one. The only truly closed system, as far as humans are concerned, is the universe--by definition. And there lies our true date with destiny. Only there, in the vast reaches of the universe, can we humans survive long enough to find the true limits of our imagination and potential, if indeed there are any.
But our problem is more than a global societal problem, for human beings, too, are islands. Each of us must break the bonds and constraints that we place upon our own minds; no one can do this for us. We must break free of the self-imposed limits on our imagination and accomplishments. We can only conquer outer space by first conquering inner space--the space between our ears. We must, each of us, believe that we can conquer space because we can no longer afford to leave the colonization of space to future generations.
We must all make the decision and commitment, individually, as a nation, as a world, to support any efforts to colonize space, either public or private. We must convince our leaders and the public of the necessity of space colonization. We can do this. We must. As former president John F. Kennedy might have said were he still alive, we choose to colonize space, not because it is easy, but because it is absolutely necessary to our survival.
Well I dreamed I saw the silver spaceships flying in the yellow
haze of the sun
From the song After the Gold Rush by Neil Young.
Start | Introduction | Part One: Islands | Part Two: Do or Die | Part Three: Send in the Clones
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