A totally satisfactory answer to "what is life" has not really been discovered. It is often defined in terms of a bio-chemical structure or cell which organises itself to independently reproduce and duplicate itself. The living organism is able to metabolise, proteins and enzymes to generate the power to self-replicate and maintain itself in a state of homeostasis. The living cell uses the information stored in DNA to maintain a blueprint to reproduce and control the bio-chemical processes needed to sustain its own life. The cell maintains itself in a state of homeostasis and draws sustenance from the environment. The cell is also capable of reacting to its environment and is subject to the process of natural selection. The cell can temporarily resist the the second law of thermodynamics and exist in a state of negentropy or negative entropy by actively maintaining organised systems. But, eventually all individual cells succumb to the laws of nature and die.
There is some dispute as to whether viruses, whose genetic material is composed of either DNA or RNA , are alive or not. Viruses cannot independently reproduce outside of a living host cell. It is difficult to define when life becomes life. When does an organism which is slightly more complex than a virus become alive? Is there an actual point where it can be said, "life begins". My own view is that life is a property of the universe. The universe is capable of organising itself along the line of a continuum to create what we recognise as life, but there is no actual point where life starts. The universe, therefore, is in itself alive but in some places, in time a space, it is more organised than others to produce life and even self recognition. This time and place exists on the planet Earth, which is the only place that life, as defined by human beings, is proven to exist.
According to my framework of reference, the evolution of life does not require the existence of a god to drive the process either by a form of creationism or intelligent design. So there is no intervention by a supernatural being. As far as I am concerned there is no evidence to suggest that a supernatural being or god created the universe to start off the whole chain reaction of being. When religious philosophers provide me with testable evidence, I shall rethink my agnostic or atheistic stance.
Venter has not created artificial life or played God for two reasons. The first: life could be an actual property of the universe itself and therefore exists everywhere and anywhere. The second: if life is to be defined as a self-replicating cell, he has not designed a unique genome and he has not created unique cytoplasm to go with it. Technically, he has transferred the genome (DNA) from one form of bacteria , Mycoplasma mycoides, into the cytoplasm of a closely related species, Mycoplasma capricolum, which has been stripped of its own genome (DNA). This new living cell was then tricked, bio-chemically, to start reproducing as if it were a new variety of the Mycoplasm mycoides organism. Technically, this feat has been performed before but this time the transplanted genome was constructed from a genetic blueprint held on a computer database. The four nucleotides used to make the donor genome DNA were assembled using yeast cells programmed with the "blueprint". Life itself uses the medium of DNA to store the blue print of a living cell, however this blueprint could just as well be stored on a computer database or even sheets of paper. The technical genius displayed by Venter was both being able to create viable DNA, from information on a database, and then transpose that DNA to take over the cell functions of a related species. This is very advanced genetic engineering and modification. DNA is now able to replicate itself indirectly via the medium of a computer database.
A means of modifying the design for a living cell has now been created by using a new genetic modification technique. This has the elements of intelligent design. But to create a completely artificial life form, which performs a function or functions predetermined by a human plan or scheme, is an entirely different matter. Natural life has evolved to meet its own purpose to replicate itself and survive. Would a purpose built life form be able to compete against other organisms to evolve into a species that could survive for millenia or longer? Would such a life form be be subject to the theory of natural selection at all? Could a "life form" that was not capable of evolving in its own direction, whilst competing in natural environment, be said to be truly alive?
Man might shortly have the power to create truly artificial life and this raises a number of philosophical issues. Would the newly designed species be a form of creationism as espoused by the religious philosopher William Paley in the 19th century? Paley's beliefs were a forerunner of intelligent design i.e. God created all of life to a design according to his purpose. God created man who creates artificial life ; so this is proof of intelligent design. I do not think so, as there is no tenable evidence for such a theory.
It has been suggested that one of the biological benefits of creating artificial life would be to solve the problem of fuel production without having to mine for fossil fuels. Vast industrialised scale cultures of artificial algae could be used to extract carbon dioxide from the atmosphere to produce methane or petroleum as clean fuel. We could even use such artificial life to reduce the concentrations of carbon dioxide in the atmosphere. But let us think for a minute. What if we become dependent upon such artificial life? What happens if our economies become dependent upon fuel produced by industrialised vats of algae? How would natural plants be able to compete for the carbon dioxide in the air? What happens if we upset the balance of the atmosphere to remove too much carbon dioxide? Other natural plants may not survive and our world could be plunged into an unexpected ice age, because global warming might have been dangerously and uncontrollably reversed.
What would happen if a natural virus found a way of infecting and killing the vats of artificial algae? We might be cut off from our fuel supplies before a solution is found. The genetic engineering implications should be carefully thought out before artificial life is deployed to perform an industrial function.
One of my greatest fears is the potential to create an artificial bacterium which is capable of wiping out human beings in the form of a weapon. Human beings might not have any resistance to a new and potent form of artificial disease. We could find that a designer biological weapon could kill everyone on the planet.
We should also be careful that an artificial life form does not damage the ecosystem if it accidentally escapes into the natural environment. Nasa was very careful to decontaminate the Apollo space ships returning from the moon and to hold the astronauts in quarantine. This was for very good reason; they did not want to take the risk of alien life infecting the Earth. We should be equally as watchful with artificial life.
I am totally in favour of using genetic engineering to further scientific knowledge. I am also in favour of considering the ethical and philosophical implications of using this science. When it comes to biological engineering on an industrial scale then I am both sceptical and very wary "intelligent design" could easily become "dumb design". The dangers are there for all to see: let us not fall into an hubristic trap of our own making.
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