CREATION OF LIFE
AND BIOLOGICAL EVOLUTION ( Page 3) |
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| The Origin of Life. |
| Now comes the million-dollar question: “How did
it all start?” How, when and in what form did life appear on
the earth? It is certain that life must have started in its simplest
form. But how simple is the simplest form of life? Fifty years ago
many scientists believed that they knew all about the cell. But today
they are not so sure. Craig Venter is the head of Celera International,
one of the two firms that decoded human genome, one who studied in
detail the genes present in the human DNA. In 1996 Venter entrusted
a team under Scot Peterson with a 10 year mandate to find answers
to two questions: “How many genes does a cell need to live?
And which genes are they?” After 5 years the team is still working
on the project, on an organism called Mycoplasma Genitalia, without
a clear answer in sight. This particular organism was chosen because
this was the one with the lowest number of genes, 470 only. Compared
to this the bacterium Haemophilus Influenzae has 1700 genes and the
human being has around 30000. Venter himself had hoped to “find
out how a cell works” when he was sequencing the genome of the
bacterium Haemophilus Influenzae, but he found it too complex. This
is what Venter had to say: “I naively thought that we could
have a molecular definition of life, come up with a set of genes that
would minimically define life. Nature just refuses to be so easily
quantified.” In short, we have to conclude that the simplest
form of life is not all that simple. |
| Since 1859, when Darwin Published “On the Origin
of Species”, scientists have been trying to create life from
the basic chemicals in the lab. They have not succeeded so far. In
1950 Stanley Miller subjected a mixture of methane, ammonia and carbon
dioxide to electric sparks and succeeded in getting some amino acids,
simple organic compounds that are the building blocks of protein.
He had assumed that the atmosphere of the ancient earth consisted
of these gases and the electric sparks did the job of lightning. Now
we know that ammonia was not present in the atmosphere of the earth
at any time in its history. Many other theories on the origin of life
on earth by chance combination of molecules had to be given up due
to lack of sufficient evidence to support these theories.50 years
after Miller’s attempt, scientists still have not produced anything
that resembles a protein or the RNA or the DNA. That is why Craig
Venter said in 2001: “Right now the only way to get life is
from life itself.” Here he is referring to the attempts of his
team to assemble the simplest form of DNA that has the self-replicating
property from the genes of simple bacteria like the Mycoplasma Genitalium. |
| “No one knows how life arose on the desolate
young earth, but one thing is certain: life’s origin was a chemical
event,” writes Robert Hazen of Carnegie Institution of Washington,
in a lengthy article on the possible role minerals might have played
in the chemical reactions that led to the formation of the first living
entity. “Scientists are far from creating life in the laboratory,
and it may never be possible to prove exactly what chemical transformations
gave rise to life on earth” he says elsewhere in the same article
(Scientific American April 2001). |
| When you think of it, the infant earth was the least
likely of places to support life, let alone support the creation of
life. In the absence of the ozone layer, the ultraviolet rays would
have destroyed or broken up any simple life forms if present. There
was no oxygen at all in the air. The atmosphere consisted of carbon
dioxide, nitrogen, methane and sulphur. In short, the earth was a
very inhospitable place for life, as we know it now. When Robert Hazen
wrote, “no one knows how life arose…” that “no
one” did not include many of us, not me any way. I know for
certain what most people believe, some strongly, some weakly, that
life arose on our planet by a miracle, by a feat almost improbable
if not impossible, the miracle of “creation” by God. In
other words I know now what everybody before the advent of modern
science knew, that God created life. |
| One might ask: “Cant we give a rational explanation
of the origin of life in terms of chemical reactions instead of bringing
in the idea of God, which idea is very difficult to explain in scientific
terms?” Is it not reasonable to assume that with the energy
of the sun or the lightning or that of the volcanic vents on the ocean
floor, certain compounds would have by chance combined together forming
the first simple, self-replicating molecules? Many are still trying
hard to find experimental evidence to such a hypothesis. But the probability
of the molecules in air or water combining ‘by chance’
to form life is less than the probability of a typhoon passing through
a junkyard making the various pieces of junk to join together by chance
to form a Jumbo Jet ready to take off. Compared to the assembling
of chemicals to form a DNA or RNA molecule or a cell, the work of
assembling a Jumbo Jet is rather easy or at least possible. Man has
done it. But he has failed to make life from lifeless atoms and molecules. |
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