Download Suggested theories on the origin of life— A summary of the Trottier

Suggested theories on the origin of life— A summary of the Trottier
Symposium 2007
The beginning of life on Earth is largely unknown. We can estimate the time
the planet was originated and conclude that life came into existence very quickly,
but since there are no fossil samples of the most primitive form of life or the
conditions under which it first developed are unknown, we cannot accurately trace
the ‘spark’ that brought it about.
Some records suggest that the first form of life under the primitive
atmosphere was bacteria inhabiting in a wide range of organic material.
Several scientific experiments have tried to simulate the archaic conditions in
which life originated; particularly important is the Miller-Urey experiment which
formed amino acids which generate proteins in living cells, as well as some of the
building blocks for nucleic acids.
It is commonly accepted that from the very beginning there was some genetic
material which led to the creation of life. But scientists disagree on the first organic
source which contained a genetic code. Some argue that it was DNA structures,
others state that proteins where the first code carriers. This debate went on for
decades without finding which of these came first. As P. Antonio Lazcano from
UNAM University showed, RNA is now considered by many to be the first
molecule able to store genetic information and catalyze chemical reactions.
P. Robert Shapiro (NYU) mentioned two of the main creation theories:
creationism and the rise of life from non-living matter.
Two main things are included in this second premise: that life is the result of
an improbable event and therefore Earth might be the only living planet; or that it is
the mere result of cosmic evolution.
P. Shapiro believes that life was originated by an unlikely accident, a series
of improbabilities driven by a source of energy, given the fact that something as
complicated as DNA could not have formed by itself.
The question of how the first organic molecules came to Earth still remains.
They are thought to have been originated by a Supernova 7000 light years away.
According to Dr. Steven Banner life must be: the product of water, these
organic molecules, and Darwinian evolution. Otherwise, if these molecules had been
left alone the creation of life would have been impossible.
The RNA is thought to be the ribose-phosphate backbone, but because of its
instability there has to be an alternative, probably boron, which stabilizes ribose.
Contrary to the belief that life originated from a simple RNA structure, P.
Stuart Kauffman believes that life on Earth originated from complex reproducing
molecular systems which led to the inevitable creation of life.
Even though there exist different theories, the search for the origin of life
anywhere in the universe is constrained by our terrestrial understanding of biology
and natural sciences, therefore new theoretical models must be observed to
strengthen the possibility of ever finding the origin of life.
Rodrigo Espinosa
Suggested theories
on the origin of life
A summary of the Trottier Symposium 2007
Rodrigo Espinosa
February 12th, 2010
ID: 260368325