Self and the Beginning of Life 59“9x6” b2726 Self and the Phenomenon of Life: A Biologist Examines Life from Molecules to Humanitytell. The analogy is rather like a forest fire. It takes time to build up the
right physical condition in favor of combustion, but once a spark starts
the fire spreads rapidly.
Life is built on chemistry but it ends up being more than chemistry.
When molecules group together under certain propitious conditions,
they interact, interconnect and form complex, dynamic, hierarchical net-
works. It is then, and only then, that an assemblage of matter expresses a
unified goal, or what appears to be a goal, to continue its own existence,
including making more of itself. It is as if life, once born on our planet,
announced itself with a determination to go on forever.
3.22 The Birth of Life is the Birth of Self
The Earth was formed 4.5 billion years ago, and the evidence of life
dates back to about 3.5 billion years. The Earth in the first half billion
years is considered to be too tumultuous to permit any living things to
occur, so it is reasonable to assume that the process leading to the begin-
ning of life started around 4 billion years ago. The question is, was the
formation of life a gradual and protracted process, taking place over sev-
eral hundred million years, or a relatively rapid one, occurring over a few
thousand years? I believe the process that culminated in the appearance
of life is gradual, arduous, chaotic, and error-prone, but the birth of the
first life could have taken place within a watershed period, a relatively
short geological time frame. The slow transition period would allow time
for carbon based molecular chains to form, extend, and accumulate;
some metal-based catalysis to take place; some short, random sequenced
polypeptides and oligonucleotides to form (not using the whole gamut of
modern-day amino acids and nucleobases); and some simple lipid ves-
icles to appear, coalesce, and split. We can call these potpourris of car-
bonaceous materials “pre-life”, “pre-cell”, “proto-life”, or “proto-cell”,
but they were not true life. The first real life could be extremely sim-
ple, much simpler than any we can see today, but nonetheless it should
be complete and capable of independent existence, which should meet