Sunday, 31 January 2010

The Infinite Loop : An Evolutionary Noose

There are very many of these infinite loops in the biological world - and they cannot be closed or broken into apart from divine creation or intervention.

Here is one of the biggest.

The Cyanobacteria

The cyanobacteria are one of the earliest forms of life known, if not the earliest. They date back to 3.5 BILLION YEARS ago. So they say, anyway.

The cyanobacteria perform 2 functions which are absolutely mind-blowing, when you consider that they are probably the earliest form of life on the planet. They are found in huge bundles called stromatolites in many places on the earth's surface.

They carry out photosynthesis - which means that they possess that most complex system of biochemicals which includes chlorophyll.

Even more staggering, they fix atmospheric nitrogen directly. They convert the totally inert gas directly into biological compounds which other living things can use after the c-b's have died.

Now here's the noose, sorry, loop.

DNA is made up of molecules called nucleotides. Nucleotides can't be made without fixed nitrogen, because nitrogen gas simply does not combine with anything - especially not at temperatures at which life can survive.

Also, amino-acids, that essential component of proteins, cannot be made without fixed nitrogen.

So proteins cannot be made without amino-acids, which cannot be made without fixed nitrogen, which cannot be made without cyanobacteria.

The cyanobacteria cannot reproduce or make proteins without DNA, and both proteins and DNA REQUIRE fixed nitrogen.

So the circle closes permanently.

Without cyanobacteria - no fixed nitrogen is available.

Without fixed nitrogen, no DNA, no amino-acids, no protein can be synthesised.

Without DNA, no amino-acids,protein, or cyanobacteria are possible.

There are several other points here, in addition.

These bacteria also photosynthesise (a process requiring a large number of proteins, both in the execution of the reactions, and in the structure of the membranes of the chloroplasts). Let's say 30 for argument's sake.

They fix nitrogen - and so require that marvellous enzyme nitrogenase, which is really a combination of 2 separate enzymes, proteins to be precise.

None of these, as shown above, can be made without fixed nitrogen.

Nitrogen cannot be fixed without them. So which came first, the chicken or the egg?

But wait, cyanobacteria are facultative anaerobes - meaning that they can respire either aerobically or anaerobically.

The complexity of two respiratory cycles is very high: the Krebs cycle alone requiring about 12 enzymes, and the anaerobic requiring somewhat fewer, say 8.

So in order for the cyanobacteria to survive, about 40 enzymes are already involved - none of which can be made without fixed nitrogen. But the c-b's are doing the fixing! So the noose tightens.

Abiogenesis research is time-wasting. There is no way to break into this loop, which is a prime requirement if life originated from non-life.

Of course, it couldn't, and didn't.

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