Tuesday, January 24, 2012

Using the Origin of Software as a Model for the Origin of Life

I just finished reading Genesis – The Scientific Quest for Life’s Origin (2005) by Robert Hazen, which provides an excellent overview of the current research efforts investigating the origin of life on Earth. Robert Hazen is a former high pressure mineralogist who transitioned into research on the origin of life and astrobiology several decades ago, and is now conducting research in those areas at the Geophysical Laboratory of the Carnegie Institution. As with most researchers working on the origin of life, Robert Hazen views life as a form of self-replicating chemical information, and in Genesis – The Scientific Quest for Life’s Origin he describes the ongoing research into some of the possible steps leading to early life. The book emphasizes the emergence of self-assembling chemical pathways and structures (see The Origin of Software the Origin of Life for details) and the importance of the interactions between organic molecules and mineral structures and surfaces (see Programming Clay) as precursors to the emergence of early protocells using RNA-like organic molecules for genetic material and biochemical pathways for metabolism. Given his geological background, Robert Hazen tends to support the idea that life originated near hydrothermal vents or possibly several thousand feet below the Earth’s surface in porous reservoirs near hydrothermal vents. The pore spaces in the heavily fractured rock near a hydrothermal vent would provide the ideal habitat, with an abundant supply of hot, energy-rich, organic molecules and crystal precipitating ions in the pore fluids circulating through the rock. This environment was also isolated from the planet-wide sterilizing impacts from the late heavy bombardment that peppered the Earth and Moon 4.1 – 3.8 billion years ago with countless impacts from comets careening in from the outer Solar System.

As a former exploration geophysicist this is also my favorite hypothesis for the origin of life. When I was exploring for oil in one of Shell’s offshore concessions off the coast of Cameroon in 1975, we noticed that the oil that was shallow, at a depth of only a few thousand feet, was much heavier than the much deeper oil many thousands of feet below it. By heavier, I mean that it was composed of hydrocarbons with long chains of carbon atoms, which gave the oil a higher density and also made it more viscous. Heavy oil has less value than lighter oil because it has to be cracked down to hydrocarbons with chains in the gasoline range of seven to eleven carbon atoms. Lighter oil already has lots of hydrocarbons with chains in the seven to eleven carbon range, so all you have to do is boil them off in a distillation tower to make gasoline. At first Shell was perplexed by the differences in densities between the shallow and deep oil since the shale source rock for both of them was the same formation many thousands of feet below both the shallow and deep oil sandstone reservoirs. Shell’s working hypothesis was that bacteria in the more shallow sandstone reservoirs were eating the lighter fractions of the crude oil in the reservoirs, leaving behind the longer chain hydrocarbons, and that was why the shallow oil was heavier than the deep oil. The deep oil was far too hot for microbes to live in, so these sterilized deep reservoirs managed to keep their lighter fractions in place for millions of years because they had no pesky microbes feasting upon them. So there still are plenty of microbes living way down there in the Earth’s crust, and we may all be their very distant descendents.

Genesis – The Scientific Quest for Life’s Origin describes the difficulties of trying to piece together the emergent steps leading to life in the deep past because nobody was around to record the details, and instead, we have to rely upon whatever vestiges of the steps remain. All this gave me an idea. As I explained in Self-Replicating Information, there currently are three forms of self-replicating information on Earth – genes, memes and software, with software rapidly becoming the dominant form of self-replicating information on the planet. And since software is evolving about 60 million times faster than life on Earth, the origin and evolution of software on Earth over the past 2.2 billion seconds, ever since Konrad Zuse cranked up his Z3 computer in May of 1941, provides an excellent model for the origin and evolution of all forms of self-replicating information because all of the historical data is still largely at hand and most of it occurred within living memory. In fact, software is the only form of self-replicating information on the planet that does have a well documented history to examine. One could also try to explore the origin of memes, but like the origin of life, the origin of memes occurred a very long time ago, and since memes require the emergence of conscious intelligence in order to self-replicate, something we know very little about, studying the origin of memes is very problematic.

In A Proposal For All Practicing Paleontologists, I outlined a cross-functional research program for the investigation of the evolution of software, which proposed that researchers from the departments of paleontology and computer science of a university team up with the IT department of a local major corporation in order to help shed some light on some of the more difficult aspects of the evolutionary history of life on Earth. For example, in An IT Perspective of the Cambrian Explosion, I tried to show how comparing the evolutionary history of software to the evolutionary history of living things in deep time could help to explain the Cambrian Explosion. I think a similar research program would be very helpful in investigating the origin of life on Earth. Again such a research program would require researchers at a university working on the origin of life to team up with the computer science department of their university and then approach the IT department of a major corporation. In How Software Evolves, we saw that there indeed is a very close relationship between the evolution of software in an IT department and the evolution of living things, so once this cross-functional team became comfortable with working with each other and with being able to relate the evolution of living things to the evolution of software running on a large corporate network, they could then begin to work backwards in time to the very early origins of software, to help inspire some additional unconventional ideas about the origin of life, or to firm up some of the more conventional explanations already in existence.

For example, in The Eerie Silence: Renewing our search for alien intelligence (2010) Paul Davies proposed that life may have originated many times on Earth, using chemical technologies different than what standard life uses today, and perhaps their descendents are still amongst us as a shadow biosphere hiding along side of standard life. Paul Davies is currently putting together some research strategies for finding these “alien” forms of life that might be right in our midst. Paul Davies contends that because these ancient forms of alien life use dramatically different chemical technologies, they would go unnoticed by our standard lab technologies that are geared towards dealing with standard life forms. Similarly, in Crocheting Software, I showed how crochet and knitting patterns were a shadow form of software with a much earlier origin than computer software, and that they also evolve over time in a similar manner to both computer software and living things. In support of Paul Davies’ contention, most IT professionals also probably have a hard time of thinking of crochet and knitting patterns as alternate forms of software because they are so dramatically different than the standard computer software that they deal with on a daily basis.

Another important factor in the early origin of computer software was the parasitic/symbiotic relationships that it forged with the technological meme-complexes of the 1940s and 1950s. In Self-Replicating Information I explained how most forms of self-replicating information begin as a parasitic mutation of an already existing form of self-replicating information.

Self-Replicating Information – Information that persists through time by making copies of itself or by enlisting the support of other things to ensure that copies of itself are made.

The Characteristics of Self-Replicating Information
All forms of self-replicating information have some common characteristics.

1. All self-replicating information evolves over time through the Darwinian processes of innovation and natural selection, which endows self-replicating information with one telling characteristic – the ability to survive in a Universe dominated by the second law of thermodynamics and nonlinearity.

2. All self-replicating information begins spontaneously as a parasitic mutation that obtains energy, information and sometimes matter from a host.

3. With time, the parasitic self-replicating information takes on a symbiotic relationship with its host.

4. Eventually, the self-replicating information becomes one with its host through the symbiotic integration of the host and the self-replicating information.

5. Ultimately, the self-replicating information replaces its host as the dominant form of self-replicating information.

6. Most hosts are also forms of self-replicating information.

7. All self-replicating information has to be a little bit nasty in order to survive.

In Programming Clay, I highlighted Alexander Graham Cairns-Smith’s theory, first proposed in 1966, that there was a clay microcrystal precursor form of self-replicating information to both RNA-like organic molecules or self-replicating metabolic pathways. Finally in SoftwareChemistry and SoftwareBiology I showed the very close similarities between the softwarechemistry of computer source code and the biochemistry of living things. With so many close similarities between computer software and living things, it seems to me that it naturally makes sense to look to the origin of software as a model for the origin of life. After all, what else do we have that even comes close?

Comments are welcome at scj333@sbcglobal.net

To see all posts on softwarephysics in reverse order go to:

Steve Johnston

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