Modeling cells as computer programs

PS Meyers has blog post criticizing a creationist describing organisms as computer programs, and then arguing from incredulity against naturalistic explanations for human development. That’s well and good, the creationist is an idiot, but then Meyers takes it a step further and expresses a dislike of software-type descriptions of development:

The genome is not code, efficient or otherwise. Sure, you can tally up the bits needed to store the sequence in a database, but that is not the same as saying you’ve got the complete information for an organism, or that you have captured the “code” that can be executed to build it.

I’m happy to think of the genome as a program. At the high estimate, 100 million bits (25000 genes * 1000 bps per gene * 1000 bps of regulatory seq per gene * 2 bits per bp) or 12Mb to describe the human genome.

So a fairly small amount of code is enough to generate a person. The small number is clearly enough–it is what humans develop with. The program isn’t written in a bloated computer language. It’s more like hand-tuned (or genetic algorithm-tuned, ha) assembly code, full of GOTO statements and with enough cross connected subroutines to make the block diagram look knotted as a ball of thread.

The size doesn’t seem small in relation to the code. Look at the Mandelbrot Set, 7 bytes to write it down and an incredibly complex result. So clearly a small program can produce a complex result.

PZ considers epigenesis important and a reason to reject the computer program hypothesis as insufficient. Epigenesis is clearly important but I don’t see it as a reason to reject the computer program analogy. The epigenetic information is an expression of the genomic program.

Also, calling the genome a library of components seems too static to me. “Library of subroutines” or “library of services” captures the sense of what is going on better, with different subsets of routines active at any time.

It is interesting to compare computer programs with living organisms, but as this creationist shows it is easy to be mislead (or to mislead) by the analogy. I think any complete description of cellular activity and development will use the concepts used to describe computer programs.

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