Thursday, January 11, 2007

Some Thoughts on Information

Some thoughts on the compartmentalization and dispersion of information in the biological world in response to questions posed by The Growlery.

This is such an interesting topic, and it ultimately reflects on the larger question of human knowledge, that it is certainly worth pursuing. Let me say from the outset that I am in no way an expert on these matters. I prefer to be viewed as a curious layman. And, I am sure, that people like Daniel Dennett have explored these issues far more deeply than I could even imagine (I have two of Dennett’s books and another on consciousness that I have yet to read). However, to just paraphrase what another writes, no matter how elevated, isn’t half as fun as thinking about it yourself. That’s why I like the Internet, it allows this kind of thing for a while (until the Korporate Takeover).

When was the first information necessary for an organism to survive? Well, it must have been pretty early in evolution that informational molecules were required. If we look on DNA as the current and ultimate repository of biological information, some prototype informational molecule must have been present from the word "go" to direct reproduction. If we had time travel, this is the first thing I would find out. What was the ur-molecule of life? Some have speculated that it was RNA, or an RNA precursor, but I think that unlikely. Even RNA, with its backbone of sugars, is much too complex. In any case, the necessity of information for survival dates from the beginning.

It goes without saying that this is what separates the animate from inanimate. There is no example that I know of where the inanimate is driven by information from another source. The crystallization of minerals into their complexity simply follows the second law of thermodynamics with the atoms settling into their respective potential wells in energy space. (This does mimic the organization of kinetic space in cellular metabolism but that is directed by DNA. More on this later.) In any case, the inanimate does not evolve.

Of course DNA and RNA are now the basis of all life, including pseudo life such as viruses. One has to wonder at how and why these molecules came to hold the position they do. In addition to being a very slick means of both reproducing and directing cellular events, the latter by taking information stored in the genetic code to direct the formation of proteins, these molecules are also easy to mutate. Without mutation, there would be no evolution. But mutation changes the information. Most mutations destroy information in that they direct the synthesis of dysfunctional or afunctional proteins. But some mutations, the saints among men, are actually “superior” or “new” proteins (and the use of the words “superior” and “new” here is very loose). They contain new information! (and “new” here is very tight). That is, the configuration of DNA base pairs is different, and this is new information. Of course, there is nothing new under the sun and some information has had to be “destroyed.” This raises the question if information can ever be destroyed. Once information has been present, even if the physical repository (here DNA) is it possible to destroy it forever? If the DNA for unicorns was once present (just like the DNA for DoDo birds and 99% of the other species that have ever existed including dinosaurs) does that mean that it never disappears, even if the information is not in real space? A mathematician must answer this question.

One should not dismiss lowly organisms such as bacteria from having sophisticated information handling (and needs). In addition to bacterial DNA (several have had their total sequence determined) there is bacterial phages, or viruses (virii?) that infect bacteria. In addition to being useful in the new science of gene therapy (getting DNA into human cells) they also carry information between bacteria in the process of infecting and destroying the bacteria (its every bug for themselves in the nether world.) This can be particularly nasty for humans because when a bacteria mutates its DNA to become resistant to an antibiotic, that new information can be relayed to all the other bacteria in the world in very short order by the intervention of bacteriophages. In this way, staphylococcus aureus has become resistant to almost all conventional antibiotics causing serious amounts of trouble treating infections with this common bug (the scourge of MRSA, of methicillin staph aureus).

Even inside the bacteria the information becomes more or less localized. However, it is not until prokaryotes evolve to eukaryotes, and we have a nucleus in the cell that we have true localization. At that point, we need messenger molecules to take the information out of the nucleus (messenger RNA) to the site of protein synthesis (ribosomes). Almost like a cellular internet.

In any case, while one is tempted to relegate “information” to higher organisms and even restrict it to humans, the reality is that all of life is based on information. However, as the Growlery points out, there is a hierarchy of information placement, though he restricts it to the human world:
… a tribal system of oral history and a Googlised internet are both points on the same continuum, albeit separated by an arc of accelerating complexity curve.
As organisms get more complex, information, information storage, and information access becomes more complex. At some point, information begins to be stored outside the organism. Now, to be sure, one can never separate an organism completely from its environment, everybody needs a Petri dish. We would have no viruses to taunt us if there had never been bacteria to harbor their growth. But we wouldn’t be able to eat steak either, since the intestinal flora help in digestion, including absorbing vitamins. What we mean here is that organisms extract information from the environment in order to exist, but I am not exactly sure how to say this. Is there a difference between my Googling “phage” on the Internet and a bacteria sucking up the phage du jour? This needs a lot more thought. What exactly do I mean by “extracting information from the environment” and how does this differ from just receiving sensory input. I know what I mean but I can’t express it. There is a difference.

Fast forward to mammals who walk upright. I have not read “The Singing Neanderthals: The Origins of Music, Language, Mind and Body” by William McNeill yet. I did read the NYRB review. It is an intriguing set of hypotheses but, ultimately, an exercise in metahistory. We cannot know what really went on in the camps of Neanderthals. However, it is a good bet that they did develop verbal communication. Most important here is that communicating by sound may have resulted in the establishment of a repository of information that, while not physically outside the individual, may be described as cultural or collective knowledge. Now, immediately you will put forward the objection that this is no different than the “instinctive” knowledge of bees in a hive or ants in a hill. Certainly those insects function with a certain amount of community information, and, they communicate. Ants with their pheromones and touch, bees with their visual dance.

But, somehow, once the Neanderthal started to collect information as language, I think we entered into a new era. You might disagree with me here. What we do know is that there were many thousands of years of oral tradition between the “Swinger” singers and the oral tradition of Homer. On the scale of true evolution, of course, it was miniscule (see the time line of evolution that was circulating on the Web in the last few years to counter the Biblical time frame.)

It is amazing, though, that Homer and the Neanderthals were both at the same level in terms of information. Of course aesthetically (a rather subjective thing) they are miles apart. It is interesting that the aesthetic appeal is due to complexity since there is no difference, basically in the level of information between apes singing around a fire and Greeks singing around a fire. This, of course, raises the question as to how complex the information can get? What is the upper limit? Is there always an upper limit and have humans reached the upper limit for our current brain?

So, next to take up information after Homer. It seems like the surface hasn’t even been scratched.

2 comments:

Felix said...

Wonderful - what an exhilerating read, first thing in the morning - thank you!

Comments have to be small and focussed, so I'll take only one fragment:

DrC> It is amazing, though, that
DrC> Homer and the Neanderthals
DrC> were both at the same level
DrC> in terms of information. Of
DrC> course aesthetically (a
DrC> rathersubjective thing)
DrC> they are miles apart

They were also miles apart in another sense: the geosocial reach of their information sharing.

The neanderthals, I hypothesise (as you say, I cannot know for sure), were storing information as language within a social unit which was self contained: each individual saw the other members of the storage unit (the tribe) on a daily basis. The storage of informtion extended eyond the life of the individual temporally but not spatially.

Homer, on the other hand, was the transmission vector for information which spanned an area many hundreds of kilometres acoss, encompassing multiple groups of individuals which would never physically meet.

More than that: it was a vector which crossed not only time and space but linguistic barriers as well, surviving code translation into the adjoining nonGreek langage communities.

MR said...

fantastic, fantastic post--thank you...I put up the Iraq cost counter on my website, too--wonderful idea! (I hope you don't mind!)
MR