Thursday, July 18, 2013

The Mother of All N-Factorial Problems

An objection is made about my saying:

The universe of events and phenomena that are proposed to comprise natural selection are no less than every aspect of every life in the billions of years of the history of life on earth in excruciating detail surpassing the limits of human ability to observe them.

As proposed, the term “natural selection” is both vague and enormously large in its proposed scope.  It refers to those things that lead organisms to, and only for example:

- die without leaving offspring, including early deaths before being able to reproduce

- leaving fewer offspring than other members of the same or competing species

- leaving offspring which are less “fit” than the offspring of others, delaying the decline or total failure to leave successful descendants to a later generation

- All of this leading to a progressive decrease in the frequency of the traits common to the unsuccessfully reproducing organism and the eventual extreme rarity or extinction of individuals with that trait in the species, creating new species or the actual extinction of the species another taking “its place” in the geography or environment.

It should go without saying that it also, of course, would have to include those details in the lives of those organisms which are "fit" all of the enormously long and intertwining lines that have produced every single organism alive as you read this.  Organisms are alive as long as they are, their lives continue to have an effect on evolution as long as they are around.

That in itself is a very skimpy and schematic presentation and already it is becoming complex. Consider the first one, organisms dying without leaving offspring.  There are many ways and reasons that can happen.  Birth defects that lead to still birth or death in early infancy, one of those.  And birth defects can be any or several of chemical, environmental or genetic factors or, perhaps injury sustained to the embryo through some mechanical accident.  Each of those possibilities have subsets of differing factors of significantly varied effects.

There are factors leading to early deaths that are not uniform in their fatality but which may or may not be heritable.  Accidents.  Some of those would not be due to any theoretically heritable he factor, no gene for it or even epigenetic whatever, but they might kill off a potentially vital carrier of an unrelated or related trait. [Just as an aside, since traits exist in the same individual, how you could determine them to be unrelated is a puzzle in itself.]  Others would be heritable but would not be uniformly fatal at the age before reproduction.  The number and range of such heritable traits, some passed on but only expressed in combination with genes from the other parent or in certain environmental conditions would effect successful reproduction in individuals carrying them, also effecting the frequency of other genetic traits that are or are not carried by the same individuals.  And those are only the traits that lead to death in early childhood, there are others that express themselves later in life and those which carry advantages in certain climates, such as the trait that makes eating fava beans dangerous but which is  advantageous in areas where malaria is prevalent.   Maybe how tastily fava beans are cooked one day is the life or death issue for that individual's potential offspring.

When you are talking about the evolution of diversity of life on Earth, you have defined an enormously large set of even the first level of categories, those populations we deem to comprise a “species”  or worse, genus or even higher classification.  Individual species have sub-species, based on lesser or more blatantly clear “traits” and traits are not a uniformly definable thing and are not all due to genetic factors.   Even clones have obvious physical variations and they don't lead identical lives.  And reproduction is not done on an individual or a one-to one basis.  Combinations of genetic and other materials (such as venereal diseases) among species add their own multiplying factors to effect timing and rate of death as related to reproduction, successful reproduction and the success of the offspring, and the numbers of offspring.

And organisms don't exist as a schematic chart of one or even all of their genetic traits.  They exist in time, in an environment and habitat all of which are enormously varied and individual.   All of those potentially creating the “fitness” or “unfitness” of individual organisms.  And those environments and habitats aren't static, either.

Combining all of these diverse factors, through addition or multiplication, you soon get to the fact that no two organisms, not even identical twins, will have the same lives,  none will have the same success at reproduction due to combinations of factors you can discern or fail to discern.  It would be impossible to come to a listing of possible combinations.   When you define a scientific field the way that evolution has been defined, including all of these individually complex individuals with their enormously varied characters, circumstances, etc. all in combination with other organisms, those within their own groupings and those outside of them, the ones that want to mate with them or eat them or  kill them as competitors. You've set yourself an impossibly complex task to understand it.

Evolution could be called the mother of all n-factorial problems or it might not be, but that is what it is.

While that fact has the good news for biologists that they will never have nothing left to figure out, that there will be no “end to Biology,”  it does mean that the problem faced makes any claims to have discovered more than the tiniest percentage of information about it massively and absurdly presumptuous.  The idea that Charles Darwin discovered even a definable entity to be natural selection is kind of ridiculous, the history of “natural selection” in intellectual history, the enormous change and variability of what people have taken the term to mean over its 151 years puts the lie to that.  Darwin's proposed mechanism of inheritance didn't even allow his theory to work, that only worked when genetics were rudely plastered to it a half-century after his death, trimming and fitting his theory to match.  And that “synthesis” has undergone extensive alteration in its time as being “natural selection”.  And that doesn't even get to those unobservable, unmeasurable “selective factors” that Lewontin so honestly admitted to.  You can't get to those and include them and their peculiarities in “natural selection”.

If the white-nose disease now endangering entire species of bats in North America was, indeed, introduced by scientists contaminated gear, biological science has certainly been a “selective factor” which could select out the unfortunate bats or radically effect their species.   If people had not desired to write papers on bats, maybe it wouldn't have happened.  Or maybe it was carefree  and thrill seeking spelunkers with no intention to publish.  Just as an example of the enormously diverse and variable conditions contained in the enormously subtle and undefinable term “selective factors”.

That's just the quick and dirty presentation of the problem that I can think of between four and six in the morning on this particular day.   If I had a month I could really come up with problems.

Individual organisms are truly individuals in each and every case, our simplified versions of them, not to mention our abstract make believe ones aren't really there in nature.   In my copy of Lewontin's book, which I lent to my brother yesterday when he saw it on my desk,  he notes Steve Weinberg, the physicist, saying that, "If you've seen one electron, you've seen them all."    Which Lewontin points out isn't true of organisms.  The idea that you can come up with successful statements of the conciseness of physics in biology, reliably applied to each case, is irrational.  Even physics can't entirely define even one electron, exhaustively and comprehensively.

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