Chapter 119 19.8 DNA does not encode everything

The developmental process of the egg cell is burdened with too much inherited baggage, which limits the possible diversity of its adult body.In general, the matter that makes up the body uses physical constraints to limit the forms into which the body can develop.Elephants cannot have legs as thin as ants.The physical nature of genes also limits the kinds of animals that animals can form.Each piece of genetic information is a protein molecule that must be transmitted by physical movement.Due to these physical constraints of genes, it is difficult or impossible for some information to be encoded in a complex body, and the same is true for DNA.

Genes have dynamic characteristics independent of the body, and they have the right to life or death over their output.Within the genome, genes are interrelated so that they are interlocked: A presupposes B, B presupposes C, and C presupposes A.This interconnection forms a conservation force that forces the genome to remain unchanged—regardless of the body it was born from.Like complex systems, genomes resist perturbations by limiting the changes allowed, in pursuit of survival as a cohesive unity. Correlated properties in the genome come into play when artificial or natural selection drives a genotype (say, that of a pigeon) away from a steady state toward one's own preferences (say, white), This has many side effects (for example, nearsightedness).Darwin, as a pigeon breeder, had noticed this and called it "the mysterious law of correlation in growth".Ernst Mayer, the patriarch of neo-Darwinism, claimed: "As far as I know, there is not a single case of careful selection (breeding) experiments carried out in the past 50 years without unpleasant side effects." By traditional groups Single-point mutations, on which genetics is the bedrock, are actually very rare.Genes are usually in a complex environment, and they themselves are a complex adaptive system with their own intelligence and inertia.This is the reason why there is truth in strangeness.

Genomes have to deviate far enough from their usual configurations to make a substantial difference in appearance.When the genome is pulled out of its normal orbit by competing pressures, it must physically reorganize its association patterns in order to maintain stability.In the words of cybernetics, it must make itself fall into another attractive field with integrity, restraint and internal stability. Before organisms came into existence, before they faced the natural selection of competition and survival, they were already subject to their internal selection twice-one from the internal constraints of the genome, and the other from the laws obeyed by the body.Before an organism really engages with natural selection, it also faces internal selection from a third dimension.A change that is accepted by the genes, and subsequently by the body, must also be accepted by the population.A mutation that only occurs in a single body, no matter how outstanding it is, will inevitably disappear with the death of the single body.Unless the gene containing the mutation is able to spread throughout the population.The population (or the same group) has its own restraint and integrity, and presents an overall emergent behavior, as if it is a huge and internally stable system—the population is the individual.

Anything new that evolves across these hurdles is awe-inspiring.In Towards a New Philosophy of Biology, Meier writes: "The hardest feat of evolution is breaking free from this restraint. That is why so few new species have appeared in the past half a billion years." ; moreover, the fact that 99.999% of evolutionary clades have become extinct is also likely to be involved. This restraint prevents species from responding quickly to sudden changes in the environment.” Evolutionary stagnation in a constantly changing, co-evolving world The phenomenon was once very confusing to people, and now there is finally a decent explanation.

The reason why I delve into these cases is because the constraints on biological evolution are also the promise of artificial evolution.Every negative constraint in evolutionary dynamics can be viewed positively.The binding forces used to sustain old traditions can be used to create new ones.The same force that confines a creature to its own form, preventing it from drifting at will into other forms, is also the same force that gave shape to a creature in the first place.This self-reinforcing nature within the gene makes it difficult to leave its stable state, like a valley into which random factors are pulled until they find a possible shelter.Over millions of years, multiple stabilities of genomes and bodies maintain the centripetal state of species, acting more than natural selection.And when a species makes a leap out of its old homeostasis, the same introversion lures it into a new homeostasis—still with minimal influence from natural selection.This may seem strange at first glance, but it is true that to bind is to create.

As the saying goes, "failure is also bound, and success is also bound."Introversion rather than natural selection that emerges at different levels of biology is likely to be the reason for the origin of 99.999% of life forms.We can't yet measure the role of tethering in forming life—what some call "self-organization"—but it's likely to be huge.