Summary Of NI (so far)
According to NI we can distinguish the following processes in the origin and developing of a species:
- Random evolution as described in the Evolution Theory: meaning a very slow process determined by random variations of the DNA of which purely by coincidence one variation represents a better or best fit and so gives a minimal advantage opposite to individuals of the same species without this variation. Examples are the finches of the Galapagos Islands, chimpanzees and bonobo’s and the lighter skin of people living in non-tropical environments. Evolutionary processes according to the Evolution Theory will be able to create new species but (in my opinion) limited to the same family of plants or animals. Geographical circumstances (isolation) to accomplish that are an important if not essential condition. Evolution is limited to the non-focused traits. You may wonder what the function of evolution can be if directional evolution is much quicker and more effective. But the point is that this is limited to the focused trait(s). The non-directional evolution is more flexible. If for instance bacteria become immune against a certain poison, this is probably thanks to this randomness and its flexibility: a few of these bacteria will by coincidence have a mutation that make them resistant. Directional evolution can’t cope with circumstances that are not incorporated in the NI. That also includes non-focused traits that at a certain moment offer the best fit. Evolution may by coincidence find this fit; directional evolution may not. The new species, that are the result of an evolutionary process, may be able to breed with their ancestors but offspring will (possibly) be infertile.
- Directional evolution as part of the NI: meaning a slow process determined by selective, inheritable mutations within the DNA-regions with a higher than random frequency, that in this way is responsible for the focused traits of a species and so its main evolutional direction. These mutations may be triggered by interior or exterior influences (active susceptibility) or may be the result of a more or less continuous higher vulnerability for mutations in these regions (passive susceptibility). This directional evolution is still a quiet slow process but faster than the processes according to the Evolution Theory because a bigger part of the variations in time are in the same direction so will enhance each other. Examples are the steadily growing intelligence of mankind since his/her origin and the growing climbing capacities of apes. Geographical circumstances are usually not essential. Therefor the group, that does not undergo this ‘programmed’ changes or in a slower tempo, has the risk to become extinct. This is what possibly happened to Neanderthals. Directional evolution may not always give the best fit as a whole but only concerning the focused trait(s). Besides that, directional evolution can also implicate restrains or limitations concerning the evolution of certain traits or even block them (and the other way around as is discussed below). This is qualified as negative susceptibility.
- Revolutionary evolution as part of the NI: this is a relatively rapid process, but usually with a noticeable effect only after a longer period of time. During this process one or more of the focused traits will be substituted by one or more new focused traits or will become significantly different (in strength, in susceptibility etc.) or an extra focused trait will be added. This ‘sudden’ change of susceptibility can be a reaction to exterior or interior circumstances (actively, because these circumstances activate certain processes in the bodies of the species) or can be initiated by a coincidental other type of mutation that offers a new inheritable susceptibility for genetic variations that could (in time) give a better fit or another fit (passively) than the existing inheritable susceptibility. A new species (in time), possibly even no longer belonging to the same family of plants or animals, can be the result of this. Existence next to a group of species that did not undergo these changes, is possible or even likely, because the difference in focus becomes so big, that in time there is no decisive competition on an equal level for territory and/or food. So if these processes lead to another fit, existence next to each other is plausible. If the revolution is activated by external circumstances, revolutionary evolution could be the only process that makes it possible for the concerning species to survive in a fast and/or significantly changing environment. Geographical circumstances may be of no interest. In order to make revolutionary evolution work, the basic genetic code of the new trait or of the extra trait already has to be there, so it can be switched on and maybe, if necessary, undergo some internal developments. Interbreeding becomes impossible. An obvious example is apes and mankind as we know them nowadays.
So there are these three processes that together form the evolution of life:
- Evolution is responsible for the origin of new species within one family and with limited differences from existing species, so isolation is likely a condition. It makes it by coincidence possible for a species to evolve and may give, also by coincidence, the possibility to adjust to situations that offer new possibilities or that could be life threatening.
- Directional evolution makes it possible to speed up the evolution over time of a species, concerning a limited number of traits, and maybe even eventually slows it down. Because of this higher speed and the coded direction there is a bigger chance of a successful result (next to ancestors).
- Revolutionary evolution is responsible for the origin of species that differ significantly from existing species or even of the origin of a new family of species. It may give an answer, if life threatening circumstances appear, by directing the evolution of a species in another direction (by coincidence or on purposely) and so could be the most important evolutionary process if a sudden change with a big impact takes place in its biosphere, like during the five periods when mass extinction happened. Directional evolution implies a clear direction in the evolution of one or more of the traits, in which the concerning species excels or eventually may excel, due to a more than random chance of (positive) mutations in the DNA-region(s) which determine(s) this trait or these traits. Therefor directional evolution is (in the long term) the dominant factor in the evolution of a species. It may also include evolutionary restrictions.
Directional evolution implies a clear direction in the evolution of one or more of the traits, in which the concerning species excels or eventually may excel, due to a more than random chance of (positive) mutations in the DNA-region(s) which determine(s) this trait or these traits. Therefor directional evolution is (in the long term) the dominant factor in the evolution of a species. It may also include evolutionary restrictions.
Revolutionary evolution is a fundamental change of the inheritable susceptibility concerning the DNA-region(s) that determine the trait or traits that (primarily) define(s) the species, which can result (if a fit is reached) into a clear change of the directiontional evolution of a species and so may lead to the origin of a new (family of) species.
Note:
In this context a new/other family is defined as a group of animals or plants that have clearly their own directional evolution. Apes and humans may be officially classified as the same family but not in the context of directional evolution. Mules and horses for instance are classified as different species within the same family.
In the NI-theory three (random mutations, inheritable non-random mutations, change of inheritable non-random mutations) evolutionary processes are distinguished. In recent years, also three models have become standard in attempts to understand the nature of evolutionary divergence in fossil lineages: directional change, unbiased random walk, and stasis. Random mutations are of course there but a bit surprisingly also directional changes. Stasis is frequently associated with the theory of punctuated equilibrium, in which most evolutionary changes are concentrated during the (phylogenetic) branching of lineages in very rapid bursts of speciation. Much longer episodes of relative morphological invariance, or stasis, follow the speciation events. Doesn’t that sound a little bit like revolutionary evolution and even like active susceptibility? Is my NI-theory really that new? In a recent article by Hunt this scientist writes that he has found that directional change during the evolution of a lineage is relatively small (occurring only in 5% of 250 analysed traits). Of those traits that were shown to follow a trend, size was more likely to show gradual changes, whereas shape changes were more random. The remaining 95% of sequences were divided nearly equally between random walks and stasis. On this basis the conclusion is drawn that directional evolution is infrequent or, perhaps more importantly, of short enough duration so as to rarely register in paleontological sampling.
Hunt concludes that all three evolutionary processes play a role. So this is according to NI: there are not only random mutations but also other evolutionary processes taking place. Not one process tells the whole storey but three. And in my opinion not next to each other but as a mix. That alone makes the result of only 5% directional changes questionable because how to split these processes and their results? Beside that this article gives no real insight in the evolutionary importance of these 5%. Did they concern the same kind (concerning their importance) of traits as those which changed randomly? Or did they concern traits that were more essential for the evolution of these species? As already indicated maybe not more than 1-2% of all traits may be focused traits. So 5% is in that respect even more than to be expected. Besides that, directional processes deliver faster and better results within fewer steps than a process dictated by coincidences. So the first process produces fewer fossils and a shorter lineage. Has that been taken into account? For me the sentence that directional evolution is _of short enough duration so as to rarely register in paleontological sampling_ for sure not an evidence that it is therefore of less importance. In contrary.
A fundamental difference between NI and the Evolution Theory, as we know it today, is that according to the first theory the essential split happens in the beginning of the origin of a new species (genotype) and the effects of it become clear over a long period of time (genotype and phenotype), while according to the last theory the essential split (genotype) is the end result of a process over a very long period of time (step by step changes). In the first situation the determining genetic split is the cause and in the last situation the determining genetic split is the result. This also implies to my opinion that the Evolution Theory can only lead to the survival of the fittest (in isolated environments) while NI can lead to the same process and result, but can also lead to the ‘survival of another fit’. That possibility is not really incorporated in the Evolution Theory while that for instance can explain, as already indicated, the different evolution of mankind and apes living next to each other in the same environment.
