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Posts Tagged ‘chromosomal repatterning’

Saltation just means jumping.

Darwin himself was certain that evolution must proceed the same way that the development of cultivars or animal varieties takes place on a farm – inch by inch, each generation producing offspring just barely different from the previous, until the desired improvements are achieved and then locked in place by the wise farmer. Remember also, that he wrote almost 100 years before Watson, Crick, and Rosalind Franklin. He really had no idea even of the cell, let alone the chromosomes or the intricate strand of DNA, so that Behe has written a book, Darwin’s Black Box, titled on that ignorance and its consequences for Darwin’s theory.

The principal evidence that Darwin hoped would verify his theory was expected to be found in the geologic column. The discovery of the long-term fossil sequence was still fairly new in his day; William Smith had already (50 years before) mapped the underside of England and found distinct coal deposits with different fossils; but the changes from one species to another were abrupt, not gradual. This Darwin attributed to the incompleteness of the fossil record, and he was sure it would be remedied over time.

Well, it was not. The sequence remains the same (or similar) everywhere, and so the evidence for a long history of successive life forms is not in doubt, but no full set of minute transitions from one species to a daughter species has yet turned up.

Meantime, almost immediately after Darwin published Origin of Species, Mendel published papers on inheritance that showed its stability and that it was based on specific inheritance factors. When you cross a tall-vined and a short-vined pea plant, you don’t get a medium-height vine; you get some tall and some short. This was a surprise. Darwin was imagining a mushier inheritance, where everything runs together and changes by imperceptible degrees, like a slow change in ocean temperature. For a long time, Mendel’s disturbing paper was just ignored.

In the end, after 40 years of “forgetfulness,” Mendel’s work was resurrected, however, and the neo-Darwinians faced that inheritance is based on little discrete elements, on specific pieces. The new theory located Darwin’s gradual changes in these little pieces (called genes) and taught random variation in the genes. Neo-Darwinism is thus the incorporation of genes into the Darwinian theory.

But single genes still don’t make a species-change, and the geologic record still doesn’t have the imperceptibly gradual changes that Darwin expected and on which he staked his theory. Gene by gene (or at least very gradual) changes are there, but they don’t lead to new species; new species are there, but they arrive quite suddenly. Eventually, Darwinists (still keeping his name) had to content themselves with facing long periods of no evolutionary activity, punctuated by sudden, species-producing jumps. They called this saltation or “punctuated evolution,” which is an oxymoron because it isn’t evolution (gradual change) when nothing is happening, and it isn’t evolution when something dramatic suddenly happens, either.

What is it?

That’s how we come to chromosomal re-patterning.

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Darwinism vs point mutations

Darwinism is the theory that new species arise as a result of

  1. the random accumulation of “point mutations” – that is, individual single mutations at particular points in the strands of DNA that make up an animal’s genome and
  2. the competitive establishment of these new genes which make small changes in body proteins and consequently in body functions. Some of these changed functions help a body and give family members a competitive advantage. They have more or stronger offspring; they take over the world – or at least some niche of it.

All this may be abbreviated as: “random variation and survival of the fittest.”

One point, several points: same-same

A single point mutation does not make a new species, but, say the neo-Darwinists, a sufficient collection does. It is claimed that you need some separation between the old and the developing species so enough changes can collect to make a real difference.

As originally proposed, the theory is dead. Random point mutations do not change species because new species require chromosomal re-patterning. Without such a pattern change, various offspring can mate with fertility, and in that case, they are not a new species. A point mutation does not change the pattern, only one of its elements. A checkerboard is still a checkerboard when one set of squares is gray instead of black. If the second coloration drops out completely, however, then the pattern does change. Or if a third pattern element is superimposed, such as making every third square yellow, then also the pattern is changed and you can’t play checkers. In such a way, the change of a single gene does not make a new species, but a new chromosomal pattern does.

Now, point of logic, please:

If one gene does not change the species, how can two? One gene does not change the species, right? So after this change you have the same species and you change one gene, and that doesn’t change the species either. So if one change doesn’t change the species, then two don’t change the species, and neither do three or four…

Point mutations don’t change a species, not even lots of them accumulating.

Chromosomal re-patterning

One way that chromosomal re-patterning happens is that a whole section of the DNA strand is flipped around and re-attached upside down or in a different place on the strand, or even on a different strand. If (big “If” here!)… If the body pattern resulting from this re-attachment and re-patterning is viable, then it may also be a new species, which does not reproduce with its parent species but breeds true among its siblings.

Thus on my property, I have red maples and silver maples and box elders (ash-leaved maples) and they don’t cross with each other, though they are all maple trees. Apparently, they are real species.

On the other hand, I have had dogs that reproduced with other quite different dogs; in this case, we must be talking about different varieties, not different species, because they all reproduced very successfully.

Now, a glance at what is involved in simple cell division could make it seem a near-miracle (an incredibly unexpected event) that reproduction is ever successful at all. The strands are so delicate, the charges and chemistry so mind-bogglingly ephemeral, the little soup tureen (cell) in which all this must unfold (and re-fold) so crowded! From that point of view, neither a point mutation nor a re-patterning is all that surprising. It makes sense that not every such point mutation would be attractive or helpful to a species, and not every re-patterning would offer a new and viable body plan. But that such changes would arise is fully to be expected.

Darwinism has, more or less, (more among the researchers, less in the textbooks) accommodated these facts. Point mutation is not enough, if only because evolution proceeds in jumps, (saltation) which is what you would expect from chromosomal re-patterning.

If you’re thinking you have no idea what you’d “expect,” from re-patterning think of the set of chromosomes as a blueprint. If you change a room color, same house. If you lift a window from the blueprint and move it over a few feet, the house still won’t change unless you’ve put the window where the support beams go; then the house will collapse; not a viable house plan. If you take the car port and put it in the attic, you have a new pattern, and not a viable one. Change roof for floor: not viable.

Leave the kitchen as is and string out the rest of the rooms in a long row – now it’s a motel, not a house. It’s a new pattern and a viable building plan, but the pattern has changed so it’s not a family home: it’s a new species of building.

So there is a big difference between point mutations, even lots of them, and chromosomal re-patterning, even just once. Point mutations are a relic of old Darwinism and they just don’t square with either logic or the geological record as a way to produce new species. Chromosomal re-patterning could work, and work naturally.

Maybe…

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