The Darwinian Insight / Molecular Feedback

As Darwin studied the animals of the Galapagos Islands, where he accompanied a British expedition, he was struck by the difference of the species he observed. He saw no evidence that the experience of animals could be inherited. The offspring of an animal that had developed large muscles through vigorous exercise would not be born with larger muscles. But species did gradually change, nonetheless. Darwin hit upon the idea of Natural Selection, that chance “improvements” would become part of the heritance of a species if they made it more likely that a given individual should survive and reproduce. The sum effect of such small steps could over time effect vast changes in the phenomenology of living things.

Feedback

The core insight necessary for evolutionary is that biological feedback of some sort is responsible for not only the proliferation of species, but also the development, over time, of increasingly complex beings (i.e., animals with more complex and more capable nervous systems), culminating in the race of man on our planet. Darwinian Natural Selection is a type of feedback, depending on the survival value of chance mutations. It is, thus, feedback of an intergenerational sort.

The Brain of Man

Hypothesis: Natural Selection alone could not have possibly produced the human brain. Paleoanthropology tells us definitively that the brain of hominids developed into the human brain in about 1 million years, during the period from 1.5 mya (million years ago) to .5 mya. That’s 10,000 centuries. At 5 generations per century, that’s 50,000 generations. Not truly a huge number. And there is no evidence at all that smarter animals reproduced selectively. That is a huge assumption. Some other kind of feedback must have been at work.

Another Sort of Feedback

It has been assumed that there is no way that individual experience (Lamarck) could be transmitted to offspring. That assumption is not necesarily true.

Evolutionary Process

And how about Darwin ?

Charles Darwin and Gregor Mendel came from very different backgrounds, but they were both 19th century naturalists, and they both made great contributions to theories of inheritance. Neither, however, knew anything of DNA and genetic coding. It was Darwin who developed the theory of natural selection, according to which chance mutations can be preserved if they contribute to the likelihood of an organism to reproduce. As far as it went, natural selection was a powerful insight, but it is not enough to explain evolution.

The Basic Process of Evolution: Feedback

At the core of evolutionary process lies biological feedback, a phenomenon we have become used to on many different planes in the natural order. Generalized, feedback is a mechanism for signaling back to a source process something about its effects, so that the process can be modulated or directed. Natural Selection is a type of intergenerational feedback, in that new traits tend to be preserved, to the extent they contribute to the reproductive success of individuals.

Evolution of the Human Brain

The brain of man went through its major development between 3 million years ago and current time. At three million years, the brain was certainly primate, but not particularly distinguished. There was a constant, if not smooth, development thereonward, until the achievement of the modern organ. There is no evidence to support the concept that random mutations could have resulted in any “improvement” at all. “Chance” modifications resulting in greater reproductive success could not have been a sufficient “cause” for the forward march of increasing brain capacity. Other mechanisms need to be considered.

Hypothesis: Molecular Feedback

The modern sciences of genetics, embryology, immunology, and molecular biology have made great strides in elucidating the role of complex molecules in the tranfer of information in different areas of biological function. The hypothesis is made that as “improved” structure and functionality were activated in the brain, through experience, these “advances” were encoded in circulating proteins or nucleosides, which in turn induced “adjustments” in gonadal DNA. This provided a more direct method for transmission of brain “improvements” from generation to generation. This is felt to be consistent with other more clearly established feedback mechanisms.

How Evolution Works

The core of evolutionary process is the ability of an organism to incorporate changes into its genetic makeup. At this point in time, we understand only a portion of the mechanisms involved. It is unlikely that Darwinian Natural Selection accounts for the entire process.

Winning the Lottery

Although their are other aspects to it, the story of human evolution is preeminently the story of the evolution of the conceptualizing, abstracting and judging human brain. The brain, coming from the time of prehuman hominids, had roughly 50 to 100 thousand generations to evolve. If Natural Selection were guiding this process, chance mutations would have had to produce better brain circuits along a highly specific path. This in a relatively small population. The mutations would have had to be dominant, or they would not have been carried forward. And … a highly suspect condition … better thinking would have had to relate to better reproduction … consistently. The advance in ever more complicated brain structure and function was unbelievably complex and biologically sophisticated. Having these advances occur consistently would be akin to winning the lottery at every drawing, against incredibly huge odds. I’m open to being convinced … but I don’t think that’s the way it happened … yet the marvel of the human brain did evolve.

Molecular Informatics

So, if Natural Selection can’t explain evolution entirely, what can?

The answer to that rests, I believe, with an understanding of how the biomolecular systems in the body are capable of handling, processing, and transmitting information. Make it clear: this is hypothetical at this point, though there is plenty of reason for it.