Feedback Loops, One-Eyed Thinking and Turbo-Charged Selection

Put on your thinking caps!

That's an idiomatic expression used by American schoolteachers to encourage children to give careful consideration to a particular problem.

Feedback Loops 

The standard version of the Neo-Darwinian theory of Bilaterian evolution asserts—implicitly but emphatically—that  during the ~550 million years of Bilaterian history there was no need for a  feedback loop connecting the smallest components of the developing animals—the individual somatic cells—to the entities controlling the production of those cells—the evolving gene pools. My proposed major additive amendment to that theory asserts, to the contrary, that because of the spectacular complexity found throughout the Bilateria and the exquisite precision of cellular construction evident during development of all individual specimens, a theory pretending to explain their existence demands it. I have concluded that such a feedback loop has existed since the origin of the Ur-Bilaterians and that it has played a critical, central role throughout evolutionary time. 

Feedback was initiated by lethal juvenile cancer, a process that began in a single somatic cell, a cell that had been imperfectly developed. We can assert that the pre-malignant cell—at a point in time concurrent with (or immediately prior to) its transformation to the cancerous state—was always maldeveloped; carcinogens are mutagens and mutagens are carcinogens. (1) Cancer never begins in perfectly-formed cells.

A Prohibited Animal

According to Karl R. Popper, in comparing two competing theories, the one that forbids more occurrences in the natural world—that lists more possible refutations—is superior to one that forbids fewer. (1)

In Chapter Thirteen of Cancer Selection I describe three separate and distinct refutations of my proposed fundamental amendment to the neo-Darwinian theory of evolution. In one refutation I describe an imaginary animal, one that possesses a constellation of particular characteristics, each one of which can be found in abundance in Nature, and assert that such an animal cannot exist; find one forbidden specimen and my theory is refuted.

Who Has Been Visiting This Site?

Now that the site has accumulated a few thousand page-views, it might be interesting to view a summary of visitors' geographic location.

    USA                               57.4%
    Russia                           10.8
    Germany                      10.6
    France                             4.8
    United Kingdom             4.0
    Ukraine                           4.0
    China                              4.0
    All Other                         4.4 
    
    Total                           100.0%

On the Origin of Bilateral Symmetry

It is a fundamental principle of evolutionary theory that Nature never anticipates. A gene pool cannot plan for changes in the environment, for the possible future emergence of new predators or any other contingency; the existential threats any gene pool ever encountered existed in the here-and-now. In this posting I propose that bilateral symmetry was originally selected, not for its future mobility-enhancing potential, but because it functioned as a cancer-preventing device in the earliest Bilaterians. 

Those familiar with my published theory know it asserts that all multicells can be divided into two mega-groups: those constructed of somatic cells which all contained functioning cancer triggers (oncogenes) and those that were incapable of dying of cancer. As my peer-reviewed 1984 Letter in the Journal of Theoretical Biology stated succinctly, "This theory states that oncogenes, thus defined, have been present in every cell of every specimen of every species of the Bilateria that ever existed, and that they have existed nowhere else in Nature."

My 1983 Letter asserted that evolutionarily significant lethal cancer did occur in developing Bilaterians in numbers sufficient to create selection pressure for the accumulation of anti-cancer mechanisms and, because cancer begins with replication error, that all those defenses " ... enhanced the ability of the genomes to create organisms in which the genetic program is expressed with great fidelity in all somatic cells." (1)
 

I am convinced that one of the earliest anti-cancer adaptations was rejection of the radial symmetry found in other multicells (including the likely ancestors of Bilaterians) and selection of symmetry along a longitudinal axis, a radical departure that enabled gene pools to produce sufficient numbers of animals free of cancer during development.

Cancer Discovered in Hydra?

It has recently been reported here and here that scientists at Kiel University in Germany claim that cancer has been found in Hydra.

Anyone familiar with my published theory knows it asserts that lethal juvenile cancer occurred in all Bilaterians and only in Bilaterians, that other multicells including cnidarians like Hydra did not experience it during evolution.

So does this report from Kiel University conflict with my theory?