Mutations & New Body Plans

Explore Evolution claims:

According to Neo-Darwinism, new biological form arises when natural selection acts on randomly occurring mutations and variations in DNA. But new research seeems to say that mutations in DNA assembly instructions will produce, at best, a new protein. Higher-level instructions for building tissues, organs and body types are not stored only in DNA. This means that you can mutate DNA 'til the cows come home and you still wouldn't get a new body plan.
Explore Evolution, p. 111

It is outright baffling that Explore Evolution cites Franklin Harold's book, The Way of the Cell, to support the claim that mutations are insufficient to change body plans. Franklin Harold is a microbiologist, and a proponent of the role of self-organization and structural constraints in the spatial organization of cells and does not remotely address the issue of body plans in his book. He's interested in microbes, not higher organisms.

This book celebrates microorganisms, and that requires explanation because with most folks the word "life" does not conjure up the image of a bacteria or protozoa Microorganisms, the bacteria and protists, can make a biosphere all by themselves, and did so for billions of years when the earth was young. Higher organisms hold mysteries that are of special concern to us humans; the genetic basis of disease, the immune response, embryonic development and the nature of mind are now at the forefront of the research effort. But for the purposes of an inquiry into the nature of life, these are peripheral issues. They represent potentialities inherent in living matter, but they are not required for its existence.
Franklin Harold (2001) The Way of the Cell, Preface, p. xi

Nor is Franklin Harold sympathetic to the special pleading that a mysterious "something else" is needed to explain cellular morphology.

Spatial organization is not written out in the genetic blueprint; it emerges from the interplay of genetically specified molecules, by way of a hierarchy of self-organizing processes, constrained by heritable structures, membranes in particular.
Franklin Harold (2005) Molecules into Cells: Specifying Spatial Architecture, Microbiology and Molecular Biology Reviews, 69 p. 545

Perhaps Explore Evolution meant to include reference 21, Stephen Meyer's paper, "The origin of biological information and the higher taxonomic categories," which was later retracted by the Proceedings of the Biological Society of Washington.

During the Cambrian, many novel animal forms and body plans (representing new phyla, subphyla and classes) arose in a geologically brief period of time. The following information-based analysis of the Cambrian explosion will support the claim of recent authors such as Muller and Newman that the mechanism of selection and genetic mutation does not constitute an adequate causal explanation of the origination of biological form in the higher taxonomic groups.
S. Meyer (2004) "Origins of Biological Information and the Higher Taxonomic Categories," Proceedings of the Biological Society of Washington 117(2):213-239

As in Explore Evolution, Meyer refers to Origination of Organismal Form for support. But, as described elsewhere in this critique, Muller and Newman are not addressing the origin of higher taxonomic categories per se, they are concerned with the origin of the forms of the earliest multi-cellular life and of their embryos.

However, Simon Conway Morris, a paleontoloist who studies Cambrian and pre-Cambrian fossils, does address the issue of body plans in the Origination of Organismal Form:

Despite the seeming welter of body plans emerging in the Cambrian, it is difficult to escape the conclusion that the process and products, far from requiring a radical revision of existing theory, fit comfortably into the neo-Darwinian framework.
S.C. Morris (2003) "Metazoan Phylogeny," in Origination of Organismal Form,, p. 21

The vibrant field of evolutionary developmental biology has generated significant insights into the mechanisms by which mutations in DNA would have generated the morphological novelty that produces tissues, organs, and body types. The only citation the authors offer to support their beliefs to the contrary turns out not to support the claim by Explore Evolution.

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