Evolution Research - General Evolution News

(Jeffrey H. Schwartz and Bruno Maresca's approach is consistent with a proposed testable 'Model of an Internal Evolutionary Mechanism' based on an extension to homeostasis - see [2])

Summary: Jeffrey H. Schwartz's most recent article, "Critique of Molecular Systematics," is the next step towards a counter evolutionary theory that takes a critical look at the theory of cellular and molecular change.

Pittsburgh - Jeffrey H. Schwartz, University of Pittsburgh professor of anthropology in the School of Arts and Sciences, is working to debunk a major tenet of Darwinian evolution. Schwartz believes that evolutionary changes occur suddenly as opposed to the Darwinian model of evolution, which is characterized by gradual and constant change. Among other scientific observations, gaps in the fossil record could bolster Schwartz's theory because, for Schwartz, there is no "missing link."

In an examination that further challenges the Darwinian model, Schwartz and cowriter Bruno Maresca, a professor of biochemistry at the University of Salerno, Italy, examine the history and development of what the writers dub the "Molecular Assumption" (MA) in the article "Do Molecular Clocks Run at All? A Critique of Molecular Systematics," [1] to be published in the Febuary 9 issue of Biological Theory. [Molecular Clock]

The MA became a veritable scientific theory when, in 1962, biochemists Emil Zuckerkandl and Linus Pauling demonstrated species similarity through utilizing immunological activity between the blood's serum and a constructed antiserum. Upon observing the intensity of the serum and antiserum reactivity between human, gorilla, horse, chicken, and fish blood, Zuckerkandl and Pauling deduced "special relatedness"-the more intense the reaction, the more closely related the species were supposed to be.

Fish blood was most dissimilar, so it was assumed that the fish line diverged long before the other species. Human and gorilla blood were the most similar, meaning both species had the least amount of time to diverge. Ultimately, the Darwinian model of constant evolutionary change was imposed upon the static observation made by Zuckerkandl and Pauling.

To date, the scientific community has accepted the MA as a scientific truth. It is this assumption, which Schwartz is contemplating: "That always struck me as being a very odd thing-that this model of constant change was never challenged." Schwartz has his own theories regarding evolution, which are backed by recent developments in molecular biology.

Multicellular animals have large sections of genomes, the genetic material of an organism, which control their development. Schwartz argues that the structure of the genome does not keep changing, based on the presence of stress proteins, also known as heat shock proteins. These proteins are located in each cell, and their main function is to eliminate the potential for cellular error and change via maintaining normal cellular form through protein folding.

This regular cellular maintenance is what Schwartz points to regarding his refutation of constant cellular change. "The biology of the cell seems to run contrary to the model people have in their heads," says Schwartz, and he contends that if our molecules were constantly changing, it would threaten proper survival, and strange animals would be rapidly emerging all over the world. Consequentially, Schwartz argues that molecular change is brought about only by significant environmental stressors, such as rapid temperature change, severe dietary change, or even physical crowding.

If an organism's stress proteins are unable to cope with a significant change, the genomic structure can be modified. However, Schwartz notes, a mutation also can be recessive in an organism for many generations before it is displayed in its offspring. Whether or not the offspring survives is another matter. If it does in fact live, the presence of this genetically modified organism is not the product of gradual molecular change but a sudden display of the genetic mutation, which may have occurred myriad years prior.

However, it is not only the current molecular theory that intrigues Schwartz, but the failure of the scientific community to question an idea that is more than 40 years old: "The history of organ life is undemonstrable; we cannot prove a whole lot in evolutionary biology, and our findings will always be hypothesis. There is one true evolutionary history of life, and whether we will actually ever know it is not likely. Most importantly, we have to think about questioning underlying assumptions, whether we are dealing with molecules or anything else," says Schwartz.

Schwartz, who forensically reconstructed three life-size images of George Washington that are on display at Mt. Vernon, is a Fellow of the prestigious American Association for the Advancement of Science and the World Academy of Art and Science. He is the author of several books, including "The Red Ape: Orang-utans & Human Origins" (Westview Press, 2005) and "Sudden Origins: Fossils, Genes, and the Emergence of Species" (Wiley, 2000). He has spent more than 20 years contemplating the methods, theories, and philosophy of taking data and trying to interpret it for purposes of reconstructing evolutionary relationships.

Source: University of Pittsburgh News February 9, 2007

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[1] "Do Molecular Clocks Run at All? A Critique of Molecular Systematics,"
Jeffrey H. Schwartz and Bruno Maresca

Currently available as a PDF file from Orangutans and human origins at the Buffalo Museum of Science.

Abstract

Although molecular systematists may use the terminology of cladism, claiming that the reconstruction of phylogenetic relationships is based on shared derived states (synapomorphies), the latter is not the case. Rather, molecular systematics is (largely) based on the assumption, first clearly articulated by Zuckerkandl and Pauling (1962), that degree of overall similarity reflects degree of relatedness. This assumption derives from interpreting molecular similarity (or dissimilarity) between taxa in the context of a Darwinian model of continual and gradual change. Review of the history of molecular systematics and its claims in the context of molecular biology reveals that there is no basis for the "molecular assumption."

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[2] Maresca, Bruno and Schwartz, Jeffrey H.
(2006) "Sudden Origins: a general mechanism of evolution based on stress protein concentration and rapid environmental change." The Anatomical Record, Part B: The New Anatomist, Vol. 289B: 38-46.

Abstract

A major theme in Darwinian evolutionary theory is that novelty arises through a process in which organisms and their features are gradually transformed. Morgan provided Darwinism and the evolutionary synthesis with the idea that minor mutations produce the minuscule morphological variations on which natural selection then acts, and that, although mutation is random, once a process of gradual genetic modification begins, it becomes directional and leads to morphological, and consequently organismal, transformation. In contrast, studies on the role of cell membrane physical states in regulating the expression of stress proteins in response to environmental shifts indicate the existence of a downstream mechanism that prevents or corrects genetic change (i.e., maintains "DNA homeostasis") (homeostasis). However, episodic spikes in various kinds of environmental stress that exceed an organism's cells' thresholds for expression of proper amounts of stress proteins responsible for protein folding (including stochastically occurring DNA repair) may increase mutation rate and genetic change, which in turn will alter the pattern of gene expression during development. If severe stress disrupts DNA homeostasis during meiosis (gametogenesis), this could allow for the appearance of significant mutational events that would otherwise be corrected or suppressed. In evolutionary terms, extreme spikes in environmental stress make possible the emergence of new genetic and consequent developmental and epigenetic networks, and thus also the emergence of potentially new morphological traits, without invoking geographic or other isolating mechanisms.

See "The Internal Evolutionary Mechanism: Basic Concept" (blog post - includes fibonacci analogy) and "Model of an Internal Evolutionary Mechanism" (original webpages).

And:

"An Error In Associating Lamarck With 'Adaptive Mutations'?"

"Why research an 'Internal Evolutionary Mechanism'? (1)"

"An Internal Evolutionary Mechanism and 'Direction in Evolution': Preliminary Notes"

"Common objections to 'Internal Evolutionary Mechanisms' (1)"

"Researcher gives hard thoughts on soft inheritance"

"Mother's Diet during Pregnancy can affect Grandchildren (Epigenetics)"

"'New Science' to be created at Florida State University Workshop"

"Evolution's 'Driving Force' Shifts Based on Behavior, Study Says"

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