Sudden Origins evolution theory - environmental drama causes mutations

[Dover]

January 31, 2006 at 10 am EST.

An article by University of Pittsburgh Professor of Anthropology Jeffrey H. Schwartz and University of Salerno Professor of Biochemistry Bruno Maresca, published Jan. 30 in the New Anatomist journal, shows that the emerging understanding of cell structure lends strong support to Schwartz's theory of evolution, originally explained in his seminal work, Sudden Origins: Fossils, Genes, and the Emergence of Species (John Wiley & Sons, 2000).

In that book, Schwartz hearkens back to earlier theories that suggest that the Darwinian model of evolution as continual and gradual adaptation to the environment glosses over gaps in the fossil record by assuming the intervening fossils simply have not been found yet. Rather, Schwartz argues, they have not been found because they don't exist, since evolution is not necessarily gradual but often sudden, dramatic expressions of change that began on the cellular level because of radical environmental stressors--like extreme heat, cold, or crowding--years earlier.

Determining the mechanism that causes those delayed expressions of change is Schwartz's major contribution to the evolution of the theory of evolution. The mechanism, the authors explain, is this: Environmental upheaval causes genes to mutate, and those altered genes remain in a recessive state, spreading silently through the population until offspring appear with two copies of the new mutation and change suddenly, seemingly appearing out of thin air. Those changes may be significant and beneficial (like teeth or limbs) or, more likely, kill the organism.

Why does it take an environmental drama to cause mutations? Why don't cells subtly and constantly change in small ways over time, as Darwin suggests?

Cell biologists know the answer: Cells don't like to change and don't do so easily. As Schwartz and Maresca explain: Cells in their ordinary states have suites of molecules-- various kinds of proteins--whose jobs are to eliminate error that might get introduced and derail the functioning of their cell. For instance, some proteins work to keep the cell membrane intact. Other proteins act as chaperones, bringing molecules to their proper locations in the cell, and so on. In short, with that kind of protection from change, it is very difficult for mutations, of whatever kind, to gain a foothold. But extreme stress pushes cells beyond their capacity to produce protective proteins, and then mutation can occur.

This revelation has enormous implications for the notion that organisms routinely change to adapt to the environment. Actually, Schwartz argues, it is the environment that knocks them off their equilibrium and as likely ultimately kills them as changes them. And so they are being rocked by the environment, not adapting to it. ...cont'd

http://www.eurekalert.org/pub_releases/2006-01/uop-ppt012506.php

[ronstratton]

1. sudden evolution theory

If Darwin is correct as many believe, and organisms change and adapt for survival and improvement, why do many people think that humans are above the law of the survival of the fittest?

[qazplm]

5. because we are the first animal

that can radically change and alter our environment to fit us (for better or worse).

Too cold? Build a house with a heat source. Too Hot? Now we can build a house with AC. Little water? We can do irrigation.

So comparatively speaking, we dont face the same harsh environments that the rest of life has had to face up until saipens, neanderthal and a few others came along.

Not to say we are home free. Pollution, global warming, contamination, radiation, supervolcano or comet/asteroid impact can all radically affect even us or eradicate us completely.

[Vinnie From Indy]

2. Would this not be able to be easily tested in a laboratory?

It would seem that this theory could be easily tested by exposing fast reproducing organisms to all manner of environmental change and noting if there are "sudden" mutations rather than gradual.

[benburch]

3. Isn't this, in essence, saltationism?

http://en.wikipedia.org/wiki/Saltationism

[rman]

8. It seems to provide a mechanism for biological saltation

As i understand it, up to now it was just an observed (or perhaps mainly hypothesized) phenomenon.

[Coastie for Truth]

4. Interesting Periodic Discussion in the "Pets" Forum - Maine Coon Cats

Maine Coons are those big boned, heavy weight domestic cats (Same as Norwegians and Russians). Double Coat of Fur, kind of lynx like in appearance, here's a wiki link: . Most vets and breeders will tell you that cold clime "barn cats" develop "Maine Coon" breed characteristics after about ten generations - which is pretty fast considering the inherent stability of the feline genome.

[Phoonzang]

6. Wow, I actually thought of...

...an idea almost identical to this one on my own without having read anything about it. I'm no biologist, but it seems to close the gaps in classical evolution theory, while still preserving the core ideas. I hope that Scwartz's work has been making progress in recent years and isn't, as happens so often, being attacked because it's a new theory that upsets the status quo.

As a previous poster said, I'd imagine this theory would be testable. Take several species, expose them to various environmental stressors, and see if there's a sudden change. Problem is, they don't know what severity of stress is neccesary to induce change and how long it will take.

[Dead_Parrot]

7. Sounds like Punctuated Equilibrium...

...by another name... :shrug:

(Edit: A link might help :))