Reply #23: I have the full one page article in front of me and will type the data...

[NNadir]

listing the ratio to controls to wheat grown in the highly contaminated zone. The ratios posted dimensionless numbers are exposed/control frequencies.

Type of variant Ratio to control
Nulls (homozygotes): 1.17
Losses (heterozygotes) 6.45
Losses (homozygotes) 1.88
Gains (Heterozygotes) 2.82
Gains (Homozygotes) 1.34
Heterozygotes losses + gains 3.73
Homozygotes (losses + gains) 1.61.

And the point is?

Well, it seems that there is a natural mutation rate (the existance of which is probably a good thing, or else we would all be bacteria) and the mutation rate resulting from the Chernobyl disaster has indeed lead to one particular species (wheat) suffering genetic mutations faster than they normally do. The authors here point out that the natural mutation rate is estimated at 1.03X10^(-3) for naturally occuring wheat, and 6.63X10^(-3) for Chernobyl exclusion zone wheat.

Note that the Wheat grows, it breeds, and no gross morphological (phenotypical) changes are seen in this single species. It seems pretty clear that many species react differently to radioactivity. In the case of Chernobyl for instance, Scotch pines are definitely doing poorly, whereas birch is proliferating. Presumably wheat has some sort of genetic repair mechanism as do most species so it, unlike Scotch Pine, is able to reproduce after irradiation. My own impression of this paper is that what we have here is more variable Wheat. Since I'm a fan of evolution (both the theory and the physical consequences of the event) I'm really not driven to hysteria about this paper. It has reasonable and unsurprising conclusions: Radiation of wheat increases (but does not create) mutation rates.

Obviously some species do better than others: These nice photographs from inside the exclusion zone (from Dr. Baker's website) show some damaged Scotch Pine Seedlings in a highly contaminated area. (Ignore the swans in the lake near the reactor and the verdant areas surrounding the lake: Some of the scotch pine seedlings are yellowed.) This means that the Viridian Park at Chernobyl long term will probably have a selection pressure in favor of birch.




Here are some other nice pictures from inside the exclusion zone:



Those are some rather pretty mutants.

The original poster entitled "Nuclear Desert" from Dr. Baker's group, who spend quite a bit of time at Chernobyl can be found here:

http://www.nsrl.ttu.edu/chernobyl/posters.htm

It doesn't look like a desert to me, but I might be missing something. I think, of course, is supect the researcher's title for their poster is a somewhat ironic response to the Time magazine cover from the time of the accident that they reproduce therein actual time of the accident.

Failure analysis of Chernobyl is a very important undertaking both from an engineering sense (no one will ever again built commercial graphite moderated positive void power reactors), an administrative sense, (a nuclear power program must be subject to a full, enforced regulatory set of checks and balances that did not exist in the Soviet workers state), and a sober well examined of the ecological consequences of radioactive pollution. I applaud the efforts of the authors of the Nature paper and Dr. Baker, who have done so much to foster clear scientific analysis of this event, a natural laboratory that can help us to make clear, well reasoned decisions about how will try to save a collapsing earth.

I note that mutation rates can rise dramatically from chemotoxic agents as well. With that in mind I will opine that this particular sub-discussion of course does nothing at all to whether nuclear energy is to be preferred to its competitors, since it is a discussion ONLY of a biological effect of a nuclear failure and does not reference in any way the biological effects of OTHER forms of energy. Molecularly planar species such as are created in air pollution, particularly in particulate matter, are well known to interact strongly with nucleic acids. That of course, is the real value of the study with which this thread began: It compares.

One can look at anything in the universe and if one scrutinizes it carefully enough, find something that may be recognized to be pretty scary. This, more than any single feature, is applied to subjects having the word "nuclear" in it, and why nuclear issues are so resistant to critical thinking.

The scientists in the Nature paper have something that the post to which I am responding seems to be untroubled by: A control group. Control groups are what make data meaningful. Without them, in fact, data is completely meaningless.