Since life originated on Earth about 3.8 billion years ago, Pavlov does not believe that there has been enough time for this resistance to evolve.
Foolish. A dose of radiation accumulated over a few days or weeks would not have the same effect as the same dose over a hundred million years. Besides, if that's all it took, all life would exhibit a similar radiation resistance; our cell line certainly reaches back hundreds of millions of years, too. The radiation resistance is most likely the by-product of another evolutionary pressure.
New Scientist sensationalism ping.
Assuming the lethal human dose was the MLD, they got the bugs closer to human survivability, but still short. I'd like to see the raw data before I'm too impressed.
The "mean lethal dose" for humans for a one-time exposure to ionizing radiation is around 300 rads (i.e. 3 Gray), that is, 50% of the humans exposed to such an absorbed dose would be expected to die within thirty days with no medical treatment. While it varies from product to product, a typical absorbed dose for the sterilization of disposable medical products (sutures, surgical kits, operating gowns, catheters, etc.) prior to their delivery to hospitals is around 25 kGy (about 40 million times more than a typical chest X-ray, and over 8,300 times more than the human mean lethal dose). An absorbed dose of around 100 Gray (0.1 kGy) is sufficient to kill most insects and parasites, as well as inhibit plant sprouting (i.e. extend the shelf life of onions, garlic, etc.). Stepping up an order of magnitude, an absorbed dose of around 1.5 kGy --> 4.5 kGy is sufficient to kill most bacterial pathogens (except spores) in foodstuffs such as poultry, beef and spices. For example, a dose of 1.5 kGy will kill about 99.5% (and a 3 kGy dose will kill about 99.99%) of the Salmonella in contaminated poultry (the majority of which is contaminated, incidentally). Similar absorbed dose levels are sufficient for eliminating the danger of bacteria such as E. Coli 0157:H7 and Campylobacter jejune. A slightly higher dose (up to 7 kGy) is allowed for frozen meat. An absorbed dose of around 10 kGy --> 45 kGy is sufficient to inactivate bacterial spores and some viruses. The more resistant spores of Clostridium botulinum (responsible for botulism) necessitate a larger absorbed dose of 30 kGy --> 60 kGy. As previously mentioned, the current required absorbed dose for eliminating the danger of anthrax spores is 56 kGy --> 112 kGy. The US legal limits (both minimum and maximum) for commercial irradiation of various foodstuffs are set forth in Title 21, Volume 3, Parts 170-199 of the Code of Federal Regulations (21CFR3).
They blasted the bugs with enough gamma rays to kill 99.9 per cent of them, let the survivors recover, and then repeated the process. During the first cycle just a hundredth of the lethal human dose was enough to wipe out 99.9 per cent of the bacteria, but after 44 cycles it took 50 times that initial level to kill the same proportion.
Lab-induced evolution bump.
Yep.
Other stuff:
Spider mite upsets evolutionary theory
Haploid sexual species. Interesting.
This doesn't prove evolution. This proves that resistance to radiation follows a lognormal distribution (or something close) within a given population. The article doesn't say anything that I see about that ability being passed on to future generations. Only that harsher treatments on the same set of microbes got diminishing results. Interesting, but it is about mortality in a population, not about whether that is passed along ot future generations. That can be hypothesized, but such a hypothesis is not supported by this data.
--Boot
Unless a colony of the bacteria happened to grow next to a natural pocket of uranium/thorium ore.
If I want sensationalistic hyperbole, I'll pick up the Weekly World News.