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Prions Evolve Despite Having No DNA
An anonymous reader writes "Scientists from the Scripps Research Institute have shown for the first time that 'lifeless' organic substances with no genetic material — prions similar to those believed responsible for Mad Cow disease and similar, rare conditions in humans — are capable of evolving just like higher forms of life. The discovery could reshape the definition of life and have revolutionary impacts on how certain diseases are treated."
Not really related, but it is entirely possible for humans to be "alive" in a physical sense even after they are brain dead. As long as they are hooked up to respirators etc., they can be kept alive indefinitely. To date, no human being is ever known to have regained consciousness after brain death.
The _big_ catch here is that most physicians are not properly trained to test for brain death. Most physicians will just see a flat line on an EKG and declare the patient brain dead. I used to work at an organ transplant center, where there were technicians that went through a formal checklist to make sure the patient really is brain dead. It was not uncommon to find patients who did not meet the strict criteria. In the most dramatic example, a 3-yo boy was supposedly brain dead, and he was in the operating room, ready to have his organs removed. The technicians discovered that his pupils did respond to light, so they rushed him out of the OR. On the way back to his room, the boy opened his eyes and smiled. But then he went back into a coma and died 5 days later.
Needless to say, the boy's parents were furious.
Putting the perils of terming new knowledge "obvious" aside, it does seem obvious that evolutionary mechanisms would have to be preexisting for life to have indeed evolved. Since the most generic definitions of life I've seen boil down to providing some form of localized reverse entropy, evolution of the materials of that reverse entropy should be able to happen before the condition itself is actually achieved.
To draw an utterly meaningless comparison, you can certainly have a power supply without a computer, but good luck doing any computing without the power supply. If that makes sense. I should probably cut my breakfast rum down to under 5 shots.