216 . DASA 2019-2 This ought to be of interest to the geneticists here, ginal exposures were in 1943 or 1944, DONALDSON: started in 1943, Some ofthe ori- Those are the experiments with rainbow trout which WARREN: But here has been the longest, to my knowledge, single set of observations on cne or more species of fish that have been exposed to relatively small amounts of radiation, I think this ought to be continued as long as necessary to get the final answers, [agree with Lauren, He's got some initial answers which loon very spectacular and interesting and he's properly modest in not claiming too much too early. But [think this is as important as following the Nagasaki situation, where the dcsages are not so well controlled. FREMONT-SMITH: It would secrn to me that nature has taken ad- vantage of all of the physical properties of nature aud used them to an advantage. On the other hand, it has been sort of assumed that radiation was always bad and that any radiation was going to be harmful. Now it seems to me there is some evidence to believe that there was a higher radiation in the past than there is today and that it's entirely possible that there is an cptimum radiation for some species, or maybe for many species, and that we shouldn't assume that every radiation is bad, It seems ta me that Lauren's temporary answer supports this position, that it may be that salmon, maybe other fish, and maybe other species are benefited by an appropriate radiation, I knowthis statement is contrary to official position, but I'm contrary to official position, WARREN: I've been looking into this, as you know, with some interest of late and I'm not willing to say that radiatiun is universally harmful because we have a continuous background of naturally occurring radiation and cosmic radiation, The former could have been considerably higher in the past, but I don't think I'm in any position to go aly turther-in that discussion. But I-point to Lauren's experiment as being significant in this direction, _ BRUES: There's recent evidence that the earth's magnetic field flops over every 50 often, letting in meteoric material and cosmic radiation (R -ferencvs 42and 43). I believe the last time that this is supposed to have occurred coincides more or less with the time when man first appeared on earth. That is rather speculative, of course,