Radiation environments

The BBC report on the Chernobyl disaster's effects on wildlife has some interesting features. A lot of species not seen for decades are multiplying. As you might expect, animals can't sense radiation and nest anywhere. Initially things died in the hotspots: trees, horses, mice. But the Red Forest, where all the pines died, is growing back "albeit with stunted and misshapen trees."

"We marked animals then recaptured them again much later," he says. "And we found they lived as long as animals in relatively clean areas." The next step was to take these other mice and put them in an enclosure in the Red Forest. "They felt not very well," Sergey says. "The distinction between the local and newcomer animals was very evident." Mutation In all his research, Sergey has only found one mouse with cancer-like symptoms. He has found ample evidence of DNA mutations, but nothing that affected the animals' physiology or reproductive ability.

Grant that seriously defective critters won't survive long enough to be caught by the researchers. Nevertheless, apparently the survivors live as long as comparable mice not in a radiation environment. At the same time, imported mice don't do well in the radiation area.

To understand why this is interesting, remember that most radiation damage isnot done to the nucleus, but to the rest of the cell. Mutations aren't what kill you, its the damaged proteins that don't work anymore, membranes that leak, and so on.

What this seems to suggest is that one can breed for radiation tolerance. Not radiation immunity--that's no more possible than immunity to fire. Tolerance means that the cell can stand a somewhat larger than usual amount of damage without failure. You might be able to get this by duplication: making extra copies of proteins, for example. This would obviously mean that the mouse would need more food, so this feature would ordinarily be selected against.

It shouldn't be too hard to test: do mice found in the radiation environment have babies that require more food than mice found elsewhere? Grow more slowly on the same diet?

If they were different, then it would be interesting to create a mouse breeding pen with controlled levels of radioactivity. Technically it wouldn't be much of a challenge, though the PR might be a mess.

Update: The researchers did not respond to my inquiries