Pity the lemming

The Weathermakers by Tim Flannery, p. 99:

Collared lemmings are the true offspring of the extreme north, for they survive even on the hostile northern coast of Greenland, and are superbly adapted to life in the cryosphere... Their population fluctuates on a cycle of around four years, at the end of which their abundance is such that they may migrate en masse in search of food, thereby giving rise to the idea, erroneously propagated, that they commit suicide by running off cliffs...

...if global warming trends persist, forests will expand northwards to the edge of the Arctic Sea destroying the tundra... For the collared lemming the tundra and life itself are inseparable, and the report states that the species will be extinct before the end of this century. Perhaps all that will be left then will be a folk memory of a small, suicidal rodent. But the real tragedy will be that the lemmings didn't jump. They were pushed.