Remember lemmings? The rodents that gather to heave themselves (to almost certain doom) off cliffs? It’s a popular myth that these creatures take the leap as part of some strange, Jonestown-esque mass suicide ritual. But in truth, lemmings, which travel in packs, only jump at times of overpopulation – when food is so scarce there is no other option but to dive into the sea in order to search for more sources of food. Well, the good news is that lemmings in Norway haven’t been leaping lately. The bad news: they haven’t been leaping because lemming populations are at a low due to climate change.
Here’s how the BBC breaks it down:
Rather than hibernating, lemmings spend the winter living in the space between the ground and a stable layer of snow above.
Dry winters would allow large numbers to survive until spring, resulting in a population explosion.
But the peak years are not occurring anymore. The research team, composed of Norwegian and French scientists, believes the winters are now too humid, leading to the “wrong kind of snow”.
This results in a less stable subnivean space (the space between the ground and the snow layer above), meaning substantially fewer animals survive until spring.
[Via: BBC]
