"Lemmings are small mouse-like animals that live in the tundra. In summer they are brown, but in winter they are all white. Their white coats help them to hide from the snowy owl and other predators who depend upon them for food in winter. Lemmings make simple burrows in the tundra during the summer, and they can make it very difficult to walk around. Especially when you fall through them up to you knees! In winter, they hide from the coldest weather in shallow burrows in the snow.

Lemming populations shrink and swell depending on how many plants and berries are available. One type of lemming, the Scandinavian lemming, migrates in a huge group when food becomes scarce. They will run in one direction through meadows, woods and towns. If they come to a large body of water they will swim and swim looking for land. The stories about lemmings jumping off cliffs are a myth. Other types of lemmings simply move away when the food gets scarce. Wouldn't you?"

read article in full

***

Lasrever: This came from Britannica Online. The person who uploaded the video, elsewhere, wrote: "If all of your friends jumped off the Brooklyn Bridge, would you? If you happen to be a lemming, unfortunately, the answer is a resounding "YES.""

I'm still not sure if the 'cliff suicide' references are true. From what I see in this video they will jump from a high area if there is water below, thinking they can cross, but then drown after paddling aimlessly for awhile.

***

related links:

The Lyre bird can imitate the songs of other birds - not to mention lawnmowers, cameras, buzz saws, and anything else it hears