PROFESSOR (Canadian): It’s a common myth that animals spend most of their time sleeping. This is an especially common belief about pets such as cats and dogs. But while there’s some truth to the fact that domesticated animals have a lot of time to lounge around, that’s not necessarily representative of the sleep patterns of animals in general. As we’re doing a survey of the animal kingdom in this course, I thought it would be a nice break from the routine to stop and debunk some of these animal sleep myths.
Let’s start with cats, since they probably have the worst rap of all when it comes to sleep. Um, it’s not just house cats that are thought to sleep excessively, but the big ones, like lions and tigers. The rumour is that they are only awake for about four hours per day. But in fact, a study of lions in South Africa showed that they are resting for an average of 14 hours per day. Lions, just like domesticated cats, are cathemeral, meaning that they take short, sporadic naps throughout the day and night. When they added up the hours of actual sleep for over 200 lions, they found that it was far less than the myth suggests.
In fact, it’s actually brown bats that win the prize for the most sleep. Those little guys can spend up to 20 hours of their days dozing off. Ironically, the larger animals such as giraffes and elephants need the least sleep, only four hours each night. Even though that seems counterintuitive, it has been well documented in academic literature.
Here’s another one that cracks me up…that albatrosses sleep while flying. I think this idea got started because albatrosses fly long distances, covering thousands of kilometers over the open sea before touching down on land. So people just assumed that they must sleep while in flight. But a recent study revealed that it’s actually more likely that many birds have evolved to be able to go without sleep for extended periods of time.
Uh, I’ve also heard many people claim that whales can dream just as humans. Well, not exactly. Whales are certainly intelligent creatures, and their communication capacity far exceeds most animals. However, if whales were able to dream, this would mean that they would have to enter the REM phase, the deepest phase, of sleep. But marine mammals don’t enter REM because they require regular muscle movement to return to the surface for air. Some researchers think it’s possible that whales do enter REM for very brief periods of time. But even if such were the case, it would likely last for minutes at the most. Hardly enough time to dream.