Have you ever asked yourself why we need to sleep, how much sleep is necessary or whether elephants sleep lying down or standing up? Have a look at these weird and wonderful sleep facts:
- As well as being the name of a famous band, REM stands for “rapid eye movement”, so called because our eyes can be seen to move under our eyelids.
- REM sleep starts about 90 minutes after we fall asleep and occurs in bursts throughout the night, adding up to around 2 hours per night in total.
- During REM sleep we are almost totally paralysed. Only the heart, diaphragm and muscles of the intestines, blood and eyes are not affected by this paralysis.
Creatures of the night
- Elephants sleep lying down during REM sleep but stand up during non-REM sleep!
- It’s not known for sure which animals besides humans dream, if any.
- Monkeys, chimps and other primates all sleep for about 10 hours a night and on average we humans sleep three hours less than this. Apart from teenagers that is, who also tend to sleep for 10 hours.
- Both dolphins and ducks can keep one half of the brain awake while the other half sleeps; so that they are always prepared for predators.
- The phrase ‘cat nap’ refers to a quick doze, but in fact cats actually sleep for about 12 hours a day.
- We humans need to sleep for a good eight hours, whereas giraffes only need to sleep for about two hours a day.
- Armadillos sleep for an average of 18.5 hours a day.
- Fish cannot close their eyes to sleep because they have no eyelids. In fact, it is not really known if fish sleep at all.
Look at the following photos of unusual beds and maybe you could let us know the most unusual place you’ve slept in!
- Practise your vocabulary on sleep by doing this test.
- Here are seven ’sleep’ idioms and expressions in English.
1. to sleep like a log
Meaning: to sleep very deeply without waking up for a long time
Example: I was so tired after running five miles yesterday that I slept like a log.
2. to sleep on it
Meaning: to take a night to make a decision
Example: I’m really not sure whether to buy your car or not. Do you mind if I sleep on it and let you know tomorrow?
3. a sleeping giant
Meaning: something very powerful that is currently inactive
Example: Indonesia has vast natural resources and has often been considered a sleeping giant by experts on South-East Asia.
4. not sleep a wink
Meaning: to not sleep at all
Example: The neighbours had a really loud party last night and I didn’t sleep a wink.
5. to lose sleep over (something)
Meaning: to be worried about something
Example: We need to finish this project by Saturday but try not to lose sleep over it, we have plenty of time to work on it over the next two days.
6. fast / sound asleep
Meaning: to be fully asleep and not easy to wake up
Example: My daughter is fast asleep by 1pm every afternoon.
7. sleep in
Meaning: to stay asleep until later in the day than you normally would
Example: I like to sleep in on Saturdays. I don’t have to go to work so I can sleep in until 9am.
- Here is a text from the British Council site called What are dreams for? to listen to and an activity to do.
Finally, here are a couple of songs: