“Without exception, every animal species studied to date sleeps or engages in something remarkably like it. This includes insects, such as flies, bees, cockroaches, and scorpions; fish, from small perch to the larger sharks; amphibians, such as frogs; and reptiles, like turtles, Komodo dragons, and chameleons. All have a bona fide sleep cycle. Ascend the evolutionary ladder further and we find all types of birds and mammals sleep: from shrews to parrots, kangaroos, polar bears, bats, and, of course, we humans. Sleep is universal.”
These words form a beautiful passage from the book Why We Sleep by Matthew Walker. It hits home on how prevalent the sun has been in the evolution of the natural world. Our sleep-wake cycle is also linked to our internal biological clock which is tied to the cycle of our sun. This is called the circadian rhythm. We have evolved to function in conjunction with the sun. In the rhythms of day and night, summer and winter and so on. Something we don’t always realize in our 24-hour economy and society. With quite some ill effects, to say the least.
Did you know, even worms sleep! And they showed up during the Cambrian period. That makes sleep at least 500 million years old. Even aquatic animals that need to swim all day every day from birth to death, sleep—some actually sleep with half their brain awake and the other half asleep.
As Matthew Walker says, “Mother Nature had no choice. Sleep with both sides of the brain, or sleep with just one side and then switch. Both are possible, but sleep you must. Sleep is non-negotiable.”
Did you know that when birds are alone they sleep with one eye open? One eye open, the other one shut—allowing half their brain to sleep while the other half gets a reboot. A group of birds together sometimes line up in a row. With the birds on the inside enjoying two-eyes-shut whole-brain sleep while the birds on the ends have one eye open and half their brain is asleep. Then halfway through the sleep session, the birds on the end will turn the other direction and shut the other eye to give the other half of their brain some sleep.
I do feel as being like one of those birds on the end of the wire lately. I used to sleep really deeply. But now I always have my ear “open” for the potential cry of my baby daughter. So it has become even more important for me to go to bed on time, this now being 21:00 hrs. Which sometimes I don’t and then regret the next day 😉 Always adjusting and optimizing my habits with loving kindness and a smile.
What is interesting to realize is that sleep itself is universal. But when we sleep, differs. Differs between species but also between people. Some of us are night owls and others are early birds. It all depends on your innate biology, your health type.
After 40 years I learnt that I was actually a night owl that had been living the life of an early bird. By changing my rhythm, I changed my life! Wow-what a difference a day makes! How you time the day, that is.
Are you a night owl or an early bird? Let me know if you are not sure and want to find out. It can make all the difference in the world.
With Love and Energy,