Insects Planet

Do Flies Need To Sleep? Let’s Find Out!


Flies are one of the most common insects on the planet, and they are known for their frenzied movements and their love of filth. They are found all over the world and can survive in a variety of habitats.

However, many people want to know if flies actually sleep?

Some believe that flies do not sleep because they are always in motion. However, this is not the case. Flies actually do need to sleep at some point in order to rest and rejuvenate their bodies.

But, their sleep patterns are very different from ours.

How Do We Know That Flies Sleep?

When humans sleep there are two stages, the first is the rapid eye movement (REM) stage which is oscillated with light sleep. The second is non-(REM) stage “deep sleep”.

The flies’ sleep cycle also consists of two stages! In fact, there have been several studies conducted on flies to determine if they sleep.

One of the most famous studies was conducted by the University of Queensland and they discovered that, like humans, flies sleep in stages of different intensities.

They determined that the fly’s sleep alternates between light and deep sleep stages. This was measured by recording the fly’s brain activity and seeing how it responded to mechanical stimuli.

A study, led by Dr. Bart van Alphen found some synaptic connections with cell-to-cell communication were actually strengthened when the fly was awake

When the fly was in a deep sleep they noticed it weakened all the synapses in the brain. They also discovered that when flies learn new pathways during the day they need deeper sleep at night.

So the more flies work they compensate for this by mutating a protein known for weakening synapses in the brain causing the file to sleep more deeply!

Do Flies Sleep With Their Eyes Open?

One thing that sets flies apart from other insects is they have no eyelids. This may seem like a small difference, but it actually has a big impact on how flies live and sleeps.

Without eyelids, flies are constantly bombarded with visual stimuli, which can be overwhelming. As a result, they spend a lot of time rubbing their eyes with their forelegs in an attempt to clean them.

This helps to explain why flies are often seen landing on surfaces before taking off again – they’re trying to get a clearer view by rubbing their eyes!

In addition, the lack of eyelids makes it difficult for flies to sleep, which is why they are always on the move. So, no, flies do not have eyelids so they cannot close their eyes to sleep.

Signs That A Fly Is Asleep:

  • Flies Will Often Stop Moving And Perch
  • Their Legs Will Be Drawn Up Close To Their Body
  • They Maybe Drooping In The Direction Of Gravity

How Long Do Flies Sleep For?

Have you ever wondered how those pesky flies sleep? Well, as it turns they don’t follow the same pattern as humans. For example, while we sleep for eight hours straight, flies take several short naps throughout the day.

Take Note: Studies have shown that fruit flies can sleep anywhere between 400 and 1100 minutes per day all of which are taken in separate naps. While the duration of each nap may be short, they make up for it by taking a lot of naps!

Do Flies Sleep Day Or Night?

Flies like the common house and, bottle flies, are most active during the day, so they typically sleep at night. However, there are some species of flies that are active at night and sleep during the day.

This is mainly because flies need light in order to guide them visually. However, at night when temperatures drop, flies and there is no light, these flies will enter a state of sleep.

In this state, the fly’s metabolism slows down and they can even enter a state of hibernation. This helps them to conserve energy until the sun comes up and they can become active again.

Does The Temperature Affect Their Sleep?

Yes, it can! Flies are affected by temperature in fact, if the temperature falls below 45 degrees flies become inactive. Flies will usually thrive in hot climates, however, in cold climates flies will die off.

When it’s cold outside, you might see a fly trying to find its way into your home. This is because they are looking for a warm place to sleep!

Where Do Flies Go When They Sleep?

Do you ever wonder where flies sleep? It may seem like a silly question, but it’s actually a bit of a mystery. Because flies take short naps they can sleep anywhere.

However, when it comes to finding a safe place to sleep, flies are just like us they want to be in a comfortable and protected place. For example, they wouldn’t sleep close to a spider’s web or any insects that would see flies as a devious meal.

This is why you often see flies taking shelter in dark corners or under eaves. As long as they are away from predators and the elements, they can sleep anywhere.

Why Do flies Sleep On The Ceiling?

One of the most puzzling behaviors of flies is their tendency to sleep upside down. While the reasons behind this behavior are still not fully understood, there are a few theories that offer some insight.

One possibility is that they are attracted to light which is why the fly ends up on the ceiling and is taking a quick nap. Another theory of why they are sleeping upside down helps flies to stay cool.

By hanging from the ceiling, they are less likely to come into contact with warm surfaces, which can help them to avoid being overheated.

Another theory is that sleeping upside down provides flies with a better vantage point for being spotted by predators or other potential threats. By hanging from the ceiling, they can keep a lookout for danger while they rest.

Regardless of the reason, it’s clear that flies have evolved to take advantage of this unique sleeping position.

What Happens If They Don’t Get Any Sleep?

Now that we know a bit more about how and where flies sleep, you might be wondering what happens if they don’t get any sleep. It’s actually pretty serious!

If flies don’t get enough sleep, it can affect their memory, learning, and ability to fly. This can cause them to make mistakes and put themselves in danger and in extreme cases, it can even lead to death.


So there you have it! Now you know everything there is to know about how flies sleep. Next time you see one taking a nap, you’ll know exactly what’s going on! Thanks for reading!

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