Do Cicadas Sleep? An Investigation into the Sleep Habits of These Nocturnal Insects

Cicadas are fascinating creatures that have captured the attention of humans for centuries. They are famous for their loud, buzzing calls, which fill the air with a deafening symphony during the summer months. But have you ever wondered if cicadas sleep? After all, they are nocturnal insects, so they must rest at some point. In this article, we will delve into the world of cicada behavior to answer this intriguing question.

Understanding Cicada Behavior

To understand if cicadas sleep, we must first explore their behavior. Cicadas are insects that belong to the family Cicadidae, and there are more than 3,000 species of cicadas worldwide. They are known for their long life cycle, which can last up to 17 years in some species. Cicadas are also nocturnal insects, meaning they are most active at night.

The Life Cycle of Cicadas

Cicadas go through several stages of development, including egg, nymph, and adult. The adult cicada is the most well-known stage, as this is when they emerge from the ground to mate and lay their eggs. Cicadas live for several weeks as adults, and during this time, they are most active at night.

When cicadas first emerge from the ground, they are not yet fully developed. They must undergo a process of molting, where they shed their skin several times before reaching maturity. This process can take several weeks, during which time the cicadas are vulnerable to predators and other threats.

Nocturnal vs. Diurnal Insects

While some insects are active during the day, known as diurnal insects, cicadas are nocturnal insects. This means that they are most active at night and spend the day resting or sleeping. But what exactly is sleep in insects?

Scientists have found that insects do exhibit behaviors that are similar to sleep in humans and other animals. For example, some insects have been observed to have periods of inactivity or reduced movement, which could be a form of sleep.

However, it is important to note that the sleep patterns of insects are not well understood, and more research is needed to determine exactly how and why insects sleep.

The Role of Sound in Cicada Communication

Cicadas are famous for their loud buzzing calls, which can reach up to 120 decibels in some species. These calls serve a vital role in cicada communication, as they are used to attract mates and establish territory. Cicadas produce these calls by vibrating their tymbals, which are organs located on their abdomen.

Interestingly, cicadas are not the only insects that use sound to communicate. Many other insects, such as crickets and katydids, also produce sounds to attract mates or defend their territory.

Scientists have also found that cicadas have a unique ability to synchronize their calls with other cicadas in their vicinity. This synchronization is thought to help cicadas attract mates more effectively and avoid competition with other males.

In conclusion, while the sleep patterns of cicadas and other insects are not well understood, their behavior and communication methods are fascinating topics of study for scientists and nature enthusiasts alike.

Defining Sleep in Insects

To determine if cicadas sleep, we must first define what sleep is in insects. In humans, sleep is characterized by a decreased level of consciousness and bodily activity, as well as increased brain activity during rapid eye movement (REM) sleep. However, insects have a much simpler nervous system than humans, and their behavior is not as complex.

The Science of Insect Sleep

Scientists have identified periods of decreased activity in many insects, which they refer to as rest or sleep. During these periods, insects may exhibit decreased movement, increased arousal threshold, and increased sleep-like behaviors.

For example, some insects may exhibit a decreased response to stimuli during periods of rest, similar to humans experiencing slow-wave sleep. Other insects may exhibit a quiescent state, where they remain motionless for extended periods of time, similar to humans experiencing deep sleep.

Comparing Insect Sleep to Human Sleep

While insect sleep is not as complex as human sleep, there are some similarities. For example, both insects and humans exhibit a circadian rhythm, which is a natural cycle of wakefulness and sleepiness that follows a 24-hour pattern. Insects also show changes in brain activity during periods of rest, similar to humans.

However, there are also significant differences between insect and human sleep. Insects do not experience REM sleep, and their sleep patterns are often much shorter than humans, sometimes lasting only a few minutes at a time.

Factors Affecting Insect Sleep Patterns

Many factors can affect insect sleep patterns, including temperature, light, and humidity. Insects may sleep less during periods of extreme heat or cold, while increased light exposure can disrupt their natural sleep patterns.

Additionally, some studies suggest that social factors can also affect insect sleep patterns. For example, ants have been observed to sleep less when they are in the presence of other ants, possibly due to increased levels of activity and communication within the colony.

Overall, while insect sleep may not be as complex as human sleep, it is still an important area of study for understanding the behavior and physiology of these fascinating creatures.

The Sleep Habits of Cicadas

So, do cicadas sleep? The answer is yes, but their sleep habits are quite different from those of humans. While cicadas do rest, they do not experience the same level of consciousness as humans. Their rest periods are characterized by decreased activity, decreased responsiveness to stimuli, and a reduced metabolism.

Observations of Cicada Sleep

Scientists have observed cicadas resting during the day, often clinging to a tree or other surface with their legs. During these periods, the cicada may appear motionless, but if disturbed, they will quickly move away.

It is interesting to note that cicadas have a unique way of sleeping. Unlike humans, cicadas do not have eyelids to close. Instead, they have a transparent third eyelid, called a “nictitating membrane,” which covers their eyes while they rest. This membrane protects their eyes from damage while still allowing them to sense changes in light and dark.

The Purpose of Sleep for Cicadas

The exact purpose of cicada sleep is not fully understood, but it is thought to play a role in conserving energy. Cicadas are highly active at night, and they may need to rest during the day to conserve vital energy reserves.

Interestingly, cicadas have a unique way of conserving energy during their rest periods. They are able to recycle waste products in their bodies, such as uric acid, into a substance called “guanine.” This substance is then stored in their exoskeletons, which helps to regulate their body temperature and conserve energy during periods of rest.

How Cicadas Rest During the Day

During periods of rest, cicadas may lower their metabolic rate, enter a state of torpor, or simply decrease their activity. They may also move to cooler or darker locations to conserve energy.

Interestingly, cicadas have been observed to synchronize their rest periods. This means that large groups of cicadas will rest at the same time, which may help to protect them from predators. By resting together, cicadas are able to reduce their individual risk of being attacked or eaten.

In conclusion, while cicadas may seem like simple creatures, their sleep habits are actually quite complex. By conserving energy and synchronizing their rest periods, cicadas are able to survive and thrive in their natural habitats.

The Impact of Environmental Factors on Cicada Sleep

Environmental factors can play a significant role in cicada sleep patterns. Temperature, light, and humidity can all affect how and when cicadas rest.

Temperature and Sleep in Cicadas

As ectothermic animals, cicadas are highly sensitive to temperature. Extreme heat or cold can disrupt their natural sleep patterns, causing them to rest more or less than usual.

Research has shown that cicadas prefer to rest in temperatures between 22-27°C (71.6-80.6°F). In temperatures above or below this range, cicadas may experience disruptions in their sleep patterns. In extremely hot temperatures, cicadas may rest for longer periods of time to conserve energy, while in colder temperatures, they may become more active to generate heat and maintain their body temperature.

The Effect of Light on Cicada Sleep Patterns

Light exposure can also affect cicada sleep patterns. Increased exposure to light during the day can disrupt their natural rest periods, while decreased light exposure at night can signal the cicada to become more active.

Studies have shown that cicadas are most active during the day and prefer to rest at night. However, exposure to artificial light sources, such as streetlights or buildings, can disrupt this natural pattern. This can lead to cicadas resting during the day and becoming more active at night, which can be detrimental to their survival.

How Weather Conditions Influence Cicada Sleep

Humidity and other weather conditions can also play a role in cicada sleep patterns. High humidity can make it difficult for the cicada to regulate their body temperature, leading to increased periods of rest.

During periods of high humidity, cicadas may rest for longer periods of time to conserve energy and avoid dehydration. However, if the humidity remains high for an extended period of time, it can lead to fungal infections and other health issues for the cicada.

In addition to temperature, light, and humidity, other environmental factors can also impact cicada sleep patterns. These include noise pollution, air pollution, and changes in their natural habitat. As cicadas continue to face environmental challenges, it is important for researchers to understand how these factors impact their behavior and survival.


So, do cicadas sleep? Yes, they do, but their sleep patterns are quite different from those of humans. Cicadas rest during the day, exhibiting decreased activity and responsiveness to stimuli. While the exact purpose of cicada sleep is not fully understood, it is thought to play a role in conserving energy. Environmental factors, including temperature, light, and humidity, can all affect cicada sleep patterns, highlighting the fascinating world of these nocturnal insects.