WHY CICADAS MAKE NOISE

A Journey into the Symphony of Cicadas

Cicadas, those mysterious winged creatures with their piercing calls, have captivated humans for centuries. While their presence is often associated with the arrival of summer, their unique ability to produce a loud, distinctive sound remains a captivating spectacle. In this article, we'll delve into the fascinating world of cicadas, uncovering the secrets behind their remarkable noise-making prowess.

The Biological Machinery of Sound

At the heart of a cicada's ability to produce sound lies a specialized structure called the tymbal. This intricate organ, located on the insect's abdomen, comprises two vibrating membranes that are rapidly contracted and relaxed, generating a series of rapid clicks. The tymbal is connected to powerful muscles, which provide the necessary force for these rapid vibrations.

Resonating Chambers: Amplifying the Call

The tymbal's vibrations are amplified by a series of air sacs located within the cicada's body. These sacs act as resonators, emphasizing specific frequencies and enhancing the overall volume of the sound produced. The precise structure of these resonators varies among different cicada species, contributing to the diverse range of sounds they emit.

Communication and Mating Rituals

The primary purpose of cicadas' distinctive calls is to attract mates. Male cicadas use their songs to signal their presence and attract females. The pitch, rhythm, and complexity of these songs vary among species, allowing females to identify potential mates of their own kind. In some species, males also produce unique courtship songs, serenading their chosen partners in an attempt to win their favor.

Defense Mechanisms: Warning Predators

In addition to attracting mates, cicadas' calls also serve as a defense mechanism against predators. The loud, piercing sound can startle potential predators, giving cicadas a chance to escape. Some species of cicadas have even evolved the ability to produce ultrasonic sounds, which are inaudible to humans but can deter certain predators with sensitive hearing abilities.

Synchrony and Mass Emergences

Certain species of cicadas, known as periodical cicadas, exhibit a remarkable synchronized emergence pattern. These cicadas spend most of their lives underground, feeding on tree roots. After a predetermined number of years (typically 13 or 17), they emerge en masse, creating a cacophony of sound that fills the air. Scientists believe this synchronized emergence is an evolutionary strategy to overwhelm predators, as the sheer number of cicadas makes it difficult for predators to target and consume them all.

Beyond the Noise: The Significance of Cicadas

While cicadas are often perceived as a nuisance due to their loud calls, they play a crucial role in the ecosystem. Cicadas contribute to the decomposition of organic matter, aiding in nutrient cycling. They are also a food source for various animals, including birds, reptiles, and mammals. Furthermore, their calls attract predators that feed on cicadas, helping to control insect populations.

Conclusion: A Tapestry of Sound and Significance

Cicadas, with their unique ability to produce loud, distinctive sounds, are a captivating part of the natural world. Their calls serve as a symphony of communication, attracting mates and deterring predators. While their presence can be overwhelming at times, cicadas play a vital role in the ecosystem, contributing to nutrient cycling and supporting various animal populations. As we listen to the chorus of cicadas, let us appreciate the intricate biology and ecological significance behind their remarkable noise-making abilities.

Frequently Asked Questions:

1. Why do cicadas make noise?

Cicadas produce sound primarily to attract mates and deter predators. Their loud calls help them communicate with each other and establish territories.

2. How do cicadas produce sound?

Cicadas generate sound through a specialized structure called the tymbal, located on their abdomens. The tymbal comprises vibrating membranes that are rapidly contracted and relaxed, creating a series of clicks. These vibrations are amplified by air sacs within the cicada’s body, resulting in a loud, piercing sound.

3. Do all cicadas make noise?

Only male cicadas produce sound. Females lack the necessary structures for sound production.

4. Why do cicadas emerge periodically?

Certain species of cicadas, known as periodical cicadas, exhibit a synchronized emergence pattern. They spend most of their lives underground, feeding on tree roots, and emerge en masse after a predetermined number of years (typically 13 or 17) to mate. This synchronized emergence is believed to be an evolutionary strategy to overwhelm predators.

5. What is the ecological significance of cicadas?

Cicadas play a vital role in the ecosystem by contributing to the decomposition of organic matter and serving as a food source for various animals. Their calls also attract predators that feed on cicadas, helping to control insect populations.