life cycle of a cicada

3 min read 14-03-2025

The cicada, with its distinctive buzzing song and striking appearance, is a fascinating insect with a truly unique life cycle. Unlike most insects, many cicada species have incredibly long life cycles, spending years underground before emerging en masse for a brief period of adult life. This article delves into the remarkable journey of a cicada, from its underground nymph stage to its short but impactful adulthood.

The Underground Years: The Nymph Stage

The life cycle begins with the tiny cicada nymph, hatching from eggs laid in tree branches by the adult cicada. These eggs hatch after several weeks, and the newly emerged nymphs drop to the ground.

Burrowing and Feeding

The nymphs immediately burrow into the soil, usually near tree roots. They feed on xylem, the fluid that carries water and nutrients throughout the tree. This subterranean existence can last for several years, even decades depending on the species. Some cicadas, like the periodical cicadas, are known for their extremely long nymph stages, spending 13 or 17 years underground.

Molting and Growth

During their underground life, cicada nymphs undergo several molts, shedding their exoskeletons as they grow larger. This process is crucial for their development and allows them to accommodate their increasing size. They remain hidden beneath the soil, feeding and growing until the time is right for their emergence.

Emergence and Transformation: From Nymph to Adult

After years underground, environmental cues trigger the nymphs to emerge. This typically occurs in late spring or early summer, when the soil reaches a specific temperature.

Crawling to the Surface

The nymphs emerge from the ground en masse, often creating quite a spectacle. They climb up trees, plants, or any vertical surface they can find.

The Final Molt: Metamorphosis

Once at a suitable location, the nymph undergoes its final molt. It sheds its exoskeleton, revealing the fully formed adult cicada. This transformation is a truly remarkable process, as the nymph's body completely restructures itself.

Adult Life: Singing, Mating, and Reproduction

The adult cicada's life is relatively short, lasting only a few weeks to a couple of months. Their primary goal during this period is reproduction.

The Male's Song: A Symphony of Summer

Male cicadas are known for their loud, distinctive songs. They produce these sounds by vibrating membranes called tymbals located on their abdomen. These songs serve to attract females for mating.

Mating and Egg Laying

Once a female is attracted, mating takes place. After mating, the female cicada uses her ovipositor (a specialized egg-laying organ) to lay her eggs in slits she cuts into tree branches. These eggs will eventually hatch, starting the cycle anew.

Death of the Adult

After laying eggs, the adult cicadas die, completing their life cycle. Their short adult life ensures the continuation of their species.

Types of Cicadas and Their Life Cycles

Not all cicadas share the same lengthy underground existence. There are annual cicadas, which emerge every year, and periodical cicadas, characterized by their 13- or 17-year life cycles. The reasons behind these long life cycles remain a subject of ongoing research. Some theories involve predator avoidance strategies. The mass emergence overwhelms predators, ensuring a significant number survive to reproduce.

The Significance of Cicadas in the Ecosystem

Cicadas play a vital role in their ecosystems. Their nymphs aerate the soil as they burrow. Adult cicadas are a food source for various animals, including birds, reptiles, and mammals. Their emergence can significantly impact plant life, but their overall effect on the environment is generally considered positive.

Conclusion: A Remarkable Insect

The life cycle of a cicada is a testament to nature's intricate and fascinating processes. From their lengthy underground existence to their brief but vibrant adult lives, these insects offer a compelling glimpse into the wonders of the natural world. Understanding their life cycle allows us to appreciate the complex interconnections within our ecosystems. Next time you hear that distinctive buzzing, take a moment to marvel at the amazing journey this creature has undertaken to reach its adult stage.