Cicadas live underground as nymphs for most of their lives, emerging only to mate and lay eggs in trees. They are found in temperate to tropical climates worldwide, with a notable presence in the United States, especially the eastern states. Explore the fascinating lifecycle of cicadas and how their habitat varies by species.
POINTS
- Cicadas have a rich evolutionary background, with over 3,000 species globally distributed and a presence on every continent except Antarctica, with the greatest diversity in tropical regions.
- The majority of a cicada’s life is spent underground as nymphs, feeding on sap from tree roots, with some species like periodical cicadas living as long as 13 to 17 years before emerging.
- Cicadas exhibit remarkable adaptability, living underground as nymphs, utilizing trees for sustenance and reproduction, and some species even thriving in arid desert environments.
- In the United States, cicadas are predominantly found in the eastern, central, and southern states, with significant broods, such as Brood X, emerging in 13-year or 17-year cycles.
- Female cicadas lay their eggs in the branches of preferred deciduous trees, which can cause temporary damage but rarely result in long-term harm to healthy trees, and the forest ecosystem typically recovers quickly post-emergence.
Where Do Cicadas Come From?
Cicadas are fascinating insects with a rich evolutionary background that spans millions of years. These creatures originated long before humans walked the earth, with fossil records dating back to the Paleozoic era. Over time, they have evolved and adapted to various climates and regions, resulting in a diverse array of species with a broad geographical spread.
Origins and Evolutionary Background
Cicadas belong to the order Hemiptera and are well-known for their unique life cycle and the loud, distinctive songs of the males. They have evolved over 200 million years, with their closest relatives being leafhoppers, aphids, and bedbugs. The evolutionary success of cicadas is partly due to their long life cycles and mass emergences, which overwhelm predators and ensure the survival of the species.
Global Distribution of Species
Globally, there are over 3,000 species of cicadas, with new species still being discovered. These insects are found on every continent except Antarctica. The greatest diversity of cicadas is seen in tropical regions, but they are also prevalent in temperate zones. Some species, like the well-known periodical cicadas, are exclusive to North America.
Where Are Cicadas Found?
Cicadas are found in a variety of environments, from lush forests to arid deserts. Their presence in a particular habitat is largely determined by the availability of suitable vegetation for the nymphs to feed on underground and for adults to lay their eggs.
Diverse Habitats
In temperate forests, cicadas thrive among deciduous trees, which provide ample food and egg-laying sites. Tropical regions support a greater diversity of cicadas due to the abundance of tree species and a warmer climate that can sustain larger populations. Surprisingly, some cicada species have adapted to arid environments, although these tend to have shorter life cycles due to the harsher conditions.
Where Do Cicadas Live in the US?
In the United States, cicadas are primarily found in the eastern, central, and southern states. Their distribution is closely tied to the emergence of significant broods, which are large groups of cicadas that emerge in sync after spending several years developing underground.
Significant Broods and Cyclical Emergence
The most famous cicadas in the US are the periodical cicadas, which belong to the genus Magicicada. They emerge in 13-year or 17-year cycles, creating spectacular natural phenomena. These broods are mapped and numbered, with each having a specific geographic range. For instance, Brood X is one of the largest and most widespread, emerging across several eastern and central states.
Do Cicadas Live Underground?
Yes, the majority of a cicada’s life is spent underground. This is a critical phase of their lifecycle, where they undergo development from nymph to adult.
Subterranean Phase
After hatching from eggs laid in tree branches, cicada nymphs drop to the ground and burrow into the soil. Here, they will spend the next several years, with some species, like periodical cicadas, living as long as 17 years underground. During this time, they feed on sap from tree roots and undergo several stages of growth, molting as they mature.
How Long Do Cicadas Live Above Ground?
Once they emerge from the ground, a cicada’s lifespan above ground is remarkably brief, typically lasting just a few weeks. This phase is dedicated to reproduction, with males singing to attract females and females laying eggs for the next generation.
Adult Behaviors and Ecological Impact
Adult cicadas spend their time mating, laying eggs, and feeding. They do not cause significant damage to mature trees, but their sheer numbers can have a notable impact on the environment. The nutrients they return to the soil when they die, and the aeration from their burrowing activities, can benefit the ecosystem.
What Trees Do Cicadas Like?
Cicadas have specific preferences when it comes to the trees they utilize for feeding and egg-laying. Understanding these preferences is crucial for predicting the impact of cicada emergences on forest health and tree populations.
Preferred Trees for Feeding and Egg-Laying
Cicadas are generally drawn to deciduous hardwood trees, where they can feed on the sap and lay their eggs in the branches. Common favorites include oak, maple, and ash trees. They tend to avoid coniferous trees since their needles do not provide the type of sustenance cicadas require.
Impact on Trees and Ecosystem
While cicadas do not typically harm mature trees, their egg-laying activities can damage young saplings and weaker trees. The females make slits in the branches to deposit their eggs, which can cause “flagging,” or the browning of tree limbs. However, this is often a temporary setback, and most trees recover fully.
Where Do Cicadas Lay Their Eggs?
The selection of the egg-laying site is a critical decision for the female cicada, as it determines the survival prospects of her offspring.
Egg-Laying Process and Tree Selection
Female cicadas make calculated choices when selecting the trees for egg deposition. They typically choose trees that have softer wood, which allows them to easily create the slits needed for their eggs. The health of these trees post-emergence can be affected, but most trees survive the process.
Implications for Forest Health and Regeneration
The egg-laying habits of cicadas can have mixed effects on forest health. While the damage to individual branches can be unsightly, it rarely results in long-term harm to healthy trees. In some cases, the pruning effect of cicada egg-laying can stimulate new growth. Forests typically recover quickly from cicada emergences, and the nutrient-rich decomposition of adult cicadas can enhance soil fertility, supporting the next generation of forest growth.
