The Role of Insects in the Ecosystem

   Did you know that insects comprise over 80% of all animal life and that entomologists estimate there may be as many as ten million undiscovered insect species? 

Out of the million species discovered, there are a vast number of services that are provided by insects and other invertebrates. Some commonly known services are acting as both prey and predator for wildlife species throughout the world; some species such as birds depend on insects as their main food source, and insects keep other insect populations in control and feed on plants to prevent overgrowth. 

There are many lesser-known roles that insects play in the natural world, however. Some of these include providing nourishment for the soil, and pollinators, aiding in the decomposition process, as well as providing pest control, which may seem contradictory. Without insects, this world would undoubtedly not be able to function with all of the animal and plant life it currently has.

Assorted insect species provided by University of Nebraska-Lincoln

     

Decomposers

     Insects are key decomposers when it comes to the natural world. Without decomposition, dead plant and animal matter would simply remain on the forest floor and take up room for new life to grow. 
As well as fungi, insects are amazing at breaking down matter to convert it into energy. A popular insect known for decomposing is the carrion and dung beetle. 

In the article "The Role of Insects in Ecosystems", carrion beetles are discussed as being attracted to the corpse of a dead animal, where they not only feed on the decomposing flesh but lay their eggs in it. As the eggs hatch, the larvae can feed on the animal as well and convert what was then known as a dead deer into simpler organic compounds. 

As for dung beetles, "These beetles consume feces, aiding in breaking down complex organic materials in dung, which often contains undigested plant material" (Verma et. al, 2023). 

Termites are another good example of decomposers, and they break down dead trees. Interestingly, before decomposers existed, dead trees would lay on the ground, eventually being buried because there was nothing that would feed on them. 

Dung beetle rolling feces (Ryan Plakonouris, 2019).

Nourishing the soil

       Additionally, insects are vital for nourishing the soil and promoting plant growth. Even though soil accounts for only 10% of the Earth's surface, it provides a home to many species of plants and animals alike. Without the soil, we would not have agriculture, forests, or any of the wildlife that lives within such forests. Although worms are not insects, they are often prized as one of the most important species to maintain soil. While this is true, many fail to realize that insects are also pioneers of the soil. 

    As mentioned by Verma, "Ants, with their intricate underground colonies, are another group of master soil engineers. Their subterranean chambers and tunnels can stretch extensively, significantly impacting soil structure" (Verma et. al, 2023). As the ants transport materials up and down their tunnels, they mix the soil, becoming natural tillers. Just as humans till to aerate their soil for their crops, ants unknowingly feed the soil oxygen and allow nutrients to better flow throughout it. Contrary to worms, who are native to Europe (even though they have now found themselves inhabitants of every continent), ants can be found almost everywhere on the planet as a native and beneficial species. 

Termites, as mentioned above, are also key for the soil. "But beyond their role as decomposers, their nesting and foraging activities, similar to ants, lead to soil turnover. They transport soil particles, mix them with organic matter, and in doing so, influence both the soil's physical structure and its chemistry" (Verma et. al, 2023). Termites play a similar role as ants, and they are natural soil mixers as they bring deeper material up into their mounds. 

Fire ant colony casting (Anthill Art)

     Predator and Prey

     The more well-known aspect insects are known for is their role in the food chain. There is a wide variety of animals that depend on insects for food, ranging from fish and reptiles to mammals and birds. Without an abundant population of insects, these species may starve or resort to finding other food sources that could disrupt the food chain. According to Jennifer D'Agostino, there are about 400 identified species of insectivore mammals, which include moles, shrews, hedgehogs, and anteaters, and these are just mammals. 

Many species of birds and reptiles primarily feed on insects and rely on a diverse population of beetles, ants, and flying insects to maintain a healthy diet. Also, many cultures and populations enjoy eating insects because of their high nutritional value and availability. "Humans have harvested the eggs, larvae, pupae, and adults of certain insect species from forests or other suitable habitats to eat for thousands of years" (Center for Invasive Species Research). In more tropical areas where larger bugs can be found, many people like to enjoy the taste and texture of insects as well as get a full meal. 

Cricket dish (Getty)

References:

    Entomophagy (Eating Insects) | Center for Invasive Species Research. https://cisr.ucr.edu/entomophagy-eating-insects. Accessed 11 Apr. 2024.

    Verma , R. C., Waseem , M. A., Sharma , N., Bharathi , K., Singh , S., Anto Rashwin A., Pandey , S. K., & Singh , B. V. (2023). The Role of Insects in Ecosystems, an in-depth Review of Entomological Research. International Journal of Environment and Climate Change, 13(10), 4340–4348. https://doi.org/10.9734/ijecc/2023/v13i103110

    Insectivora - an Overview | ScienceDirect Topics. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/insectivora. Accessed 11 Apr. 2024.

    Insect Diversity | Science Literacy and Outreach | Nebraska. https://entomology.unl.edu/scilit/insect-diversity#:~:text=There%20are%20more%20than%201%2C000%2C000,10%20million%20undiscovered%20insect%20species. Accessed 11 Apr. 2024.