Insects were largely recognised as pests that negatively impact people, especially in terms of agricultural destruction and as vectors of diseases. In recent years, however, insects are increasingly being valued for providing ecosystem services that are crucial for sustaining natural ecosystems. It was estimated that insects provide at least $57 billion of ecosystem services in the United States alone yearly (Losey & Vaughan, 2006)!
In 2016, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) estimated that insect-provided pollination services has a global economic value of $235-577 billion yearly (IPBES, 2016). About 15 to 30% of food consumed, especially fruits and vegetables, and more than 65% of all angiosperm species require insect pollinators (Axelrod, 1960; Kremen & Chaplin-Kramer, 2007). These pollinators include bees, butterflies, moths, wasps and flies, of which bees are considered to be the most important (Eggleton, 2020). Less intensive agricultural systems still rely largely on wild pollinators, while pollination in modern crop production systems is intensively managed. At least 90% of managed pollination services for food or seed production globally is performed by the managed populations of the honeybee, Apis mellifera (Kremen & Chaplin-Kramer, 2007).
Insects are also important nutrient recyclers and decomposers. In particular, soil insects, like dung beetles and termites, aid in soil transformation, soil bioturbation, plant decomposition and assist in nutrient cycling (Eggleton, 2020). Dung beetles support agricultural production by feeding and clearing livestock dung (see video below), which helps to move nutrients into the soil (Nichols, et al., 2008). Termites are considered as the most important “soil ecosystem engineers” in the tropics, They affect the distribution of water and nutrients in ecosystems, and in turn, the diversity of animals, plants and soil microbes (Jouquet et al., 2011).
Finally, insects can also help in controlling other pest species by feeding on them (Eggleton, 2020). Predatory ladybird beetles are well-known for their biological control of aphid infestations in agricultural crops (Bessin, 2019). In China, parasitoid Trichogramma wasps are widely used in biological control programmes to control more than 100 lepidoteran (butterfly/moth) pest species (Zang et al., 2021). Aquatic insects, like dragonfly nymphs and predaceous diving beetles, can also aid in controlling population of disease vectors, such as mosquitoes (Benelli et al., 2016).
