Insects’ contributions to people: ecosystem services and functions provided by insects

With an estimated 10 million species, insects are central to nearly every terrestrial and freshwater ecosystem, driving ecological processes that support core ecosystem functions and the services derived from them. We review the contributions insects make to people, with a focus on supporting, regulating, and provisioning ecosystem services, rather than the ways these services impact human quality of life (e.g. livelihood creation, public health). We use the confidence framework adopted by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) to assess the amount and quality of scientific evidence, as well as the level of agreement within the scientific community. Insects are critical for habitat formation and maintenance through their roles as decomposers of plant and animal matter, removing dead biomass and cycling nutrients through ecosystems. As seed dispersers and pollinators, they structure plant communities, influence the genetic diversity of wild plants and crops, and are essential for food security. They play roles in decontaminating soils, purifying freshwater, regulating climate cycles, and transporting nutrients. In trophic webs, they regulate pest and disease vector populations, and serve as prey for insectivorous species that directly and indirectly support food security and livelihoods. Products derived from insects span from fabrics and dyes, to wound dressing, to water-repellant materials, and compounds used in vaccines. Declines in insects jeopardize ecosystem functions and human well-being in ways that far exceed economic accounting, eroding life-supporting services whose value is beyond measure.