ABSTRACT
Mounting evidence points to loss of insect diversity over recent decades, and urbanization is implicated as a driver of insect declines. However, the effects of urban development on insect diversity are much more complex than simple reductions in species richness. In this chapter, we unravel this complexity by reviewing literature on the effects of key aspects of urbanization – habitat fragmentation, climate, pollution, land use, vegetation complexity, urban area age, and affluence – on insects that provide services and disservices within the urban landscape. We find that most studies focus on the flying (i.e. adult) life stages of particular insect clades, and that butterflies are overrepresented in the literature. Much past work focuses on the effects of habitat fragmentation and land conversion, while insect exposure to pollution and the effects of city aging and urban climates are poorly characterized. Finally, while the effects of neighborhood socioeconomic status on plant diversity are established, cascading effects on insect diversity have not been examined. Overall, we emphasize that more long-term studies within cities are needed to fully understand the effects of urbanization on insect diversity.
