As mentioned in research theme I, cites are best described as urban habitat mosaics, rather than as simple endpoints in rural to urban gradients. Importantly, chronic environmental stress does not vary in a smooth gradient within cities. Instead, it is very common for habitats with very low chronic environmental stress (such as forest patches and city parks) to be surrounded by habitats with very high levels of chronic environmental stress (such as paved streets and industrially polluted areas). This disjunct distribution of habitats with varying levels of chronic environmental stress imposes unique challenges on non-humans living in cities.  Consequently, understanding patterns of diversity across habitats with varying levels of chronic environmental stress in cities will both advance eco-evolutionary understanding and inform conservation planning.

We have sites in different US cities (right now, New York City, Philadelphia-Camden, Raleigh-Durham, and New Orleans). Within each urban habitat mosaic, we examine (primarily ground-dwelling) arthropod diversity in habitats with varying levels of urban stress. We are additionally starting to assess arthropod diversity across habitats with varying levels of pollution in the Philadelphia-Camden urban matrix. Finally, we are also examining the consequences of acute disturbances from extreme weather events and fires for arthropod communities and their ecosystem services.

We seek to understand the ecological drivers that underlie variation observed in the diversity and composition of arthropod communities. Therefore, our lab employs both observational and experimental approaches to these research projects.

Savage Lab Projects: Pollution and arthropod diversity & composition across the urban habitat mosaic of the Philadelphia-Camden urban matrix; Resilience of NYC’s arthropods to Hurricane Sandy across varying levels of urban stress; Ant diversity, seed dispersal, and soil turnover in burned and unburned patches in the NJ Pinelands.