The authors use ecological theory to understand the spread, establishment, and dominance of three introduced organisms in New Zealand after episodes of natural and artificial environmental disturbance create opportunities for them to thrive.

Harriet Ritvo’s article for the Living Lexicon for the Environmental Humanities section views the proliferation of introduced species as a symptom rather than a cause, and urges the identification of the real causes through a reconsideration of the morally loaded rhetoric within which biological migration and transplantation are often couched.

Through a case study of the “invasive alien species” (IAS) narrative in South Africa, Susanna Lidström, Simon West, Tania Katzschner, M. Isabel Pérez-Ramos, and Hedley Twidle suggest that IAS oversimplifies the webs of ecological, biological, economic, and cultural relations to a simple “good” versus “bad” battle between easily discernible “natural” and “nonnatural” identities.