Tim studies complexity in the environment and works at the interfaces of landscape, population, community and ecosystem ecology. A major theme of his work is the influence of spatial heterogeneity on ecological processes. He is also a software developer and expert in R, C++ and SQL. Dr. Keitt authored the “rgdal” package exposing functions from the Geospatial Data Abstraction Library to the R language. This package is the top downloaded R package and is the basis of a large collection of dependent spatial data analysis packages for the R system.