Russell Lande is a theoretical population biologist who has applied rigorously quantitative analysis to questions of genetics, evolution and extinction. His studies of genetic diversity and changing population structures provide essential background to species conservation, in which he has taken a prominent advisory role.

The tools Russell developed to analyse phenotypic and quantitative genetic changes in natural populations are now standard in evolutionary biology. These tools address the multiplicity of both genetic and environmental variables that collectively impact on a species.

Russell developed and applied stochastic demographic theory to assess the risk of extinction in nonterritorial populations, and the survival of a territorial species if its habitat becomes increasingly fragmented. His work has influenced the International Union for the Conservation of Nature (IUCN) in its classifications of threatened species, taking into account not only current numbers but also likely times to extinction.