Geoff Boxshall is renowned for his research on crustaceans, and in particular copepods — tiny shrimp-like animals that are hugely abundant in the sea and freshwater habitats. Geoff studies the factors affecting copepod biodiversity on the largest scales. He is particularly interested in the evolutionary history and biology of parasitic copepods, especially sea lice. His work has illuminated copepod evolution and enriched our understanding of copepod ecology.

He discovered several new groups of crustaceans such as Tantulocarida — highly specialised parasites that, unlike other crustaceans, do not moult — and studied their life cycles. Appointed by the Natural History Museum in 1974 to carry out research, he is now a Merit Researcher there. He is currently Secretary of the Zoological Society of London and an Honorary Vice-President of the Marine Biological Association of the United Kingdom.

Geoff has published extensively, including several books — Copepod Evolution (1991), A Dictionary of Ecology, Evolution and Systematics (1998), and An Introduction to Copepod Diversity (2004). In 2004, he was awarded the Linnean Medal for zoology.