When not climbing in the Alps, looking for rare plants in the desert, or searching for endangered butterflies in some remote valley in the Pyrenees, I am an historical biogeographer and lecturer at Johns Hopkins University, specializing in the biogeography of zoonotic diseases and modeling the movement patterns of their animal hosts.

I am the director of the BIOMAP-LAB, where our present projects center on the transmission pathways of the 2014-2016 Ebola virus outbreak in West Africa, the medieval patterns of plague spread in Eurasia and Europe, and the movement of avian H5N1 influenza in wild bird & mammal populations.

Fascinated by the biogeography and population dynamics of Lepidoptera, I am also the founder of the LEP-LAB, where our field research is focused on mapping the distribution and movement patterns of rare butterflies in the Ariège and Pyrenees of France, and on tracing the collectors and locations of the specimens cataloged in the monumental Biologia Centrali-Americana.

The author or editor of more than one hundred articles and books, including the New York Times bestseller, MAP: Exploring the World, my latest article, To Save Lives: Lessons of a Pandemic Cartographer, was published in the Transactions of the Institute of British Geographers, in August 2024.

A Fellow of the Royal Geographical Society, I find pondering the mysteries of butterfly flight, wondering about the fate of Colias ponteni, and marveling at the complexity to be found in Darwin’s tangled bank, strangely comforting.