Coevolution promotes the coexistence of Tasmanian devils and a fatal, transmissible cancer.

This article focuses on modeling the eco-evolutionary dynamics of Tasmanian devils (Sarcophilus harrisii) and devil facial tumor disease (DFTD), a fatal transmissible cancer that has caused severe population declines. Using an individual-based model parameterized with nearly two decades of ecological, epidemiological, and genomic data, the study examines coevolution in three trait pairs: tumor transmissibility and devil resistance to infection, tumor growth rate and devil resistance to tumor growth, and tumor virulence and devil tolerance. Results indicate a high probability of long-term devil persistence and devil–DFTD coexistence over 50 generations (100 years), with coevolution—particularly increased devil tolerance and reduced tumor virulence—promoting population recovery to about 60% of pre-disease levels. The findings highlight the importance of integrating multivariate host–pathogen coevolution in predicting outcomes of emerging infectious diseases and have implications for conservation strategies that consider evolutionary responses in both host and pathogen.