Cancer is an evolutionary inevitability of multicellularity that emerges when cooperative cellular networks collapse into competition for survival and replication. Despite decades of extensive research, progress in cancer treatment remains limited, partly because of the lack of an interdisciplinary perspective and an overreliance on murine models that fail to capture the full evolutionary spectrum and dynamics of oncogenesis. Comparative oncology is an interdisciplinary field that offers an eco-evolutionary framework to address these challenges by examining variation in cancer prevalence and defense mechanisms across the tree of life. In this review, we first explain why adopting an evolutionary lens is essential for understanding the challenge of cancer. Then, we review recent discoveries on genomic and life history determinants of cancer prevalence, remarkable species-specific cancer defense mechanisms, and methodological advances in analyzing cross-species cancer data. Insights from these findings can ultimately inform human cancer research and guide future directions in biodiversity conservation.
Fard et al. (2026) studied this question.