Coevolution of cooperative lifestyles and reduced cancer prevalence in mammals
Menée à partir de données portant sur plusieurs espèces animales et à l'aide d'un modèle mathématique, cette étude examine les raisons pour lesquelles certaines espèces sont plus sujettes que d'autres à développer des tumeurs malignes, met en évidence une relation entre les habitudes coopératives des espèces et la prévalence des cancers ou le risque de décès puis propose une explication mécaniste
Why cancer is so prevalent among mammals, despite the fact that some species evolved resistance mechanisms, remains an open question. We hypothesized that cancer prevalence and mortality risk might have been fine-tuned by evolution. Using public databases, we show that species with cooperative habits have lower cancer prevalence and mortality risk. By developing a mathematical model, we provide a mechanistic explanation: An oncogenic variant that elicits higher cancer mortality in older and less-reproductive individuals is detrimental to cooperative mammalian societies but can lead to a counterintuitive overcompensation in population size and fitness within competitive contexts. The phenomenon of a population increasing in response to a decrease in its per capita survival rate is called the hydra effect, a process never explored in the field of cancer before. Therefore, cancer can be considered as a selected mechanism of biological obsolescence in competitive species. While cooperative mammals evolve reducing cancer prevalence, oncogenes can be maintained by selection in competitive species.
Science Advances , article en libre accès, 2025