Cancer Across Vertebrates

Cancer is a problem of multicellularity, making it a problem across all species. This pervasiveness has led to much research into the defense and the pathology of the disease. Previously, studies have been limited in sample size, taxonomic breadth, and comparative methods to explain and understand the data available. Here, we have access to life history and cancer risk data of 17,563 individuals for 327 species, spanning across three monophyletic clades: Amphibians, Sauropsids, and Mammals. Comparative biology’s approach to cross-species cancer prevalence is crucial to the identification of species that are uniquely resistant to cancer as well as stratifying risk across a phylogeny based on the life history framework. Using the life history framework, alongside a multitude of life history data, was able to find that neoplasia prevalence increases with adult weight and longevity, but decreases with gestation time. It was also discovered that malignancy prevalence decreases with gestation time. Gestation and adult weight are also both significant predictors of neoplasia and malignancy prevalence when controlling for the other. On an evolutionary scale, cancer risk appears to be best described by sudden shifts in cancer prevalence followed by stabilizing selection of that trait. The understanding of increases and decreases of cancer risk across species could create better insight on human’s own cancer risk, as well as disease prevention in humans.