Key points from article :
Scientists from the University of Reading, University College London, and Johns Hopkins University School of Medicine studied cancer prevalence in different species to investigate Peto’s paradox—the idea that large animals should get more cancer due to having more cells but don’t.
They analyzed a massive dataset of 16,049 necropsy records across 292 species, published their findings in the Proceedings of the National Academy of Sciences (PNAS), and concluded that larger species do show increased cancer rates, contradicting the paradox.
Their statistical approach controlled for body mass, length, and longevity, revealing a positive correlation between body size and cancer risk, particularly in mammals, amphibians, and reptiles.
However, critics argue that the study’s conclusions are overstated since the increase in cancer is not proportional to cell count, meaning large species still develop superior cancer defenses.
Notably, elephants have significantly lower cancer rates than expected, showing evolution’s role in counteracting size-related cancer risks. While the study challenges Peto’s paradox, researchers emphasize that understanding species with exceptional cancer resistance, such as naked mole rats and bats, could provide new insights into cancer prevention.
