In fighting cancer, look to what other animals do

IN 1977 RICHARD PETO, an epidemiologist at Oxford University, observed a contradiction. Cancer begins as a mutation in a single cell. Organisms with more cells should therefore have a higher risk of developing it. Elephants, which have 100 times as many cells as human beings do, should swarm with malignancies. Whales, with ten times more again, should be barnacled with tumours. In fact, the planet’s behemoths are blessed with extremely low rates of cancer. Titanic bodies and tumour resistance have evolved in tandem. The secret of suppressing cancer may therefore be hidden in the genes of giants.