sciencehabit writes: The surprisingly low cancer rates in elephants and other hefty, long-lived animals such as whales—known as Peto’s paradox after one of the scientists who first described it—have nettled scientists since the mid-1970s. So far, researchers have made little progress in solving the mystery or determining how other long-lived species beat cancer. Now, a new study shows that the animals harbor dozens of extra copies of one of the most powerful cancer-preventing genes, p53. These bonus genes might enable elephants to weed out potentially cancerous cells before they can grow into tumors. The researchers say they are now trying to determine whether they can make human cells more elephantlike, for example by inserting additional copies of the p53 gene or by identifying compounds that duplicate the effects of the extra copies.