 This study examined the genetic makeup of four rodents and six bats to determine if there was any correlation between their lifespans and cancer resistance. The results showed that the naked mole rat, which is known for its longevity, had significantly fewer copies of lines and signs than other rodents, suggesting that these types of transposable elements may be responsible for the increased cancer risk seen in shorter-lived animals. Additionally, the long-lived bats also had fewer copies of these elements, indicating that they too may be resistant to cancer due to their reduced copy numbers. This article was authored by Marco Ricchi, Valentina Piona, Olessio Boettini, and others.