We humans go to great lengths to appear younger than we are. Sharks, it seems, do it naturally.

About a decade ago, studies began to hint that many sharks have longer lifespans than previously suspected. Now, a new analysis that pulled together data from more than 50 studies suggests a "widespread" underestimation of lifespans among many sharks, rays, and cartilaginous fish. (Explore the interactive: "Sizing Up Sharks, the Lords of the Sea.")

That's because newer methods of aging sharks—such as bomb carbon dating—are proving more accurate than the traditional method of counting the growth bands on vertebrae, says study author Alastair Harry, a fisheries scientist at Australia's James Cook University.

"Scientists were definitely already aware of [age underestimation], but perhaps did