Why a surprising discovery, warming seas and the demise of the 'Meg' may spell trouble for more and more sharks

Some unexpected shark strandings and subsequent surprises following autopsies have ironically taken marine biologists millions of years back in time as they look to the future with concern. Adding chapters to an evolutionary tale involving the infamous megalodon shark (the "Meg"), they think their work suggests there are more warm-blooded sharks out there than previously believed, and—based on the Meg's demise—these species may be at great risk from warming seas.