A really big shark got gobbled up by another, massive shark in 1st known case of its kind Livescience.comFirst evidence of predation on an adult porbeagle equipped with a pop-off satellite archival tag in the Northwest Atlantic FrontiersLarge sharks may be hunting each other – and scientists know because of a swallowed tracking tag EurekAlertShark-on-Shark Attack ‘Unexpected’ Solution To Marine Murder Mystery NewsweekScientists find evidence that pregnant shark was eaten by a bigger shark NBC News