Talk about efficiency. The University of Delaware’s Ocean Exploration, Remote Sensing, Biogeography Lab reeled in two sharks on one line last month while trying to recapture predators they’d tagged for research. To make the double catch even more remarkable, one shark, a 3-foot-long smooth dogfish shark, was brought in tucked inside the mouth of the larger sand tiger shark, like sharp-toothed marine matryoshka dolls. “This unlucky smooth dogfish couldn’t resist the menhaden used as bait and unfortunately fell victim to one of the top predators in the bay,” researchers wrote on the lab’s Facebook page. Now if they find another, smaller shark within that dogfish shark, it’ll really blow our minds.