Male "ghost sharks"—eerie deep-sea fish known as chimaeras that are related to sharks and rays—have a strange rod jutting from their foreheads, studded with sharp, retractable teeth. New research ...

Scientists discovered true teeth growing on the head of the spotted ratfish, a distant shark relative. The toothed structure, called a tenaculum, helps males hold onto females during mating. Genetic ...

There’s no shame at all in having problems in the bedroom, but ‘sorry, my forehead teeth won’t get up,’ might be a new one. Male ratfish, also called ghost sharks, live in the depths of the ...