![\"A](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/09\/Spotted-Ratfish-84db.gif\")
\n\t\tThis image is only slightly NSFW (Picture: Metro.co.uk)<\/p>\n
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\n\t\tThis image is only slightly NSFW (Picture: Metro.co.uk)<\/p>\n
There\u2019s no shame at all in having problems in the bedroom, but \u2018sorry, my forehead teeth won\u2019t get up,\u2019 might be a new one. <\/p>\n
Male ratfish, also called ghost sharks<\/a>, live in the depths of the north-eastern Pacific Ocean<\/a> and have bulbous green eyes, venomous spines and plates of teeth used to crunch the shells of clams and crabs. <\/p>\n They also have a fleshy rod inside a pocket above their eyes, a bit like the dorsal fin of an angler fish<\/a>, covered in spikes.<\/p>\n Now researchers have discovered that these are actually teeth, complete with mineralised tips.<\/p>\n These gnashes, however, aren\u2019t used for eating \u2013 this appendage, called a tenaculum,\u00a0is for gripping a female\u2019s pectoral fin during mating, new research has found. <\/p>\n Karly Cohen,\u00a0a researcher at the University of Washington\u2019s Friday Harbor Labs, who collaborated with the team, said scientists had never spotted teeth outside the mouth in this way before.<\/p>\n \t\t \t\t She said: This insane, absolutely spectacular feature flips the long-standing assumption in evolutionary biology that teeth are strictly oral structure.<\/p>\n \u2018The tenaculum is a developmental relic, not a bizarre one-off, and the first clear example of a toothed structure outside the jaw.\u2019<\/p>\n Gareth Fraser<\/a>, a professor of biology at the University of Florida<\/a> and senior author of the study, added<\/a>: \u2018If these strange chimaeras are sticking teeth on the front of their head, it makes you think about the dynamism of tooth development more generally.<\/p>\n \u2018If chimaeras can make a set of teeth outside the mouth, where else might we find teeth?\u2019<\/p>\n To clarify, Fraser doesn\u2019t mean ratfish are a chimaera, best known as\u00a0a fire-breathing monster with a lion\u2019s head, a goat\u2019s body and a serpent\u2019s tail.<\/p>\n Chimaera are cartilaginous fish like sharks, but lack many shark-like traits, like, well, sharp teeth or scales.<\/p>\n \t\t\t\tFollow Metro on WhatsApp to be the first to get all the latest news\t\t\t<\/p>\n \t\t Metro\u2019s on Whatsapp! Join our community<\/a> for breaking news and juicy stories.<\/p>\n \t\t But Fraser and his team wanted to know why ratfish actually have shark-like teeth, albeit ones on a club-like gripper used for sex.<\/p>\n So the researchers examined 40 ratfish specimens, with some over two and a half feet long, as well as fossils, according to the paper published in the Proceedings of the National Academy of Sciences<\/a>.<\/p>\n By using micro-CT scans, they watched as the tenaculum\u00a0grew over the ratfish\u2019s lifetime from a tiny nub to a long rod used to give love bites.<\/p>\n Molecular tests identified tooth-forming genes in the appendage, which are typically found in the mouths of sharks.<\/p>\n One of the ghost shark\u2019s ancient relatives, the Helodus simplex, which lived 315million years ago, also had a tenaculum\u00a0stretching from its snout to its upper jaw. <\/p>\n This suggests that tenaculum teeth formed because of\u00a0evolutionary tinkering or \u2018bricolage\u2019, said Michael Coates, a professor of biology at the University of Chicago<\/a>.<\/p>\n<\/p>\n \t\t \u2018We have a combination of experimental data with paleontological evidence to show how these fishes co-opted a preexisting program for manufacturing teeth to make a new device that is essential for reproduction,\u2019 he added.<\/p>\n For Fraser, how a gnarly, not-a-shark shark with a toothy appendage that hooks mates came to be isn\u2019t too surprising. It\u2019s the depths of the ocean, after all. <\/p>\n From fields of wispy crimson worms <\/a>to alien-like glowing snailfish that have never seen dayligh<\/a>t, all sorts of life thrives in this dark, crushing environment.<\/p>\n \u2018There are still plenty of surprises down in the ocean depths that we have yet to uncover,\u2019 Fraser said.<\/p>\n Get in touch with our news team by emailing us at webnews@metro.co.uk<\/a>.<\/strong><\/strong><\/strong><\/p>\n For more stories like this, <\/strong>check our news page<\/strong><\/a>.<\/p>\n Arrow Arrow Arrow![\"(Hydrolagus](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/09\/SEI_265228301-5082.jpg\")
\n\t\tRatfish are known to scientists as Hydrolagus colliei (Picture: Getty Images)<\/p>\n![\"Meet](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/09\/SEI_265228246-5f7b.jpg\")
\n\t\tThe frontal clasper sits inside a pocket when not in use (Picture: PNAS)<\/p>\n![\"Apps](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/09\/GettyImages-1632181964-e1700130460337.jpg\")
\n\t\tFollow us to receive the latest news updates from Metro (Picture: Getty Images)<\/p>\n![\"Meet](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/09\/SEI_265228303-2246.jpg\")
\n\t\tWe hope he\u2019s got a good dental plan at work (Picture: PNAS)<\/p>\n![\"Spotted](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/09\/SEI_265228297-3a01.jpg\")
\n\t\tThe rod is only present in male ghost sharks (Picture: Getty Images\/iStockphoto)<\/p>\n
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