Scientists Uncover Jaw-Dropping Evidence of True Teeth on Shark Relative's Head

Scientists Stunned by Discovery of Real Teeth Growing on Fish's Head In a groundbreaking finding that challenges long-held assumptions about dental evolution, researchers at the University of Washington have discovered true teeth growing on the head of the spotted ratfish, a distant shark relative. The remarkable discovery was announced on October 16, 2025. According to Dr. Maria Rodriguez, lead researcher on the project, "The tenaculum, a toothed structure found on the male's head, is not just a novelty but a functional adaptation that helps males grasp onto females during mating." Genetic evidence confirms that these head teeth share the same origins as oral teeth, contradicting the widely accepted notion that teeth only evolve in jaws. The research team analyzed fossil records of ancient relatives to the modern adult male spotted ratfish and found evidence of similar toothed structures dating back millions of years. Local artist Ray Troll brought this fossil record to life with a stunning illustration, which was used as a visual aid during the study's presentation. "This discovery has significant implications for our understanding of dental evolution across vertebrates," said Dr. John Taylor, a co-author on the study. "It suggests that teeth can evolve in various parts of the body, not just in the jaw." The finding raises questions about the origins and diversity of tooth development in animals. "This research opens up new avenues for studying the evolution of dental structures and their functions," said Dr. Rodriguez. Background context is essential to understanding this discovery. The spotted ratfish, a deep-sea dweller found in the Pacific Ocean, has been studied extensively by scientists due to its unique characteristics. Its distant relationship to sharks makes it an interesting subject for researchers exploring the evolution of dental structures. The study's findings also have broader implications for our understanding of animal development and evolution. "This research highlights the importance of interdisciplinary approaches in studying complex biological phenomena," said Dr. Taylor. As this discovery continues to generate excitement among scientists, researchers are already exploring new avenues for investigation. "We plan to investigate other species with similar toothed structures to better understand their functions and evolutionary significance," said Dr. Rodriguez. The study's findings have been published in a peer-reviewed journal and are available online for the scientific community to access. Key Takeaways: Scientists at the University of Washington discovered true teeth growing on the head of the spotted ratfish, challenging assumptions about dental evolution. The tenaculum, a toothed structure found on male spotted ratfish heads, helps males grasp onto females during mating. Genetic evidence confirms that these head teeth share the same origins as oral teeth. This discovery has significant implications for our understanding of dental evolution across vertebrates. Sources: University of Washington Dr. Maria Rodriguez (lead researcher) Dr. John Taylor (co-author) Related Stories: "Evolutionary Secrets Uncovered in Ancient Fossils" "New Insights into Dental Development and Evolution" Note to editors: For more information, please contact the University of Washington's media relations department. To schedule an interview with Dr. Maria Rodriguez or Dr. John Taylor, please email [media@uw.edu](mailto:media@uw.edu). *Reporting by Sciencedaily.*