Why Do Snakes Have Forked Tongues? | Deep Look

To us, a snake’s forked tongue evokes danger and deceit. But the tongue’s two sensitive tips, called tines, actually help the snake smell in stereo. That’s bad news if you’re a mouse ... SUBSCRIBE to Deep Look! Please join our community on Patreon! DEEP LOOK is an ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small. --- It’s the most infamous tongue in the world. But for snakes, that flicking tongue is the way they experience the world around them. “In snakes, the tongue has been so reduced to this little skinny, highly protrusive organ,” says the University of Connecticut’s Kurt Schwenk, who studies the unique ways snakes and lizards use their tongues. Like us, snakes have nostrils to breathe in air and sense odor. But snakes have a whole second system to help them track down prey, find mates and avoid predators. In a single second-long flick, a snake might wave its tongue up and down as many as 15 times to collect odor molecules. As the snake retracts its tongue, it will often drag the forked tips on the ground. “Back inside the mouth, each of the tongue tips fits into a separate groove once it comes into the mouth,” says Schwenk. “Those two grooves go back separately to the opening of the vomeronasal organs.” The two vomeronasal organs, which act like a second odor-collecting system, allow the snake to pick up tiny concentrations of scents. By having two vomeronasal organs, one each? on the right and left side, the snake can smell in stereo. --- How do snakes move? Snakes don’t have limbs, so they use their long, flexible bodies to crawl on surfaces. Undulating waves of muscular contractions create forward momentum, and scales on their bellies help snakes get traction on the ground to push forward. --- Why do snakes shed their skin? As snakes grow, their skin doesn’t stretch, so they periodically shed it. The process of shedding, called ecdysis, also allows snakes to replace worn or damaged scales and get rid of parasites on the skin’s surface. --- Why do snakes hiss? Snakes hiss as a warning to predators and other threats. To make the hiss sound, a snake will force air through its glottis, an organ it uses to breathe. --- Find additional resources and a transcript on KQED Science: --- For more information: Kurt Schwenk at the University of Connecticut studies how snakes and lizards use their tongues to feed and sense the world around them. --- More Great Deep Look episodes: Look Inside a Rattlesnake’s Rattle | Deep Look These Lizards Have Been Playing Rock-Paper-Scissors for 15 Million Years | Deep Look Nature’s Mood Rings: How Chameleons Really Change Color | Deep Look --- Shoutout! 🏆Congratulations🏆 to these fans on our Deep Look Community Tab to correctly answer our GIF challenge! Palak Gupta RGAMeijer Siddarth Chris47368 --- Thank you to our Top Patreon Supporters ($10 per month)! Burt Humburg Karen Reynolds Daisuke Goto Companion Cube David Deshpande Chris B Emrick Tianxing Wang Wade Tregaskis Mark Jobes Blanca Vides Kevin Judge Laurel Przybylski Cindy McGill monoirre Roberta K Wright Supernovabetty Titania Juang Syniurge KW Carrie Mukaida Rory B. El Samuels Jessica Hiraoka Cristen Rasmussen Jellyman SueEllen McCann Kelly Hong Mehdi Laurel Przybylski Levi Cai TierZoo Nicolette Ray Jeremiah Sullivan Noreen Herrington Elizabeth Ann Ditz Louis O’Neill --- Follow Deep Look and KQED Science on social: @deeplookofficial Instagram: Twitter: --- About KQED KQED, an NPR and PBS member station in San Francisco, serves Northern California and beyond with a public-supported alternative to commercial TV, radio and web media. Funding for Deep Look is provided in part by PBS Digital Studios and the members of KQED.