The center of the woodpecker's muscle-wrapped hyoid is in the nostrils, in the bird's upper beak. It splits into a V between the eyes, and its two arms wrap completely around the woodpecker's skull, passing over the top of it and around the back before meeting up again at the base of the lower beak. When the muscles surrounding the hyoid contract, the tongue projects forward, through the length of the beak and out its end.
But when those muscles relax, the woodpecker's tongue retracts along the length of the hyoid. Yep — a woodpecker's tongue is so long that it needs to be coiled around the back of its owner's skull. Internal placement of a woodpecker's in this case, a Northern Flicker's tongue. Illustration by Denise Takahashi. The total length of a woodpecker tongue can be up to a third of the bird's total body length, although the exact proportions vary from species to species.
This includes both the part that sticks out past the end of the beak, and the part that stays anchored in the head. If our tongues were the same proportion, they would be around two feet long!
Occasionally those long tongues can even get woodpeckers into trouble. Scientists who catch woodpeckers for study sometimes have to carefully detangle the birds' tongues from their nets. In North America, the tongue-length champion is the Northern Flicker , with a tongue that can stick out two inches past the tip of this bird's bill. As for which species holds the world record — well, we're not sure anyone's ever measured the tongue length of all or so woodpecker species, and a definitive answer has yet to be given.
It depends! Although they all share the same basic anatomy, different woodpecker species have different tongues that are specialized for snagging various types of food. The Northern Flicker's extra-long tongue, for example, is sticky and relatively smooth, perfect for snaking deep into anthills to capture and retrieve ants. Pileated Woodpecker tongues, on the other hand, are relatively short, with barbed tips for extracting prey from bark crevices — maybe not what you'd expect from such a large woodpecker.
Sapsuckers , which mostly consume tree sap, may have the most interesting apparatus of all. Their brush-tipped tongues can lap up oozing sap by capillary action. Across a small enough diameter, the surface tension between water molecules and the attraction between these molecules and surrounding surfaces can actually be stronger than gravity.
Hummingbirds have a similar adaptation for drinking nectar out of flowers. Williamson's Sapsucker. Photo by Jim Chagares. Having its tongue wrapped around the back of its brain doesn't just give a woodpecker somewhere to store a long appendage; it also helps protect the bird's brain from injury during high-speed pecking. But the same can't be said for their freakishly long tongues.
This amazing photograph was shared with us by UK native Emma Shaw , and as you can imagine, it drew its share of scepticism. But let us assure you: the photo is no fake. The green woodpecker's tongue is quite the marvel — it's so long, in fact, that it has to coil behind the skull , over the eyes and into the right nostril in order to fit inside the bird's head:.
You can also see the internal action in this video, but be warned, it features a dissection and is not for the squeamish. Measuring in at ten centimetres 3. For a bit of perspective, if your tongue were that long, it would stretch out at around half a metre 1. As is the case with most peculiar body parts in the natural world, there's a resonable explanation here, and it's got to do with food.
During the spring and summer months, the green woodpecker's diet consists almost entirely of ants we've got the poop to prove it. While a beak is certainly a great tool for rooting around in topsoil, ant nests run deep — and it takes an avian "anteater" to get to them.
The woodpecker's strategy is simple: stick your face into soil or a crumbly fallen log, deploy your sticky mouth appendage, retract and enjoy the tasty spoils. A complex of cartilage and bone called the hyoid apparatus supports the tongues of all vertebrates. In birds, the small hyoid bones and cartilage extend to the tip of the tongue. Two horns of the hyoid, each consisting of narrow bones and cartilage, project backward and laterally from the base of the tongue.
In most birds, the horns of the hyoid terminate on either side of the trachea, but in woodpeckers they continue farther back. Muscles attached to the hyoid move the tongue; when the hyoid apparatus is moved forward, the tongue is extended. The greater the length of the hyoid horns, the farther the tongue can be extended.
The tongue can be several times longer than the bill. Woodpeckers came up with a creative solution. Rather than terminate below the skull, the hyoid horns continue over the back of the skull, just under the skin, and continue over the top of the skull. The two horns then join, extending forward as necessary — sometimes inserting into the right nostril. Downy, Hairy, Red-bellied, and Red-headed Woodpeckers all feed on insects and other organisms, as well as fruit.
Flickers, which likely eat more ants than any other North American bird, have a flattened tongue with few barbs and rely on sticky saliva to capture insects. The muscles of the tongue actually help insulate a woodpecker's brain from the shock of repeated pecks, decreasing its chances of developing serious brain injuries. The woodpecker's tongue basically acts as a helmet, holding everything in place and absorbing the force from each peck.
A combination of tongue bones and soft tissue, known as the hyoid apparatus , allow woodpeckers to do what they do best without suffering from constant concussions. It's not just the tongue that protects a woodpecker's brain — its entire skull is adapted for its rough lifestyle. The section of the skull that holds the brain is enlarged, holding the brain just above the area that receives the most impact from their pecking. The bones in the front of the skull are also crucial in reducing concussions, as they work together with muscles to absorb as much shock from hammering as possible.
A woodpecker's beak isn't just a tool, it can be a deadly weapon. One researcher found that out the hard way after he inadvertently caught a woodpecker double-homicide on camera while filming a pair of nesting morning doves. Two fledglings waiting for their mother to return to the nest were killed after a Gila woodpecker stopped by for a quick snack.
The woodpecker proceeded to ram its beak into the back of the doves' skulls, just enough to crack them open and slurp up their brains. Even the researcher who captured the video in the first place reported it was gruesome and difficult to watch. This was the first time that this behavior had ever been captured on camera, and it has changed many people's perceptions of harmless, cartoon-like woodpeckers.
Woodpeckers are named after their most notable activity: pecking wood. The technical term for pecking is actually " drumming ," and woodpeckers do this to tear into bark and extract food from inside. The type of food they go after varies depending on the species of woodpecker and the plants they are excavating, but insects and tree sap are two of their most common meals.
Some woodpeckers use their barbed tongues to capture tiny insects hidden deep within the bark. Woodpeckers are truly masters of their craft, striking at speeds up to seven meters per second. That's about 15 miles per hour of pure force, which is why they need so many layers of skull protection.
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