ZOO-ology column: Tongues work as tools
When is a tongue like a carpenter's rule, a spear, a plumbers snake or fly paper? How can a tongue help smell and what on earth is a fung-tongue?
Snakes and some lizards smell with the help of their tongues. Flicking tongues pick up microscopic particles and place them in openings on the roof of the mouth. These lead to sensitive Jacobson's organs that give information about possible danger or food. The spacing of the openings and forks in the tongues are a perfect match.
Deeply forked tongues indicate strong use of Jacobson's organs and shallower forks a lesser use.
Other creatures have variations of this ability.
Have you ever noticed a cat sniff something then hold its mouth slightly open as if savoring a scent?
A chameleon's tongue is almost twice its body length and zip-zaps at nearly 26 body lengths per second.
A woodpecker's tongue can be as long as the bird. It wraps around in the skull and can snake into tunnels in a tree. A barb at the end skewers grubs or bugs.
A nectar bat has tiny hairs on the end of its tongue that mop up pollen and nectar. The tongue attaches at the back of the mouth, but is so long, it's actually stored in the rib cage.
An anteater's two-foot long tongue is only a half inch wide and attached to the sternum (breastbone). Salivary glands ooze sticky saliva while the animal eats.
A giant anteater's tongue flicks at 150 times per minute, slurping up thousands of insects.
Cattle have flexible tongues that wrap around clusters of grass or plants.
A giraffe's blue/black tongue is 18 to 20 inches long, sticky, stretchy and great at helping keep its ears clean. It scrapes rough leaves across the teeth, making the giraffe's favorite acacia leaves more palatable.
What about the blue/black color? It may be a built-in sunscreen. Giraffes feed in very strong sunlight for hours at a time and the dark color is thought to protect against sunburn.
Grooming is another function of some tongues. Cats' tongues have rows of backward facing hooked spines.
Lion's tongues actually act as a rasp, scraping meat off the bones of their prey.
These types of tongues are also useful for removing parasites during grooming activity.
The alligator snapping turtle has a lure-like pink appendage on its tongue. It sits under water with mouth open wide. The turtle wiggles the lure, attracting fish and, violà, dinner is served.
The enormous 60-ton blue whale has a tongue that weighs 3 tons. A whale's huge tongue is used like a scoop while filtering food. It's estimated that 50 people could stand on the tongue of a blue whale.
Now, what about the fantastical fung-tongue? It's a tiny form of tuatara (lizard-like creature) that is strictly cave dwelling (troglobite).
Native to New Zealand, the tiny fung-tongue averages two inches and while it rates low on the metabolic scale, its tongue is terrific. A small growth of bioluminescent fungus lives on the tip and the glow acts as a lure to catch insects in the dark cave.
Fung-tongue, flicker or frog, there's always something of the fabulous to find.
The Texas Zoo is a perfect place to start.
Animal Tongues by Dawn Cusick
Judie Farnsworth is a longtime volunteer at the Texas Zoo specializing in educational programs.