Why Woodpeckers Don't Get Headaches From Hammering

Ability To Hammer Into The Wood

The first talent is the ability to hammer into the wood and throw the chips away while creating a nest cavity or looking for tasty beetle grubs. Despite the woodpecker's head hitting the ground with at least 1,000 times the force of gravity (1,000 g), the bird doesn't seem to be hurt. A 100 g collision with a human, however, would surely result in death. So why don't woodpeckers have headaches or develop brain damage?

A Neck With Strong Muscles

Shock absorption by the bird is influenced by a variety of factors. One is a self-sharpening, chisel-like beak that moves into the wood as opposed to abruptly stopping. (See the preceding example.) Another is a neck with strong muscles. When the skull is smaller, the brain doesn't move around as much. The direction of the brain itself is also important since it spreads the force over a larger surface area.

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Researchers Studied Great Spotted Woodpeckers

Researchers from Beijing, China's Beihang University have recently used high-speed cameras, torque sensors, and scanning electronic microscopy to study Great Spotted Woodpeckers. In the bird's lower mandible and in areas of its skull that allow sliding (deformation), which decreases the force of pecks, they discovered minor changes in the bone structure. Additionally, they found that the boney structure of the woodpecker's lower beak was longer than that of its upper beak and that the tissue layer of the upper beak was longer than the layer of the lower beak. According to the researchers, this mismatch allows energy to be directed through the lower beak and away from the braincase.

Length Of A Woodpecker's Tongue

A tongue that is particularly long is the second adaption. One of the best-kept secrets in birdlore is the length of a woodpecker's tongue because it is frequently pushed into areas where we cannot see it. The greatest time to observe a woodpecker's tongue is during a flicker's anthill feeding trip.

As omnivores, woodpeckers consume a variety of foods, including nuts, juicy fruits, sap, insects, spiders, and other arthropods. Although a specialized tongue is not required to consume nuts and other types of fruit, it is a superb adaptation for reaching into narrow areas and grabbing delightful treats. This is particularly true when a woodpecker enters an insect gallery or an ant runs.

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Tongue Can Be Used As A Spear To Pierce And Then Drag Insects

The tongues of woodpeckers vary, but the majority are long, narrow, and have a variety of barbs that point backward near the tip. The tongue of a woodpecker can be used as a spear to pierce and then drag insects to the surface, but it is more likely to be used as a rake to extend into holes and then retract. Additionally, woodpeckers create a lot of sticky salivae that cover the tongue and aid in insect capture.

The tongues of all vertebrates are supported by a combination of bone and cartilage known as the hyoid apparatus. The tongue tip is reached via the tiny hyoid bones and cartilage in birds.

The Tongue Is Manipulated By Hyoid-Attached Muscles

The base of the tongue is followed by two hyoid horns that extend laterally and backward. Each horn is made up of a slender bone and cartilage. The hyoid's horns typically end on each side of the trachea in most birds, but in woodpeckers, they extend further back. The tongue is manipulated by hyoid-attached muscles; when the hyoid apparatus is pushed forward, the tongue extends. The tongue can be stretched farther the longer the hyoid horns are. In comparison to the bill, the tongue can be much longer.

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Storing A Long Tongue

Where to keep a lengthy tongue when not in use is a challenge. Woodpeckers devised a brilliant solution. The hyoid horns cross over the rear of the skull, just beneath the skin, and cross over the top of the head rather than ending below the skull. When necessary, the two horns stretch forward and connect, occasionally intruding into the right nostril.

The Downy, Hairy, Red-bellied, and Red-headed Woodpeckers all consume fruit as well as insects and other invertebrates. The tongues of the birds vary in length and have a number of barbs.

The Tongue Of Sapsuckers Is The Most Peculiar Of All Woodpeckers

Flickers have a flattened tongues with few barbs and rely on sticky saliva to grab insects; they probably consume more ants than any other bird in North America. The longest-tongued of our woodpecker species flickers frequently visit anthills where they move their tongues like snakes across the surface.

Unexpectedly, Pileated Woodpeckers have a tongue that is relatively short. Normally, they make extensive in-tree digs in search of invertebrates, particularly carpenter ants, which the larger birds appear to like. The tongue of sapsuckers is the most peculiar of all woodpeckers; it is short and ends in bristles that resemble brushes and are designed for sucking sap. Through the action of capillaries, the bristles absorb sap.

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Woodpeckers Benefit From Adaptations To Prevent Brain Damage

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Typically, sapsuckers create orderly rows of closely spaced, one-fourth-inch-diameter wells. In addition to sap, birds also eat insects, and they particularly enjoy those drawn to sap wells.

Woodpeckers benefit from adaptations to prevent brain damage from a life of hard knocks, and their large tongues allow them to catch hidden food morsels. The inventive adaptations are yet another illustration of the extraordinary lives of birds.