This Downy Woodpecker 's tongue, for example, is three times as long as its bill. Woodpeckers have other amazing adaptations as well. They have a third eyelid, to protect their eyes when they are hammering away at a tree. And why don't they get headaches? Well, the third eyelid helps it acts like a seat belt and they've developed a large brain case, which prevents them from getting a concussion when they eat.
They've also developed one of nature's best shock absorbers — a muscle and bone structure at the base of their bill to cushion the impact of their feeding habits. Their tail also can act as a kickstand to prop them up, and they have two toes in the front and two in the back to give them a better grip most birds have three in the front and one in the back.
While the Downy Woodpecker is the most common woodpecker found in San Francisco, twelve species of woodpecker have been seen in the City. The most unusual woodpecker that I've seen was this hybrid woodpecker that I found at Lake Merced in January. At first glance, it reminded me of a Red-Breasted Sapsucker, a common summer resident in the humid forests of the Pacific Northwest, which is usually present in very small numbers in the winter in San Francisco.
But Red-Breasted Sapsuckers pretty much always have a completely red head. A number of bird species can hybridize with other species ducks in particular are known for this , which makes bird identification even more challenging. Sapsuckers drill rows of "sap wells" in the bark of trees, and then come back to drink the sap oozing from the tree.
Surprisingly, this doesn't seem to hurt the tree, and there are a number of places in San Francisco including in the San Francisco Botanical Garden in Golden Gate Park where you can see trees with thousands of holes drilled by our wintering sapsuckers.
There are a number of suggestions as to how woodpeckers resist the high impacts associated with their characteristic rapid pecking, but Wang and colleagues wanted to find out the extent to which all of these factors really play a role. To this end they analysed the movements and detailed anatomical features of great spotted woodpeckers Dendrocopos major , which could hold the key to their unique shock absorption system.
First, the team used high-speed video cameras to record the 3D movements of woodpeckers pecking at a sensor that recorded their pecking force.
What they observed were pecking speeds of over 7ms —1 and high decelerations on impact. Next, they used micro-CT scanning and microscopy to examine the bone and structures in the skull, and mechanically tested specimens of bone to obtain the exact mechanical properties of the tissue. They then modified various anatomical features, such as beak length, to examine the effects these had on how the force is transferred at impact. Finally, from the 3D model, the researchers found that the outer tissue layer of the upper beak is longer than that on the bottom but, conversely, the bone structure is longer on the bottom than on the top.
They think that these unequal lengths allow impact to be distributed away from the brain, via the lower beak. Although some of these adaptations are only useful if you are a woodpecker, scientists are keen to develop new woodpecker-inspired safety devices to keep us safe from impacts. Knowledge of the material properties and distribution of the shock-absorbing spongy bone can be incorporated into the design of new safety helmets.
It could well be that nature has revealed a potentially life-saving mechanism to prevent head impact injury. Read more about our commitment to Open Access. Glenn Tattersall talks about his experiences using a thermal imaging camera in South Africa, the Galapagos Islands, Scotland and Brazil.
It's a tough one to answer, says Walter Koenig , an ornithologist at Cornell University, via email. There are more than species of woodpeckers worldwide , and they peck wood for a variety of reasons: to excavate nest cavities, dig for insects or sap, or create holes to store food.
When selecting wood, the birds usually target trees weakened by fungal decay, which are easier to crack, Jerome Jackson , a behavioral ecologist at Florida Gulf Coast University, says via email. Some woodpeckers practice drumming watch video —a superfast pecking that attracts mates and defends territory—on a resonant surface, like a hollow tree. That allows for a louder noise while avoiding punishing impact. Acorn woodpeckers of North and Central America have another strategy: They carve out individual holes into trees, each just big enough to "squeeze in a single acorn"—storage for leaner times, Jackson says.
In a recent incident in California, acorn woodpeckers stashed pounds of acorns into a wireless antenna, disrupting communication in nearby towns. Watch the incredible video. For one, woodpeckers have tiny brains—just 0. The bigger the brain, the higher the mass and thus the higher the risk of brain injury, says Lorna Gibson , a professor of materials science and engineering at MIT who has studied woodpecker brains. Another factor that protects woodpecker noggins is the limited time the tree and their bill are in contact, she says.
It's brief—just one-half to one millisecond. By comparison, a typical human head injury happens between about three and 15 milliseconds. He writes mainly about emerging tech, physics, climate, and space. In his spare time, Tibi likes to make weird music on his computer and groom felines. Home Environment Animals. What's this bird made of? March 23, Reading Time: 3 mins read.
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