question: Why do Woodpeckers not get brain damage from hammering their head against trees all the time?
comment: Simple answer is that their tongue wraps around their brain, offering cussioning. URL_0
passages: BULLET::::- Ornithology: Ivan R. Schwab, of the University of California, Davis, and Philip R.A. May of the University of California, Los Angeles, for exploring and explaining why woodpeckers don't get headaches.
  
  BULLET::::- Peace: Howard Stapleton of Merthyr Tydfil, Wales, for inventing an electromechanical teenager repellant – a device that makes annoying high-pitched noise designed to be audible to teenagers but not to adults; and for later using that same technology to make telephone ringtones that are audible to teenagers but probably not to their teachers.
   The spongy bones of the woodpecker's skull and the flexibility of its beak, both of which provide protection for the brain when drumming, have provided inspiration to engineers; a black box needs to survive intact when a plane falls from the sky, and modelling the black box with regard to a woodpecker's anatomy has increased the resistance of this device to damage sixty-fold. The design of protective helmets is another field being influenced by the study of woodpeckers.
   The leading cause of illness and death in both industrial and developing nations is head injury . Scientists have been inspired by woodpeckers to advance helmet technology after learning about their ability to decelerate at 1,000 times the force of gravity continuously for an average of 15 pecks. It is estimated that the woodpecker drums its beak approximately 12,000 times per day. It is assumed that the woodpeckers do not suffer any brain damage at these forces that immensely exceed the human capacity. A company called Riddell, a manufacturer of helmets for the United States Army and American football, is developing helmets to mitigate the stress on the front of the brain in a design similar to some birds. Another helmet called the Kranium Paper Helmet created by Anirudha Surabhi was inspired by woodpecker's ability to absorb high impacts with their network of trabeculae. Since the mass production of the complex trabecular network is difficult, Surabhi settled to use a common shape found in nature, a hexagonal structure. After testing 150 different materials he found cardboard to be the most successful. The Kranium Paper Helmet could absorb 3× more force while being 15× lighter than a typical polystyrene helmet.
   Doubt was also cast on some of the auditory evidence (ARU recordings of double-raps) for the presence of ivory-billed woodpeckers in Arkansas and Florida. One group of researchers stated:
  
  All ARU double raps suggesting the presence of an ivory-billed woodpecker should be reconsidered in light of the phenomenon of duck wingtip collisions, especially those recorded in the winter months, when duck flocks are common across flooded bottomlands of the southeastern United States.
  
  Section::::Status.:2004/2005 Arkansas reports.:Cornell search efforts 2005–09.
   Section::::Research.:Black box.
  
  Improvements to the impact strength of black boxes are being designed based on the head of a woodpecker. They consist of hard layers of steel and aluminum to mimic their beak and skull, an elastomeric component to uniformly disperse vibrations away from the skull like the hyoid bone , and a porous structure made of glass microspheres to dampen vibrations like trabecular bone. This structure survived a test up to 60,000 Gs.
  
  Section::::Research.:Trabecular metal material.
   Just like in humans, the distribution of trabeculae in bird species is uneven, depending on the loading conditions. The bird with the highest density of trabeculae is the kiwi, a flightless bird. There is also uneven distribution of trabeculae within the similar species such as the great spotted woodpecker or grey-headed woodpecker. After examining a microCT scan of the woodpecker's forehead, temporomandibulum, and occiput it was determined that there is significantly more trabeculae in the forehead and occiput. Besides the difference in distribution, the aspect ratio of the individual struts was higher in woodpeckers than in other birds of similar size such as the Eurasian Hoopoe or the lark. The woodpeckers’ trabeculae are more plate-like while the hawk and lark have rod-like structures networked through their bones. The decrease in strain on the woodpecker's brain has been attributed to the higher quantity of thicker plate-like struts packed more closely together than the hawk or hoopoe or the lark. Conversely, the thinner rod-like structures would lead to greater deformation. A destructive mechanical test with 12 samples show the woodpecker's trabeculae design has an average ultimate strength of 6.38MPa, compared to the lark's 0.55MPa.
   The professor proceeds to relate how he outsmarted and captured Woody. In a forest, he hears Woody pecking away at a tree. He gets up and catches Woody, who bops the professor with a mixture of Tabasco and chili powder. With a roar, the revived professor expels the mixture, which hits a tree and reduces it to ashes. The professor then employs various ways and means to capture Woody. He finally traps Woody in a cage, and we see both of them in the taxidermy shop, with Woody on the pedestal. The professor says, "Right." Woody's still alive and pecking away, this time at the professor.
   Section::::Status.:Louisiana 2006/2008.
   Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Eurasian wryneck, "Jynx torquilla" (*)
  
  BULLET::::- Lewis's woodpecker, "Melanerpes lewis"
  
  BULLET::::- Red-headed woodpecker, "Melanerpes erythrocephalus" (*)
  
  BULLET::::- Acorn woodpecker, "Melanerpes formicivorus"
  
  BULLET::::- Gila woodpecker, "Melanerpes uropygialis"
  
  BULLET::::- Williamson's sapsucker, "Sphyrapicus thyroideus"
  
  BULLET::::- Yellow-bellied sapsucker, "Sphyrapicus varius"
  
  BULLET::::- Red-naped sapsucker, "Sphyrapicus nuchalis"
  
  BULLET::::- Red-breasted sapsucker, "Sphyrapicus ruber"
   Prum, Robbins, Brett Benz, and I remain steadfast in our belief that the bird in the Luneau video is a normal pileated woodpecker. Others have independently come to the same conclusion, and publication of independent analyses may be forthcoming [...] For scientists to label sight reports and questionable photographs as 'proof' of such an extraordinary record is delving into 'faith-based' ornithology and doing a disservice to science."
   BULLET::::- Collared aracari, "Pteroglossus torquatus"
  
  BULLET::::- Yellow-eared toucanet, "Selenidera spectabilis"
  
  BULLET::::- Keel-billed toucan, "Ramphastos sulfuratus"
  
  BULLET::::- Yellow-throated toucan, "Ramphastos ambiguus" (Near-threatened)
  
  Section::::Woodpeckers.
  
  Order: PiciformesFamily: Picidae
  
  Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Olivaceous piculet, "Picumnus olivaceus"
  
  BULLET::::- Acorn woodpecker, "Melanerpes formicivorus"
  
  BULLET::::- Black-cheeked woodpecker, "Melanerpes pucherani"
  
  BULLET::::- Yucatan woodpecker, "Melanerpes pygmaeus"
   Section::::Behaviour.:Breeding.
   Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  Section::::Tyrant flycatchers.
  
  Order: PasseriformesFamily: Tyrannidae
   BULLET::::- Genus: "Campephilus" (11 species, 2 possibly recently extinct)
  
  BULLET::::- Genus: "Chrysocolaptes" – megapicine flamebacks (9 species)
  
  BULLET::::- Genus: "Reinwardtipicus" – orange-backed woodpecker
  
  BULLET::::- Genus: "Blythipicus" (2 species)
  
  BULLET::::- Genus: "Gecinulus" (2 species; placement in Megapicini tentative)
  
  Section::::Relationship with humans.
   Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Yellow-bellied sapsucker, "Sphyrapicus varius"
  
  Section::::Ovenbirds.
  
  Order: PasseriformesFamily: Furnariidae
   BULLET::::- Red-rumped tinkerbird, "Pogoniulus atroflavus"
  
  BULLET::::- Speckled tinkerbird, "Pogoniulus scolopaceus"
  
  BULLET::::- Yellow-billed barbet, "Trachyphonus purpuratus"
  
  BULLET::::- Yellow-rumped tinkerbird, "Pogoniulus bilineatus"
  
  BULLET::::- Yellow-spotted barbet, "Buccanodon duchaillui"
  
  BULLET::::- Yellow-throated tinkerbird, "Pogoniulus subsulphureus"
  
  Section::::Woodpeckers.
  
  Order: PiciformesFamily: Picidae
  
  Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Buff-spotted woodpecker, "Campethera nivosa"
  
  BULLET::::- Fire-bellied woodpecker, "Dendropicos pyrrhogaster"
   BULLET::::- Northern emerald-toucanet, "Aulacorhynchus prasinus"
  
  BULLET::::- Collared aracari, "Pteroglossus torquatus"
  
  BULLET::::- Keel-billed toucan, "Ramphastos sulfuratus"
  
  Section::::Woodpeckers.
  
  Order: PiciformesFamily: Picidae
  
  Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Acorn woodpecker, "Melanerpes formicivorus"
  
  BULLET::::- Black-cheeked woodpecker, "Melanerpes pucherani"
  
  BULLET::::- Yucatan woodpecker, "Melanerpes pygmaeus"
  
  BULLET::::- Golden-fronted woodpecker, "Melanerpes aurifrons"
  
  BULLET::::- Yellow-bellied sapsucker, "Sphyrapicus varius"
   A common question asked is why woodpeckers do not get headaches. The forces produced during beak pounding and drumming, at high-speed acceleration and decelerations, are thought to be offset by a number of factors within the bill and skull. Dense spongy cranial bones, a relatively small brain, low cerebral spinal fluid, the unequal upper and lower bills of the beak and its position in relation to the brain work together to provide shock absorbency to the brain. Beak trajectory during pounding and drilling is straight and this reduces the forces of shearing and rotation.
  
  Section::::Behavior.:Vocalization/communication.
   Claims that the bird in the Luneau video is a normal pileated woodpecker are based on misrepresentations of a pileated's underwing pattern, interpretation of video artifacts as plumage pattern, and inaccurate models of takeoff and flight behavior. These claims are contradicted by experimental data and fail to explain evidence in the Luneau video of white dorsal plumage, distinctive flight behavior, and a perched woodpecker with white upper parts."
  
  Other workers made claims disputing the validity of the Luneau video, including a website discussing the evidence by Colby College biologist Louis Bevier, who stated:
   Section::::Description.
   Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Lewis's woodpecker, "Melanerpes lewis" (VR)
  
  BULLET::::- Red-headed woodpecker, "Melanerpes erythrocephalus" (VR)
  
  BULLET::::- Red-bellied woodpecker, "Melanerpes carolinus" (R)
  
  BULLET::::- Yellow-bellied sapsucker, "Sphyrapicus varius"
  
  BULLET::::- American three-toed woodpecker, "Picoides dorsalis"
  
  BULLET::::- Black-backed woodpecker, "Picoides arcticus"
  
  BULLET::::- Downy woodpecker, "Dryobates pubescens"
  
  BULLET::::- Hairy woodpecker, "Dryobates villosus"
   Order: PiciformesFamily: Picidae
  
  Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Eurasian wryneck, "Jynx torquilla" (A)
  
  Section::::Shrikes.
  
  Order: PasseriformesFamily: Laniidae
   Section::::Description.
   Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
  BULLET::::- Olivaceous piculet, "Picumnus olivaceus"
  
  BULLET::::- Acorn woodpecker, "Melanerpes formicivorus"
  
  BULLET::::- Black-cheeked woodpecker, "Melanerpes pucherani"
  
  BULLET::::- Yucatan woodpecker, "Melanerpes pygmaeus"
  
  BULLET::::- Hoffmann's woodpecker, "Melanerpes hoffmannii"
  
  BULLET::::- Golden-fronted woodpecker, "Melanerpes aurifrons"
  
  BULLET::::- Yellow-bellied sapsucker, "Sphyrapicus varius"
  
  BULLET::::- Ladder-backed woodpecker, "Dryobates scalaris"
  
  BULLET::::- Hairy woodpecker, "Dryobates villosus"
   BULLET::::- Eastern screech-owl, "Megascops asio"
  
  BULLET::::- Great horned owl, "Bubo virginianus"
  
  BULLET::::- Barred owl, "Strix varia"
  
  Section::::Kingfishers.
  
  Order: CoraciiformesFamily: Alcedinidae
  
  Kingfishers are medium-sized birds with large heads, long pointed bills, short legs, and stubby tails.
  
  BULLET::::- Belted kingfisher, "Megaceryle alcyon"
  
  Section::::Woodpeckers.
  
  Order: PiciformesFamily: Picidae
  
  Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects. Some species have feet with two toes pointing forward and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
  
presuppositions: A woodpecker should get brain damage from hammering heads against trees.
corrections: A woodpecker's tongue wraps around it's brain which offers cushioning.
raw_presuppositions: A woodpecker should get brain damage from hammering heads against trees. A woodpecker should get brain damage from hammering heads against trees.
raw_corrections: A woodpecker's tongue wraps around it's brain which offers cushioning. A woodpecker's tongue wraps around its brain which offers cushioning.