Abstract
To investigate the mechanism of brain protection of woodpecker, we built a finite element model of a whole woodpecker using computed topography scanning technique and geometry modeling. Dynamic analyses reveal: (i) 99.7% of the impact energy is converted into strain energy in the bulk of body and 0.3% is converted into strain energy in the head after three successive peckings, indicating the majority of the impact energy is stored in the bulk of body; (ii) the strain energy in brain is mainly converted into the dissipated energy, alleviating the mechanical injury to brain; (iii) the deformation and the effective energy dissipation of the beaks facilitate the decrease of the stress and impact energy transferred to the brain; (iv) the skull and dura mater not only provide the physical protection for the brain, but also diminish the strain energy in the brain by energy dissipation; (v) the binding of skull with the hyoid bone enhances the anti-shock ability of head. The whole body of the woodpecker gets involved in the energy conversion and forms an efficient anti-shock protection system for brain.
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May P R, Fuster J M, Haber J, et al. Woodpecker drilling behavior. An endorsement of the rotational theory of impact brain injury. Arch Neurol, 1979, 36: 370–373
Ono K, Kikuchi A, Nakamura M, et al. Human head tolerance to sagittal impact. Reliable estimation deduced from experimental head injury using subhuman primates and human cadaver skulls. In: Stapp Car Crash Conference (24th) Proceedings. Warrendale: SAE, 1980, 101–161
Gibson L J. Woodpecker pecking: How woodpeckers avoid brain injury. J Zool, 2006, 270: 462–465
Oda J, Sakamoto J, Sakano K. Mechanical evaluation of the skeletal structure and tissue of the woodpecker and its shock absorbing system. JSME Int J Ser A, 2006, 49: 390–396
Villard P, Cuisin J. How do woodpeckers extract grubs with their tongues? A study of the guadeloupe woodpecker (melanerpes herminieri) in the french west indies. Auk, 2004, 121: 509–514
Zhou P, Kong X Q, Wu C W, et al. The novel mechanical property of tongue of a woodpecker. J Bionic Eng, 2009, 6: 214–218
Seki Y, Schneider M S, Meyers M A. Structure and mechanical behavior of a toucan beak. Acta Mater, 2005, 53: 5281–5296
Wang L, Cheung J T, Pu F, et al. Why do woodpeckers resist head impact injury: A biomechanical investigation. Plos One, 2011, 6: e26490
Zhu Z D, Ma G J, Wu C W, et al. Numerical study of the impact response of woodpecker’s head. Aip Adv, 2012, 2: 042173
Agam G, Armato S G, Wu C H. Vessel tree reconstruction in thoracic CT scans with application to nodule detection. IEEE Trans Med Imag, 2005, 24: 486–499
Wan S Y, Ritman E L, Higgins W E. Multi-generational analysis and visualization of the vascular tree in 3D micro-CT images. Comput Biol Med, 2002, 32: 55–71
Rydberg J, Buckwalter K A, Caldemeyer K S, et al. Multisection CT: Scanning techniques and clinical applications. Radiographics, 2000, 20: 1787–1806
Wegst U G K, Ashby M F. The mechanical efficiency of natural materials. Philos Mag, 2004, 84: 2167–2181
Chen P Y, Lin A Y M, Lin Y S, et al. Structure and mechanical properties of selected biological materials. J Mech Behav Biomed Mater, 2008, 1: 208–226
Cheng S, Lau K T, Liu T, et al. Mechanical and thermal properties of chicken feather fiber/PLA green composites. Compos Part B Eng, 2009, 40: 650–654
Meyers M A, Chen P Y, Lin A Y M, et al. Biological materials: Structure and mechanical properties. Prog Mater Sci, 2008, 53: 1–206
Li B W, Zhao H P, Feng X Q, et al. Experimental study on the mechanical properties of the horn sheaths from cattle. J Exp Biol, 2010, 213: 479–486
Taylor Z, Miller K. Reassessment of brain elasticity for analysis of biomechanisms of hydrocephalus. J Biomech, 2004, 37: 1263–1269
Sack I, Beierbach B, Wuerfel J, et al. The impact of aging and gender on brain viscoelasticity. Neuroimage, 2009, 46: 652–657
Iwaniuk A N, Nelson J E. Can endocranial volume be used as an estimate of brain size in birds? Can J Zool-Rev Can Zool, 2002, 80: 16–23
Wygnanski-Jaffe T, Murphy C J, Smith C, et al. Protective ocular mechanisms in woodpeckers. Eye, 2007, 21: 83–89
Colly C. The jackhammer in your backyard. Reas Revel, 2009, 29: 33–36
Stark R D, Dodenhoff D J, Johnson E V. A quantitative analysis of woodpecker drumming. Condor, 1998, 100: 350–356
Yoon S H, Park S. A mechanical analysis of woodpecker drumming and its application to shock-absorbing systems. Bioinspir Biomim, 2011, 6: 016003
Harrison S M, Whitton R C, Kawcak C E, et al. Relationship between muscle forces, joint loading and utilization of elastic strain energy in equine locomotion. J Exp Biol, 2010, 213: 3998–4009
Alexander R M, Bennet-Clark H C. Storage of elastic strain energy in muscle and other tissues. Nature, 1977, 265: 114–117
Boyer K A, Nigg B M. Muscle activity in the leg is tuned in response to impact force characteristics. J Biomech, 2004, 37: 1583–1588
Yamamoto T, Minato T. Theory of energy dissipation in a viscoelastic body under time-dependent stress. Adv Space Res, 2007, 39: 472–476
Cooper T E, Trezek G J. Correlation of thermal properties of some human tissue with water content. Aerosp Med, 1971, 42: 24–27
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Zhu, Z., Zhang, W. & Wu, C. Energy conversion in woodpecker on successive peckings and its role on anti-shock protection of brain. Sci. China Technol. Sci. 57, 1269–1275 (2014). https://doi.org/10.1007/s11431-014-5582-5
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DOI: https://doi.org/10.1007/s11431-014-5582-5