Science China Life Sciences

, Volume 54, Issue 11, pp 1036–1041 | Cite as

Comparative study of the mechanical properties, micro-structure, and composition of the cranial and beak bones of the great spotted woodpecker and the lark bird

  • LiZhen Wang
  • HongQuan Zhang
  • YuBo FanEmail author
Open Access
Research Papers


Woodpeckers are well able to resist head injury during repeated high speed impacts at 6–7 m s−1 with decelerations up to 1000 g. This study was designed to compare the mechanical properties, microstructures and compositions of cranial bone and beak bone of great spotted woodpecker (Dendrocopos major) and the Mongolian sky lark (Melanocorypha mongolica). Microstructures were observed using micro-computed tomography and scanning electron microscopy and their compositions were characterized by X-ray powder diffraction and Fourier-transform infrared spectroscopy. Under high stress, the cranial bone and the beak of the woodpecker exhibited distinctive mechanical features, which were associated with differences in micro-structure and composition, compared with those of the lark. Evolutionary optimization of bone micro-structure has enabled functional adaptation to the woodpecker’s specific lifestyle. Its characteristic micro-structure efficiently avoids head impact injury and may provide potential clues to the prevention of brain injury using bio-inspired designs of shock-absorbing materials.


woodpecker head mechanical property micro-structure composition 


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© The Author(s) 2011

This article is published under license to BioMed Central Ltd. Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  1. 1.Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina
  2. 2.School of Materials Science and EngineeringWuhan University of TechnologyWuhanChina

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