Toucan and hornbill beaks: A comparative study

被引:63
作者
Seki, Yasuaki [1 ]
Bodde, Sara G. [1 ]
Meyers, Marc A. [1 ]
机构
[1] Univ Calif San Diego, Dept Mech & Aerosp Engn, Mat Sci & Engn Program, La Jolla, CA 92093 USA
基金
美国国家科学基金会;
关键词
Toucan beak; Hornbill beak; Sandwich structure; Brazier moment; BIOLOGICAL-MATERIALS; ELASTIC PROPERTIES; BONE; HARDNESS; TISSUE;
D O I
10.1016/j.actbio.2009.08.026
中图分类号
R318 [生物医学工程];
学科分类号
0831 ;
摘要
The structure and mechanical behavior of Toco Toucan (Ramphastos toco) and Wreathed Hornbill (Rhyticeros undulatus) beaks were compared. The beak of both species is a sandwich-structured composite, having an exterior, or rhamphotheca, consisting of multiple layers of keratin scales and a core composed of a fibrous network of bony closed-cell foam. The rhamphotheca is an arrangement of similar to 50 mu m diameter, overlapping, keratin tiles. The hornbill rhamphotheca exhibits a surface morphology on the ridged casque that is distinguishable from that observed on the bill proper. Intermediate filaments in the keratin matrix were observed by transmission electron microscopy. The Young's modulus measurements of toucan rhamphotheca indicate isotropy in longitudinal and transverse directions, whereas those of hornbill rhamphotheca may suggest anisotropy. The compressive response of beak foam is governed by brittle crushing behavior. The crushing strength of hornbill foam is six times higher than that of toucan foam. Micro- and nanoindentation hardness values were measured for rhamphotheca and foam trabeculae of toucan and hornbill specimens. The sandwich design of beaks was analyzed using the Karam-Gibson and Dawson-Gibson models. The presence of a cellular core increases the bending resistance (Brazier moment) by a factor of 3-6 while decreasing the compressive strength by only 50%. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
引用
收藏
页码:331 / 343
页数:13
相关论文
共 27 条
[1]  
Altman R.B., 1997, AVIAN MED SURG
[2]  
[Anonymous], 2006, VTK US GUID
[3]  
BONSER RCH, 1996, CONDOR, V95, P736
[4]  
BONSER RHC, 1995, J EXP BIOL, V198, P209
[5]   Structure and mechanical properties of selected biological materials [J].
Chen, P. -Y ;
Lin, A. Y. M. ;
Lin, Y-S. ;
Seki, Y. ;
Stokes, A. G. ;
Peyras, J. ;
Olevsky, E. A. ;
Meyers, M. A. ;
McKittrick, J. .
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS, 2008, 1 (03) :208-226
[6]   Structural biological materials: Overview of current research [J].
Chen, P. -Y. ;
Lin, A. Y. -M. ;
Stokes, A. G. ;
Seki, Y. ;
Bodde, S. G. ;
McKittrick, J. ;
Meyers, M. A. .
JOM, 2008, 60 (06) :23-32
[7]   The effect of tissue condition and applied load on Vickers hardness of human trabecular bone [J].
Dall'Ara, Enrico ;
Ohman, Caroline ;
Baleani, Massimiliano ;
Viceconti, Marco .
JOURNAL OF BIOMECHANICS, 2007, 40 (14) :3267-3270
[8]   Biomimetics: extending nature's design of thin-wall shells with cellular cores [J].
Dawson, M. A. ;
Gibson, L. J. .
DESIGN AND NATURE III: COMPARING DESIGN IN NATURE WITH SCIENCE AND ENGINEERING, 2006, 87 :145-+
[9]   Optimization of cylindrical shells with compliant cores [J].
Dawson, Matthew A. ;
Gibson, Lorna J. .
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES, 2007, 44 (3-4) :1145-1160
[10]   Fine structural dependence of ultraviolet reflections in the King Penguin beak horn [J].
Dresp, B ;
Langley, K .
ANATOMICAL RECORD PART A-DISCOVERIES IN MOLECULAR CELLULAR AND EVOLUTIONARY BIOLOGY, 2006, 288A (03) :213-222