Accession Number : ADA318028

Title :   Functional Design of Dolphin Blubber.

Descriptive Note : Final rept. May 93-Sep 96,

Corporate Author : NORTH CAROLINA UNIV AT WILMINGTON DEPT OF BIOLOGY

Personal Author(s) : Pabst, D. A.

PDF Url : ADA318028

Report Date : SEP 1996

Pagination or Media Count : 6

Abstract : The dolphin and its environment is sculpted by blubber - a complex, structural biomaterial. I have investigated the functional design of blubber by (1) measuring its 3-D architecture and its physical connections to other locomotor tissues, and (2) testing its dynamic biaxial stress/strain behavior. Blubber can be biomechanically modeled as an adipose hydrostat: thorax blubber is designed to maximize body volume and tailstock blubber is designed to resist torsion and to store strain energy during swimming. Blubber is directly connected to the axial skeleton in the caudal tailstock, permitting force transmission and limiting shear deformation. Dynamic and pseudostatic mechanical tests have demonstrated that blubber is both a resilient tensile and compressive spring with an elastic modulus similar to that of high-quality biological and synthetic rubbers. Preliminary data demonstrate that blubber resists stress-relaxation. Blubber is morphologically and mechanically well-suited to (1) limit large scale shear deformation that might occur across the skin's thickness and (2) function as a biological spring. This study is the first to present data that support the hypothesis that blubber may function as a spring to decrease the metabolic cost of swimming in dolphins.

Descriptors :   *COMPOSITE MATERIALS, *BOUNDARY LAYER, *DOLPHINS(MAMMALS), TEST AND EVALUATION, SHEAR PROPERTIES, THICKNESS, VOLUME, MECHANICAL PROPERTIES, COMPUTER AIDED DESIGN, BIOLOGY, DEFORMATION, MODULUS OF ELASTICITY, METABOLISM, TRANSMITTANCE, LIMITATIONS, HYPOTHESES, SKIN(STRUCTURAL), TORSION, SPRINGS, SWIMMING, SKELETON, ADIPOSE TISSUE, HYDROSTATS, LOCOMOTION.

Subject Categories : Medicine and Medical Research
      Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE