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Using a Thermal Camera to Measure Heat Loss Through Bird Feather Coats
Published on: June 17, 2020
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How localized force spreads on elastic contour feathers.
Kinjal Bhar1, Brian Chang2,3, Emmanuel Virot4
1Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA.
Journal of the Royal Society, Interface
|November 21, 2019
Summary
Bird contour feathers spread impact forces, protecting the skin during dives. This study shows feather structure reduces impact pressure by up to three times, maintaining plumage integrity.
Area of Science:
- Biomechanics
- Zoology
- Materials Science
Background:
- Birds encounter significant localized forces during activities like diving and landing.
- Plumage integrity is crucial for avian survival and flight capabilities.
Purpose of the Study:
- To investigate the hypothesis that densely packed contour feathers spread localized impact forces.
- To understand how feather structure contributes to protecting the bird's body during high-impact events.
Main Methods:
- Micro computed tomography (micro-CT) scanning to analyze feather internal structure and determine Young's modulus.
- Modeling feathers as pre-curved, non-uniform elastic beams.
- Experimental testing with polycarbonate beams and development of a theoretical model for multiple overlapping feathers.
Main Results:
- Young's modulus of contour feathers from northern gannets was found to be of the order of 10^9 Pa.
- Experiments with elastic beams demonstrated force redistribution due to feather interaction.
- The theoretical model predicted up to a three-fold reduction in skin pressure without feathers.
Conclusions:
- Densely packed contour feathers effectively spread impact forces, mitigating localized pressure on the bird's skin.
- Feather structure and arrangement play a vital role in protecting birds from impact during dynamic movements.
- This protective mechanism is essential for maintaining plumage integrity and overall avian survival.
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