Down feathers of geese insulate through special architecture.


"Feather keratin occurs in a 'b-sheet' configuration which differs from the a-helices that occur in mammalian keratins. . . We have measured the properties of individual down feathers from ducks, geese and penguins and found that their properties are similar to flight feathers and, indeed, the man-made polymers used in artificial insulation fibres. The message is that the architecture of down feathers is probably more important than material properties in determining their advantages over synthetic materials. . .Recently, we have begun to explore the toughness of feather keratin by using instrumented clippers and scissors. The fracture toughness of β-keratin has proved to be very high, around 10 kJ m-2." (Bonser 2007)

Comparison of keratin structure in down feathers and mammal hair. Artist: Emily Harrington. Copyright: All rights reserved. See gallery for details.

Journal article

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Mechanical properties of keratin

Journal article
Cameron, G. J.; Wess, T. J.; Bonser, R. H. C.

Canada GooseBranta canadensisSpecies