Fjærtråden
Fjærtråden, a term derived from Norwegian, translates to "feather thread" or "plume fiber." It refers to the delicate, filamentous structures found in the downy part of a bird's feather. These threads are distinct from the stiff central shaft (rachis) and the broader vane of the feather. Instead, fjærtråden are soft, wispy filaments that barb off from the base of the feather's barbules, creating a fluffy, insulating layer.
The primary function of fjærtråden is thermoregulation. Their loose structure traps air, providing excellent insulation and
In some contexts, fjærtråden might also be used metaphorically to describe something extremely fine, light, or