Bird Integumentary system

• Integumentary system in birds: referring to their feathers

• During steep dives, peregrine falcons have been clocked at over 200 mph

The functions of the integumentary system in birds:

• Primary function: flight

• Secondary functions: waterproofing and insulations

Feathers

• Feather structure:

  • they are modified scales made of keratin

• Feather regions:

  • the shaft: made of two pieces

    • calamus: the cylindrical hollow base, also called the quill

    • rachis: squarish and solid, in the middle of the vain

  • the vain: has branches extending from the rachis called barbs

    • barbs have smaller branches called barbules

    • barbules have hooklets (or humuli) that allow them to interlock

      • velcro-like and increases strength

Feather Structure

• Leading vs. Trailing Edge

  • the trailing edge is thinner

• Top vs. Bottom of feather

  • more air below curve of feather than above

Types of Feathers

• contour feathers: the most abundant and obvious feathers, they are the flight feathers and they outline the body

• semiplunes: these feathers have an obvious rachis but no firm vane, they provide insulation and buoyancy

• down feathers: these feathers are small and have no rachis, provide insulation and waterproofing, and are often used to line nests

• bristles: these feathers have a long rachis, few barbs, and are found near the eyes, ears, nose, and mouth. The function like whiskers and are used for air filtration and to funnel food.

• filoplumes: these feathers have a long bare rachis with barbs at the end of them. They are used to enhance reproductive behavior and a good example would be peacock tail feathers.