Author offers a flock of fascinating details about feathers

  • By Sharon Wootton Herald Columnist
  • Thursday, March 7, 2013 9:52pm
  • Life

“The Fluffy and Downy Show” will appear this spring at your bird feeder. Young birds, which have recently fledged, will be hunkered down near (or in) the seed, still waiting for Mama to feed them. (She won’t).

They’ll be all fluffed up with natal down (feathers), making them appear larger than the adults.

“They look like little linebackers out there,” said Thor Hanson, a conservation biologist.

Feathers grow in different forms. A downy feather has a little nub of a quill and fluffy branch strands that act as insulation. The feathers are pushed out by more mature feathers.

Hanson, a San Juan Islands’ resident is author of “Feathers: The Evolution of a Natural Miracle” ($16), a fascinating look at the natural and cultural history of feathers, and the winner of the John Burroughs Medal for natural history authors.

Most birds molt at least once a year. Feathers wear out through hard work and because of pests and parasites that degrade feathers over time, Hanson said.

“The physical strain on feathers is the underlying reason, but they can also molt to repair damage in case of a feathered blooper, such as hitting a window.”

Another purpose is served by molting.

“It’s molting for display, to molt in a set of feathers specifically designed to attract a mate … to have wonderfully bright plumage … to signal one’s sexual maturity and vigor,” he said.

The avian molting process is universal, but there are often different strategies.

“The Virginia rail is dashing about in the grass, constantly rubbing its feathers in the vegetation, and has to molt several times a year,” Hanson said,

A large seabird like an albatross has a different approach.

“They can’t molt all their wing feathers in one season. They’re too bloody big and can’t grow fast enough for them to molt, fly and breed at the same time.

“It’s a highly energetic process. Anyone who keeps chickens finds it’s frustrating to go to the expense of feeding a flock of molting chickens and buying eggs at the store,” Hanson said.

Why don’t we see more feathers on the ground?

“When birds are molting, they are getting rid of older feathers that are breaking down. They disappear pretty quickly. That’s why they are so bloody rare in the fossil records of birds,” Hanson said.

It’s a marvelous time to be interested in feather evolution.

“A trove of feathered dinosaurs is being discovered. Suddenly there are dozens of feathered species. It’s surprising to see how long ago that feathers were fully developed. The oldest feathered fossil is 160 million years old and had modern-looking plumes at that stage of evolution,” he said.

Hanson is fascinated by some of evolution’s tweaks, including feathers to generate sound.

“The club-winged manakins’ feathers are specially adapted. A manakin ‘plays’ its feathers like a violin during courting (by beating its wings over its back),” Hanson said.

In addition to denser bones than other birds, it has some oddly shaped secondary feathers on its wings, some with barbs that are next to some with ridges. The combination generates a tone.

The structures of feathers are incredibly diverse. Some absorb water, others repel water; some are incredibly aerodynamic, others are not; some are for display, others are not.

There are wings that generate sound loud enough so that we can hear them fly by, such as a raven’s. Other feathers are built to minimize sound, as are an owl’s.

“As a consequence of microstructures on the surface of the wing, certain sounds are made. An owl has feathers with special adaptations, long barbs to disturb the airflow to silence flight. But you can hear every wing beat of a raven.”

The most amazing thing about feathers is their diversity, Hanson said.

“When you look at the adaptations, there are all kinds of incredible feathers designed for a single purpose. There’s almost nothing else that serve so many purposes as well,” he said.

Columnist Sharon Wootton can be reached at 360-468-3964 or www.songandword.com.

More in Life

Beer and cupcakes: Snohomish brewer, baker form unlikely duo

Pacific Northwest Cupcakes uses SnoTown’s brews to make beer-infused sweet treats.

The art and science of weathervanes

They told the direction of the wind and aided in forecasting the, well, weather.

Hundreds of ways to pamper your home and yourself

Find fancy fridges to sparkling jewelry under one roof at home and gift shows in Everett.

This is exactly how a cleaning expert organizes her space in 20 minutes

Try these realistic and attainable tricks to land yourself a cleaner home.

Snohomish brewer flavors beer with chilies from mom’s back yard

Beer of the Week: Smoked rye forms sturdy foundation for SnoTown’s well-balanced Loose Rooster.

Fall is just another blooming season

October can be a time of spectacular colors in your garden.

Woodward Canyon Winery continues to weave masterpieces

Owner Rick Small uses grapes from vines he used when he made wine in his back yard in the 1970s.

Music in the mountains: ‘It’s a weather-dependant hobby’

Anastasia Allison of the Musical Mountaineers reflects on making music at the summits.

Great Plant Pick: Physocarpus opulifolius ‘Diabolo,’ purple-leaf ninebark

Grow it with shrub roses and perennials, and it combines with with ornamental grasses.

Most Read