30 July 2004

Something about feathers

Forrest M. Mims III

Birds don't take their feathers for granted.

In their spare time, birds carefully preen their wing feathers to make sure they are ready for efficient flight.

On cold nights, birds seem to double in size as they erect their body feathers to trap an insulating layer of air.

Scissor tail flycatchers swing their long tail feathers about to make instant flight maneuvers. This helps them catch insects that try to evade capture by suddenly trying to dive to the ground. It also helps males catch their mates.

Woodpeckers depend on their tough tail feathers to support them as they perch on tree trunks while hammering away.

Owls depend on specially designed feathers that have very soft edges. These feathers allow owls to glide toward their prey in almost total silence.

Standard feathers have much firmer edges that make distinct sounds as their owners fly and even as they glide.

Feathers don't last forever. They are periodically shed and replaced by new ones. Fortunately, this happens in a staggered fashion that allows birds to fly with a few missing wing and rail feathers.

Many male birds depend on their feathers to attract the attention of suitable mates or simply call them to task.

Recently a tom turkey provided us with a nice illustration of this while he was leading his harem of three hens around the field where I make sun and sky measurements.

Periodically, the tom would stop and raise his big fan of tail feathers. The hens would soon follow him to their next stop.

Some birds intentionally remove some of their soft breast feathers to line their nests. Wouldn't you want to rest on a bed of down and lichens if you were a baby bird?

Speaking of down, countless geese have given their all to provide the feathers for winter quilts, warm parkas and sleeping bags.

For some 1300 years people wrote with the quills of large wing feathers cut to form an ink delivery system capable of writing on parchment or paper.

Today's pen knife is named for the sharp little knives used to transform quills into pens. The word pen comes from penna, the Latin word for feather. All this is good for writers to know in case they run out of electricity and need a convenient way to write columns like this one.


Forrest M. Mims III and his science are featured online at http://www.forrestmims.org/.

This feature was originally published in Forrest Mims's weekly science column in the Seguin Gazette-Enterprise, Seguin, Texas. The column is written for a general audience.