That Bird Blog – Bird Care and History for Pet Birds

The chipper little zebra finch, ever popular in the lab and home, has once again shed some light on topics important to those who study both birds and people.

Hearing and Correcting the Song

Researchers at Switzerland’s Zurich University have shown that certain cells in zebra finch brains become active when the bird makes a mistake in its song, or when a disruption is introduced into a recording of another’s song.  This offers the first proof that birds listen to their own songs, and compare what they hear to an “ideal” song that is stored somewhere in the brain.

Implications for People

Human language skills are thought to develop in a similar manner, but the functioning of the neurons involved is largely unknown.  The recent discoveries concerning finches may point the way towards a better understanding of speech development in people.

Song and Speech Timing

In related experiments, it was discovered that a specific area of the brain, the High Vocal Center, controls the timing of zebra finch singing.  Cooling this area of the brain slowed the song’s tempo, but did not affect the sequence of the notes (one is tempted to wonder why the birds kept singing while their brains were being chilled!).

Birdsong and human speech both require a complex series of timing adjustments if they are to be understood by others of their species.  The Zurich researchers are hopeful that their work will have implications for those studying human speech impediments.

The zebra finch is one of the world’s most important laboratory animals, and studies of it have led to a staggering array of important discoveries.  An interesting summary of its many contributions is posted at:

http://genome.wustl.edu/genome.cgi?GENOME=Taeniopygia%20guttata

The colorful little zebra finch’s popularity as a pet makes it easy to forget its long history as a valuable research animal – from genetics to pharmacology, this species’ contributions have been extraordinary. This month, studies of the zebra finch have once again yielded new insights that may have far reaching implications.

A Plastic Immune System Response
According to an article published in the September, 2008 issue of American Naturalist, immune response in these birds is not the rigid, pre-set system it was once believed to be. Rather, zebra finches somehow balance the “metabolic cost” of their response to disease against other drains on their metabolisms. Pathogens may not be met with an all-out response if other factors are draining the birds of energy or nutrition.

For example, males exhibit a lower immune response when molting into their colorful, adult plumage, a process which likely uses up a great deal of the birds’ resources. Females that are laying eggs, especially if food is not abundant, also limit the functioning of their immune systems. Interestingly, only birds that have a well functioning immune system seem able to scale back their response to disease threats; those with weaker baseline immune systems respond as strongly as possible in all situations.

Future Benefits for People
This work may help to reveal if our own immune systems function differently at various points in our lives, and may point the way to new ways of viewing human disease and infection.

On a related topic, an interesting article illustrating how some birds alter the amount of energy invested in finding a mate is posted at:
http://www.sciencedaily.com/releases/2005/02/050205075748.htm