Adult zebra finches must undergo surgery to allow scientists to attach electrodes to multiple muscles. However, while these muscles are understood to directly control individual aspects of song production—for instance, the pitch of the sound produced—they also need to work together. The team found that measuring the activity of the syringealis ventralis alone could reliably capture the dynamics of birdsong ballads almost as accurately as the old technique of measuring multiple muscles.
In some cases, looking at the biomechanics can give you insights that are not so clear in the nervous system. Bush was eager to study the patterns of how muscles actually fired in slumber. Bush and his colleagues discovered that when the muscles are coaxed into activity, they behave in an all-or-nothing fashion. Even synthetic versions of these songs, remixed in the lab, could sometimes elicit vocal organ responses.
Often, the muscles were still—but when they were goaded into flexing, they would carry out the complete firing sequence of a vocalization. The scientists say this knowledge opens up new ways to study how musical musculature is spurred into action. Under observation: Manfred Gahr and Andries ter Maat placed the desk directly in front of the aviary.
In the corner of another room stands an aviary measuring two square meters in area and two meters high. Two plastic trees stand in the middle of the wood-chip strewn floor, and the cage is fitted with perches. The aviary is shielded by two sound-absorbing walls that also provide visual cover.
Two stainless steel antennae protrude into the aviary space. Two short, thin metal pins, partly covered by the feathers, protrude from the heads of some of the finches.
Such an electrode is familiar to anyone who makes electrophysiological recordings of animals, but the one used here is different. The pin is usually connected to a cable that transmits the neuronal signals emitted by individual or entire groups of neurons from the brain to a computer.
The fitting of the recording electrode is comparable to the fitting of a dental implant. But cables would not be very useful in an environment like this one, with its perches and artificial trees. The introduction of a second cabled-up animal to the mix would inevitably result in a jumble of cables.
Thus, instead of a cable, the researchers attach to the metal pins a radio transmitter weighing just one gram. This transmits the neuronal activity data to the stainless steel antennae, from which they are forwarded to the computer via the receiver. However, in view of the volumes of data produced by the recorded brain area, the mobile memory would quickly become full. The sampling rate is 20 kilohertz. This produces 22 kilobytes of data per second, which is just under 80 megabytes per hour and megabytes over the course of a ten-hour day.
Typically, data from up to eight animals is recorded simultaneously, which quickly results in several gigabytes of data every day.
The birds live a relatively undisturbed life here in a seminatural habitat: two plastic trees stand in the middle of the wood-chip strewn floor and the cage is fitted with perches. For this reason it is important that the transmitters do not restrict the animals in their movement. The transmission of the data by telemetry is not the problem either. As with all mobile devices, whether laptops, cell phones or digital cameras, the technical limits are dictated by battery size.
In the case of the bird transmitter, the researchers availed themselves of the smallest commercially available energy storage device they were able to find: a hearing-aid battery. The battery provides enough power for five days of constant operation, which is sufficient to produce initial results.
But such telemetric devices cannot simply be purchased at the local electronics store. The transmitter was, in fact, developed by the scientists themselves. He had already tinkered with just such a system in the s when he worked as the head of a junior research group at the old MPI for Behavioral Psychology in Seewiesen.
Today, he affords himself the luxury of the services of two electronics engineers who focus exclusively on this task. They regularly trawl the market for the latest developments. And their efforts pay off: they will soon complete the development from the analog to the digital age in mobile recording — and thus attain a crucial advantage: Analog technology allows the scientists to record only one location per animal, while the digital equivalent will enable the simultaneous recording of neurons in several locations of the avian brain.
Nevertheless, the behavioral physiologists are very pleased with what they have already achieved without the digital technology. Marjorie R. Leek — marjorie. Birdsong has long served as a model for vocal development and communication.
Zebra finches are a particularly interesting model because they sing just one song their entire lives, and they sing this song with little variation from rendition to rendition. Male zebra finches sing to other males to defend their territories and to females for mating displays. Thus, perception of song is important for species survival.
Songs consists of bursts of sounds syllables , separated by silence intervals Figure 2. A motif is a specific ordering of syllables. Motifs range from 3 to 8 syllables long, and each syllable in the motif is unique. Zebra finch songs consist of several introductory notes, followed by a few renditions of the motif, sung in a very repetitive manner. If we take a closer look at a single song motif, we can see that each individual syllable is acoustically complex.
Each syllable contains an amplitude envelope loudness cues spectral structure pitch, timbre, or frequency cues and temporal fine structure millisecond phase cues , which result in a set of syllables all of which are acoustically distinct.
Are all of these cues equally important for song perception? Previous work has shown that zebra finches are quite good at discriminating changes to their song motifs, specifically temporal reversals of single syllables i.
Below is an example of this type of change Figure 2. Finches: On extremely cold, snowy nights, American Goldfinches have been known to burrow into the snow to create a sleeping cavity. More often, they spend winter nights roosting with other goldfinches in coniferous trees. Is a house finch a sparrow? House Finches have large, thick beaks of a grayish color.
House Sparrows have a much more conical bill that is smaller than finches', and the bill is black or yellow, depending on the bird's gender and breeding stage. What does a finch symbolize? The bird is a sparkly symbol of high energy and brighter days on the horizon. Generally, the symbolism of the finch is an indication of liveliness, exuberance, and enthusiasm in your life. Finch people tend to enjoy life and treasure every moment in it for joy and the love in it.
Is a finch a songbird? Finches are conspicuous songbirds throughout the temperate areas of the Northern Hemisphere and South America and in parts of Africa. Indeed, they are among the dominant birds in many areas, in numbers of both individuals and species. What color is a female finch?
Gouldian Finches In general, animals with immaculate head colors -- be they purple, yellow or red -- are male, while those with slightly dingy, black-flecked heads are females. The males of some color forms, such as black-headed variations, usually have brighter neck rings than females do.
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