Everything about Bioacoustics totally explained
Bioacoustics is a cross-disciplinary
science that combines
biology and
acoustics. Usually it refers to the investigation of
sound production, dispersion through elastic
media, and reception in
animals, including
humans. This involves
neurophysiological and
anatomical basis of sound production and detection, and relation of acoustic
signals to the
medium they disperse through. The findings give us some evidence about the
evolution of acoustic mechanisms, and from that, the evolution of animals that employ them.
In
underwater acoustics and fisheries acoustics the term is also used to mean the effect of
plants and animals on sound propagated underwater, usually in reference to the use of
sonar technology for
biomass estimation
History
Man has for a long time employed animal sounds to recognise and find them. Bioacoustics as a
scientific discipline was established by the
Slovenian biologist
Ivan Regen. On
31 August 1925 he used a special
stridulatory device to play in a duet with an
insect. Later he put a male
cricket behind a microphone and female crickets in front of a loudspeaker. The females were not moving towards the male but towards the loudspeaker.
The most recent advances in bioacoustics concern the relationships among the animals and their environment and the impact of anthropogenic
noise.
Methods in bioacoustics
Listening is still one of the main methods used in bioacoustical research. Little is known about neuropyhsiological processes that play a role in production, detection and interpretation of sounds in animals, so
animal behaviour and the signals themselves are used for gaining insight into these processes.
Acoustic signals
An experienced observer can use animal sounds to recognize a "singing" animal
species, its location and condition in nature. Investigation of animal sounds also includes signal recording with electronic recording equipment. Due to the wide range of signal properties and media they propagate through, specialized equipment may be required instead of the usual
microphones, such as
hydrophone (underwater sounds),
ultrasound detector (very high-
frequency sounds), or
laser vibrometer (substrate-borne vibrational signals).
Computers are used for storing and analysis of recorded sounds. Specialized sound-editing
software is used for describing and sorting signals according to their
intensity,
frequency, duration and other parameters.
Animal sound collections, managed by
museums of natural history and other institutions, are an important tool for systematic investigation of signals.
Sound production, detection, and use in animals
Scientists in the field of bioacoustics are interested in anatomy and neurophysiology of
organs involved in sound production and detection, including their shape,
muscle action, and activity of
neuronal networks involved. Of special interest is coding of signals with
action potentials in the latter.
But since the methods used for neurophysiological research are still fairly complex and understanding of relevant processes is incomplete, more trivial methods are also used. Especially useful is observation of behavioural responses to acoustic signals. One of such is
phonotaxy - directional movement towards the signal source. By observing response to well defined signals in controlled environment, we can gain insight into signal function,
sensitivity of the hearing apparatus,
noise filtering capability, etc.
Biomass estimation
Biomass estimation uses
sonar to detect
fish, etc. Lower, but still in ultrasound, are sounds used by
bats for
echolocation. On the other side of the frequency spectrum are low frequency-vibrations, often not detected by
hearing organs, but with other, less specialized sense organs. The examples include ground vibrations produced by
elephants whose principal frequency component is around 15 Hz, and low- to medium-frequency substrate-borne vibrations used by most
insect orders. Many animal sounds, however, do fall within the frequency range detectable by a human ear, between 50 and 15,000 Hz. Mechanisms for sound production and detection are just as diverse as the signals themselves.
Further Information
Get more info on 'Bioacoustics'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://bioacoustics.totallyexplained.com">Bioacoustics Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
