Geophony

Terminology

• Geophony, from the Greek prefix, geo, meaning earth-related, and phon, meaning sound, is a neologism used to describe one of three possible sonic components of a soundscape. It relates to the naturally occurring non-biological sounds coming from different types of habitats, whether marine or terrestrial. Typically, geophony refers to the sounds of natural forces, such as water, wind, and thunder, occurring in wild, relatively undisturbed habitats. But geophony is not limited to that narrow definition since these audio sources can be experienced nearly everywhere the effects of wind and water are expressed.
• Biophony is a term introduced by Krause, who in 1998, first began to express the soundscape in terms of its acoustic sources. The biophony refers to the collective acoustic signatures generated by all sound-producing organisms in a given habitat at a given moment. It includes vocalizations that are used for conspecific communication in some cases. Biophony consists of the Greek prefix, bio, meaning life, and the suffix, phon, meaning sound, is a neologism used to describe the collective sound that vocalizing animals create in each given environment. It explores new definitions of animal territory as defined by biophony, and addresses changes in density, diversity, and richness of animal populations. Mapping soundscapes can help to illustrate possible driving mechanisms and provide a valuable tool for urban management and planning. However, quantifying biophony across urban landscapes has proven difficult in the presence of anthrophony, or sounds generated by humans. The metric percent biophony (PB) can be used to quantify biophony while avoiding noise bias. The complete absence of biophony or geophony in a given biome would be expressed as dysphonia (from the Greek meaning the inability to produce a proper collective voice in this case). The niche hypothesis (also known as the acoustic niche hypothesis; ANH), an early version of the term biophony, describes the acoustic bandwidth partitioning process that occurs in still-wild biomes by which non-human organisms adjust their vocalizations by frequency and time-shifting to compensate for vocal territory occupied by other vocal creatures. Thus each species evolves to establish and maintain its own acoustic bandwidth so that its voice is not masked. For instance, notable examples of clear partitioning and species discrimination can be found in the spectrograms derived from the biophonic recordings made in most uncompromised tropical and subtropical rain forests. Additional studies with certain insects and amphibians tend to confirm the hypothesis.
• Anthropophony is another term introduced by Krause along with colleague, Stuart Gage. It represents human generated sound from either humans, themselves, or the electro-mechanical technologies they employ. The term, anthropophony, consisting of the Greek prefix, anthropo, meaning human, and the suffix, phon, meaning sound is a neologism used to describe all sound produced by humans, whether coherent, such as music, theatre, and language, or incoherent and chaotic such as random signals generated primarily by electromechanical means. Anthropophony is divided into two sub-categories. Controlled sound, such as music, language, and theatre, and chaotic or incoherent sound sometimes referred to as noise.