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. The term, coined by Bernie Krause, refers to one of three components of the soundscape, the others being geophony and anthropophony. The interrelationship of disciplines informed by natural soundscapes is called soundscape ecology, a further refinement of the older model and term, acoustic ecology. The study of biophony focuses on the collective impact of all sounds emanating from natural biological origins in a given habitat. The realm of study is focused on the intricate relationships – competitive and/or cooperative – generally between non-human biological sound sources taking into account seasonal variability, weather, and time of day or night, and climate change. 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 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. The "niche hypothesis", 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 subtropicalrain forests.
