The niche hypothesis, also known as the acoustic niche hypothesis (ANH), is an early version of the term biophony. The term 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.
- Eric Stonea (2000), "Separating the Noise from the Noise: A Finding in Support of the 'Niche Hypothesis,' That Birds are Influenced by Human-Induced Noise in Natural Habitats" Anthroös, Vol 13, Issue 4, pgs 225-231
- Luis J. Villanueva-Rivera (2014)." Eleutherodactylus frogs show frequency but no temporal partitioning: implications for the acoustic niche hypothesis," Forestry and Natural Resources, Purdue University, West Lafayette, IN, USA.
- Jerome Sueur (2001). "Cicada acoustic communication: potential sound partitioning in a multispecies community from Mexico (Hemiptera: Cicadomorpha: Cicadidae)," Biological Journal of the Linnean Society, 2002, 75, 379–394. France.
- Krause, Bernie (1998). Into a Wild Sanctuary. Berkeley, California: Heyday Books.
- Krause, Bernie (2002). Wild Soundscapes: Discovering the Voice of the Natural World. Berkeley, California: Wilderness Press.
- Krause, Bernie (31 January 2001). Loss of Natural Soundscape: Global Implications of Its Effect on Humans and Other Creatures. World Affairs Council, San Francisco, California.
- Bernie Krause, Stuart H. Gage, Wooyeong Joo, Measuring and interpreting the temporal variability in the soundscape at four places in Sequoia National Park, Landscape Ecology, DOI 10.1007/s10980-011-9639-6, Aug. 2011,
- Hull J (18 February 2007). "The Noises of Nature". Idea Lab. New York Times Magazine.
- Krause B (2008). "Anatomy of the Soundscape". Journal of the Audio Engineering Society. 56 (1/2).
- Bryan C. Pijanowski, Luis J. Villanueva-Rivera, Sarah L. Dumyahn, Almo Farina, Bernie L. Krause, Brian M. Napoletano, Stuart H. Gage, and Nadia Pieretti,Soundscape Ecology: The Science of Sound in the Landscape, BioScience, March, 2011, Vol. 61 No. 3, 203-216