title: On-board recordings reveal no jamming avoidance in wild bats.
abstract: Animals often deal with situations in which vast sensory input is received simultaneously. They therefore must possess sophisticated mechanisms to select important input and ignore the rest. In bat echolocation, this problem is at its extreme. Echolocating bats emit sound signals and analyse the returning echoes to sense their environment. Bats from the same species use signals with similar frequencies. Nearby bats therefore face the difficulty of distinguishing their own echoes from the signals of other bats, a problem often referred to as jamming. Because bats commonly fly in large groups, jamming might simultaneously occur from numerous directions and at many frequencies. Jamming is a special case of the general phenomenon of sensory segregation. Another well-known example is the human problem of following conversation within a crowd. In both situations, a flood of auditory incoming signals must be parsed into important versus irrelevant information. Here, we present a novel method, fitting wild bats with a miniature microphone, which allows studying jamming from the bat's 'point of view'. Previous studies suggested that bats deal with jamming by shifting their echolocation frequency. On-board recordings suggest otherwise. Bats shifted their frequencies, but they did so because they were responding to the conspecifics as though they were nearby objects rather than avoiding being jammed by them. We show how bats could use alternative measures to deal with jamming instead of shifting their frequency. Despite its intuitive appeal, a spectral jamming avoidance response might not be the prime mechanism to avoid sensory interference from conspecifics.
authors.affiliation: Department of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
authors.forename: Noam
authors.initials: N
authors.lastname: Cvikel
authors.affiliation: Department of Entomology, University of Arizona, Tuscon, AZ 85721, USA.
authors.forename: Eran
authors.initials: E
authors.lastname: Levin
authors.affiliation: Department of Biology, University of Maryland, College Park, MD 20742, USA.
authors.forename: Edward
authors.initials: E
authors.lastname: Hurme
authors.affiliation: Department of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
authors.forename: Ivailo
authors.initials: I
authors.lastname: Borissov
authors.affiliation: Department of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
authors.forename: Arjan
authors.initials: A
authors.lastname: Boonman
authors.affiliation: Department of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
authors.forename: Eran
authors.initials: E
authors.lastname: Amichai
authors.affiliation: Department of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel yossiyovel@hotmail.com.
authors.forename: Yossi
authors.initials: Y
authors.lastname: Yovel
mesh_terms: D000162:Acoustics; D000818:Animals; D002685:Chiroptera / Q000502:physiology*; D004455:Echolocation; D005010:Ethology / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005426:Flight, Animal; D040362:Geographic Information Systems / Q000295:instrumentation*; D008297:Male; D013686:Telemetry / Q000662:veterinary*
keywords: bats; cocktail party; echolocation; jamming; on-board recordings; sensory segregation