Clutter resilience via auditory stream segregation in echolocating greater mouse-eared bats.

Autor: Pedersen MB; Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark., Beedholm K; Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark., Hubancheva A; Acoustic and Functional Ecology, Max Planck Institute for Biological Intelligence, 82319 Seewiesen, Germany.; National Museum of Natural History, Bulgarian Academy of Sciences, 1000 Sofia, Bulgaria., Koseva K; Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark., Uebel AS; Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark., Hochradel K; Private University for Health Sciences, Medical Informatics and Technology GmbH, 6060 Hall Tirol, Austria., Madsen PT; Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark., Stidsholt L; Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark.; Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, 10315 Berlin, Germany.
Jazyk: angličtina
Zdroj: The Journal of experimental biology [J Exp Biol] 2024 Jun 15; Vol. 227 (12). Date of Electronic Publication: 2024 Jun 21.
DOI: 10.1242/jeb.246889
Abstrakt: Bats use echolocation to navigate and hunt in darkness, and must in that process segregate target echoes from unwanted clutter echoes. Bats may do this by approaching a target at steep angles relative to the plane of the background, utilizing their directional transmission and receiving systems to minimize clutter from background objects, but it remains unknown how bats negotiate clutter that cannot be spatially avoided. Here, we tested the hypothesis that when movement no longer offers spatial release, echolocating bats mitigate clutter by calling at lower source levels and longer call intervals to ease auditory streaming. We trained five greater mouse-eared bats (Myotis myotis) to land on a spherical loudspeaker with two microphones attached. We used a phantom-echo setup, where the loudspeaker/target transmitted phantom clutter echoes by playing back the bats' own calls at time delays of 1, 3 and 5 ms with a virtual target strength 7 dB higher than the physical target. We show that the bats successfully landed on the target, irrespective of the clutter echo delays. Rather than decreasing their source levels, the bats used similar source level distributions in clutter and control trials. Similarly, the bats did not increase their call intervals, but instead used the same distribution of call intervals across control and clutter trials. These observations reject our hypothesis, leading us to conclude that bats display great resilience to clutter via short auditory integration times and acute auditory stream segregation rather than via biosonar adjustments.
Competing Interests: Competing interests The authors declare no competing or financial interests.
(© 2024. Published by The Company of Biologists Ltd.)
Databáze: MEDLINE