title: Fast sensory-motor reactions in echolocating bats to sudden changes during the final buzz and prey intercept.
abstract: Echolocation is an active sense enabling bats and toothed whales to orient in darkness through echo returns from their ultrasonic signals. Immediately before prey capture, both bats and whales emit a buzz with such high emission rates (≥ 180 Hz) and overall duration so short that its functional significance remains an enigma. To investigate sensory-motor control during the buzz of the insectivorous bat Myotis daubentonii, we removed prey, suspended in air or on water, before expected capture. The bats responded by shortening their echolocation buzz gradually; the earlier prey was removed down to approximately 100 ms (30 cm) before expected capture, after which the full buzz sequence was emitted both in air and over water. Bats trawling over water also performed the full capture behavior, but in-air capture motions were aborted, even at very late prey removals (<20 ms = 6 cm before expected contact). Thus, neither the buzz nor capture movements are stereotypical, but dynamically adapted based on sensory feedback. The results indicate that echolocation is controlled mainly by acoustic feedback, whereas capture movements are adjusted according to both acoustic and somatosensory feedback, suggesting separate (but coordinated) central motor control of the two behaviors based on multimodal input. Bat echolocation, especially the terminal buzz, provides a unique window to extremely fast decision processes in response to sensory feedback and modulation through attention in a naturally behaving animal.
authors.affiliation: Department of Biologie II, Division of Neurobiology, Ludwig Maximilians University, 82152 Martinsried, Germany; and.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Geberl
authors.affiliation: Department of Biology, University of Southern Denmark, 5230 Odense M, Denmark.
authors.forename: Signe
authors.initials: S
authors.lastname: Brinkløv
authors.affiliation: Department of Biologie II, Division of Neurobiology, Ludwig Maximilians University, 82152 Martinsried, Germany; and.
authors.forename: Lutz
authors.initials: L
authors.lastname: Wiegrebe
authors.affiliation: Department of Biology, University of Southern Denmark, 5230 Odense M, Denmark ams@biology.sdu.dk.
authors.forename: Annemarie
authors.initials: A
authors.lastname: Surlykke
mesh_terms: D000162:Acoustics; D000819:Animal Communication; D000818:Animals; D002685:Chiroptera / Q000502:physiology*; D003657:Decision Making; D004455:Echolocation; D025461:Feedback, Physiological; D005426:Flight, Animal; D011235:Predatory Behavior / Q000502:physiology*; D014741:Video Recording; D014828:Vocalization, Animal
keywords: bat; buzz; decision; echolocation; sensory motor