Research area
We study the sensory physiology and behavioral ecology of bats with special focus on how they use and produce sound to navigate, find food, avoid predators and communicate. Primary areas of investigation include biosonar, sound production, beharioural and sensing strategies in Chiroptera, and hearing and ultrasound detection in moths. We pursue an integrative biology approach to experiments at an organismal level with emphasis on how animals work in an evolutionary context.
Research Leader
Research Group
We have developed microphone array (use of many microphones) methods to study the intensity and beam shape of the sound beam of echolocating bats in the field. We work both in Denmark (Fig. 1 Myotis Skovsøen) and in the tropics, where we have a long-term ongoing collaboration with researchers in Panama to study behavioral ecology of different species tropical bats. We have found that bats are the loudest animals recorded so far.
We study the echolocation and biosonar beam shape of bats from four different species, Myotis daubentonii, Noctilio leporinus, Micronycteris microtis and Macrophyllum macrophyllum (Fig.2). The two first emit their sonar calls through the mouth, but the two last have complicated noseleaves and emit sounds through the nostrils (link to movie 1). We to inspire the construction of biomimetic robots orienting by echolocation (Fig.3). This project has been funded by the EU through a FP 7 Cognitive Systems grant to a international consortium (www.chiroping.org).
We use Daubenton’s bat Myotis daubentonii to study general issues like reaction time and active motor control to dynamically adapt perception. We have designed a set-up where we can suddenly remove prey from the sonar ”vision” of a bat hunting for prey on the wing over an artificial pond in the lab (link to movie2). We collaborate with colleagues from Munich University (Prof. Lutz Wiegrebe, Ph.d.student Conny Gerbel) on this project. They perform similar experiments in the field (link to movie 3). Most of the projects we are involved in focus on bats, but we also work on moths (the prey of bats) in collaboration with colleagues from Japan. We have shown that a number of moths produce very quiet sound for ”private” communication.
Publications
Moss, C.F., Chiu, C., Surlykke, A. (2011). Adaptive vocal behavior drives perception by echolocation in bats. Current Opinion in Neurobiology. Special issue on Sensory and Motor Systems. 21: 645-652. DOI: 10.1016/j.conb.2011.05.028.
Guarato F., Jakobsen L., Vanderelst, D., Surlykke, A. and Hallam J. (2011). A method for estimating the orientation of a directional sound source from source directivity and multi-microphone recordings: {P}rinciples and application. J. Acoust. Soc. Am. 129 (2): 1046-1058. New method for determining directivity.
Ratcliffe J.M., Jakobsen, L., Kalko, E.K.V., Surlykke, A. (2011). Frequency alternation and an offbeat rhythm indicate foraging behavior in the echolocating bat, Saccopteryx bilineata. J. Comp. Physiol. A DOI: 10.1007/s00359-011-0630-0.
Wilson, M., Schack, H.B., Madsen, P.T., Surlykke, A., Wahlberg, M. (2011). Directional escape behavior and energy detection in allis shad (Alosa alosa) exposed to ultrasonic clicks mimicking an approaching toothed whale. J. Exp. Biol. 214: 22-29. DOI: 10.1242/jeb.043323.
Brinkløv, S., Jakobsen, L., Ratcliffe, J.M., Kalko, E.K.V., Surlykke, A. (2011). Echolocation call intensity and directionality in flying short-tailed fruit bats, Carollia perspicillata (Phyllostomidae). J. Acoust. Soc. Am. 129 (1): 427-435. DOI: 10.1121/1.3519396. * First determination of sonar beam shape in flying nose-emitting bats.
Takanashi, T., Nakano, R., Surlykke, A., Tatsuta, H., Tabata, J. Ishikawa, Y., Skals, N. (2010). Variation in Courtship Ultrasounds of Three Ostrinia Moths with Different Sex Pheromones. PLoS ONE 5 (10): e13144. DOI: 10.1371/journal.pone.0013144.
Moss, C.F., Surlykke, A. (2010). Probing the Natural Scene by Echolocation Frontiers of Behavioral Neuroscience, Special issue on Neuroethology. DOI: 10.3389/fnbeh.2010.00033. ** Scene analysis and perception through echolocation.
Brinkløv, S., Kalko, E.K.V., Surlykke, A. (2010). Dynamic adjustment of biosonar intensity to habitat clutter in the bat Macrophyllum macrophyllum (Phyllostomidae). Behav. Ecol. Sociobiol. 64:1867-1874. DOI: 10.1007/s00265-010-0998-9. * First study relating emitted intensity to habitat constraints.
Jakobsen, L., Surlykke, A. (2010). Vespertilionid bats control the width of their biosonar sound beam dynamically during prey pursuit. PNAS 107 (31). 13930-13935. DOI: 10.1073/pnas.1006630107. ** Demonstrates FLEXIBLE directionality of a sound signal.
Nakano, R., Takanashi, T., Skals, N., Surlykke, A., Ishikawa, Y. (2010). To females of a noctuid moth, male courtship songs are nothing more than bat echolocation calls. Biol. Lett. 6, 582-584. DOI: 10.1098/rsbl.2010.0058. * Sensory AND behavioral exploitation: Male moths exploit females' bat-defense for successful mating.