Adaptive vocal behavior drives perception by echolocation in bats

Moss, Cynthia F.; Chiu, Chen; Surlykke, Annemarie

doi:10.1016/j.conb.2011.05.028

Cited by 67 publications

(68 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Each scene is dynamic: the animal and its prey are moving through space, which produces changes in the features of echo returns. The task is further complicated in a cluttered environment where each sonar emission results in a cascade of echoes arriving from different locations, which the bat must organize into a coherent representation Moss et al, 2011;Simmons et al, 1988). Acoustic cues, such as interaural time, intensity and spectral differences, provide information about the direction of a sonar object (Shimozawa et al, 1974;Simmons et al, 1983), whereas echo arrival time provides information about its distance (Ewer, 1945;Simmons, 1973).…”

Section: Introductionmentioning

confidence: 99%

Bats coordinate sonar and flight behavior as they forage in open and cluttered environments

Falk

Jakobsen

Surlykke

et al. 2014

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

Echolocating bats use active sensing as they emit sounds and listen to the returning echoes to probe their environment for navigation, obstacle avoidance and pursuit of prey. The sensing behavior of bats includes the planning of 3D spatial trajectory paths, which are guided by echo information. In this study, we examined the relationship between active sonar sampling and flight motor output as bats changed environments from open space to an artificial forest in a laboratory flight room. Using high-speed video and audio recordings, we reconstructed and analyzed 3D flight trajectories, sonar beam aim and acoustic sonar emission patterns as the bats captured prey. We found that big brown bats adjusted their sonar call structure, temporal patterning and flight speed in response to environmental change. The sonar beam aim of the bats predicted the flight turn rate in both the open room and the forest. However, the relationship between sonar beam aim and turn rate changed in the forest during the final stage of prey pursuit, during which the bat made shallower turns. We found flight stereotypy developed over multiple days in the forest, but did not find evidence for a reduction in active sonar sampling with experience. The temporal patterning of sonar sound groups was related to path planning around obstacles in the forest. Together, these results contribute to our understanding of how bats coordinate echolocation and flight behavior to represent and navigate their environment.

show abstract

Section: Introductionmentioning

confidence: 99%

Bats coordinate sonar and flight behavior as they forage in open and cluttered environments

Falk

Jakobsen

Surlykke

et al. 2014

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Dynamic changes to the acoustic field of view (Jakobsen et al, 2013;Wisniewska et al, 2012) may help echolocating animals inspect their surroundings or lock on to specific targets, shaping the perception of their surroundings via changes in the acoustic gaze (Moss, 2010;Moss et al, 2011). Here, we show that wild Atlantic spotted dolphins seem to increase their vertical biosonar beam width by 50% over a fourfold decrease in range.…”

Section: Discussionmentioning

confidence: 71%

“…The beam width and intensity of emitted signals depend on their spectral and temporal properties and on the acoustic behaviour of the echolocating animal (Moss and Surlykke, 2001). There is increasing evidence that bats and toothed whales exhibit significant control over their biosonar (Jakobsen and Surlykke, 2010;Johnson et al, 2008;Moore et al, 2008;Wisniewska et al, 2012) and it is likely that they actively control the perception of their surroundings through changes in biosonar signals and biosonar field of view (Moss et al, 2011).…”

Section: Introductionmentioning

confidence: 99%

Single-click beam patterns suggest dynamic changes to the field of view of echolocating Atlantic spotted dolphins (Stenella frontalis) in the wild

Jensen

Wahlberg

Beedholm

et al. 2015

Journal of Experimental Biology

View full text Add to dashboard Cite

Echolocating animals exercise an extensive control over the spectral and temporal properties of their biosonar signals to facilitate perception of their actively generated auditory scene when homing in on prey. The intensity and directionality of the biosonar beam defines the field of view of echolocating animals by affecting the acoustic detection range and angular coverage. However, the spatial relationship between an echolocating predator and its prey changes rapidly, resulting in different biosonar requirements throughout prey pursuit and capture. Here, we measured single-click beam patterns using a parametric fit procedure to test whether free-ranging Atlantic spotted dolphins (Stenella frontalis) modify their biosonar beam width. We recorded echolocation clicks using a linear array of receivers and estimated the beam width of individual clicks using a parametric spectral fit, cross-validated with well-established composite beam pattern estimates. The dolphins apparently increased the biosonar beam width, to a large degree without changing the signal frequency, when they approached the recording array. This is comparable to bats that also expand their field of view during prey capture, but achieve this by decreasing biosonar frequency. This behaviour may serve to decrease the risk that rapid escape movements of prey take them outside the biosonar beam of the predator. It is likely that shared sensory requirements have resulted in bats and toothed whales expanding their acoustic field of view at close range to increase the likelihood of successfully acquiring prey using echolocation, representing a case of convergent evolution of echolocation behaviour between these two taxa.

show abstract

“…Bat echolocation is a superior model for studying active perception, because ongoing dynamic adaptation of echolocation signals provides a direct window to scene analysis in a naturally behaving animal (32)(33)(34), allowing general inferences for active motor response to perceptual sensory feedback. The acoustic and behavioral median reaction times of around 80-90 ms (Figs.…”

Section: Discussionmentioning

confidence: 99%

Fast sensory–motor reactions in echolocating bats to sudden changes during the final buzz and prey intercept

Geberl

Brinkløv

Wiegrebe

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

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.ost sensory systems passively sample the environment by relying on extrinsic energy sources like light or sound to stimulate sensory receptors. Truly active senses, e.g., the electric sense of weakly electric fishes (1) and echolocation (2), where the animal itself produces the energy used to probe the surroundings, are rare (3). The advanced echolocation systems of bats and toothed whales involve dynamic adaptation of the outgoing sound and behavior based on perception of the surroundings through information processing of returning echoes.The temporal pattern of echolocation signals during prey pursuit changes through three phases: search, approach, and terminal buzz. The buzz, immediately preceding prey capture, is characterized by a dramatic increase in signal repetition rate and is universally present in both bats and whales capturing moving prey (4-8). Repetition rates up to 640 Hz have been reported for porpoises and, contrary to bats, odontocete buzzes usually continue beyond prey contact (6). The buzz of many vespertilionid and molossid bats has two distinct subphases: buzz I with decreasing call durations and intervals, followed by buzz II, with a constant maximum call repetition rate and a characteristic frequency drop of up to an octave (4,(9)(10)(11)(12)(13)(14).The function of the terminal buzz is still not understood (15). It has been hypothesized that odontocete buzzes not only track prey before capture (7), but may also serve to follow escaping prey (6). Bat buzzes have also been hypothesized to help track ev...

show abstract

Adaptive vocal behavior drives perception by echolocation in bats

Cited by 67 publications

References 39 publications

Bats coordinate sonar and flight behavior as they forage in open and cluttered environments

Bats coordinate sonar and flight behavior as they forage in open and cluttered environments

Single-click beam patterns suggest dynamic changes to the field of view of echolocating Atlantic spotted dolphins (Stenella frontalis) in the wild

Fast sensory–motor reactions in echolocating bats to sudden changes during the final buzz and prey intercept

Contact Info

Product

Resources

About