Echolocating greater horseshoe bats (Rhinolophus ferrumequinum) detect insects by concentrating on the characteristic amplitude- and frequency modulation pattern fluttering insects impose on the returning echoes. This study shows that horseshoe bats can also further analyse insect echoes and thus recognize and categorize the kind of insect they are echolocating.
Four greater horseshoe bats were trained in a twoalternative forced-choice procedure to choose the echo of one particular insect species turning its side towards the bat (Fig. 1). The bats were able to discriminate with over 90% correct choices between the reward-positive echo and the echoes of other insect species all fluttering with exactly the same wingbeat rate (Fig. 4).
When the angular orientation of the reward-positive insect was changed (Fig. 2), the bats still preferred these unknown echoes over echoes from other insect species (Fig. 5) without any further training. Because the untrained bats did not show any prey preference, this indicates that the bats were able to perform an aspect-anglein-dependent classification of insects.
Finally we tested what parameters in the echo were responsible for species recognition. It turned out that the bats especially used the small echo-modulations in between glints as a source of information (Fig. 7). Neither the amplitudenor the frequencymodulation of the echoes alone was sufficient for recognition of the insect species (Fig. 8). Bats performed a pattern recognition task based on complex computations of several acoustic parameters, an ability which might be termed cognitive.
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Barclay RMR (1985) Long- versus short-range strategies of hoary (Lasiurus cinereus) and silver-haired (Lasionycteris noctivagans) bats and the consequences. Can J Zool 63:2507–2515
Bell GP, Fenton MB (1984) The use of Doppler-shifted echoes as a flutter detection and clutter rejection system: the echolocation and feeding behavior of Hipposideros ruber. Behav Ecol Sociobiol 15:109–114
Cerella J (1986) Pigeons and perceptions. Pattern Recognition 19:431–438
D'Amato MR, van Sant P (1988) The person concept in monkeys (Cebus apella). J Exp Psychol 14:43–55
Emde G von der, Schnitzler HU (1986) Fluttering target detection in Hipposiderid bats. J Comp Physiol A 159:765–772
Emde G von der, Menne D (1989) Discrimination of insect wingbeat-frequencies by the bat Rhinolophus ferrumequinum. J Comp Physiol A 164:663–671
Fenton MB (1982) Echolocation, insect hearing, and feeding ecology of bats. In: Kunz TH (ed) Ecology of bats. Plenum Press, New York, pp 261–285
Gellermann LW (1933) Chance orders of alternating stimuli in visual discrimination experiments. J Genet Psychol 42:206–208
Goldman LJ, Henson OW Jr (1977) Prey recognition and selection by the constant frequency bat, Pteronotus p. parnellii. Behav Ecol Sociobiol 2:411–419
Heilmann U (1984) Das Frequenzunterscheidungsvermögen bei der Großen Hufeisennase, Rhinolophus ferrumequinum. Thesis, University Tübingen
Herrnstein RJ (1985) Riddles of natural categorization. Phil Trans R Soc Lond B 308:129–144
Herrnstein RJ, Loveland DH, Cable C (1976) Natural concepts in pigeons. J Exp Psychol: Anim Behav Proc 2:285–302
Irle E, Markowitsch HJ (1987) Conceptualization without specific training in squirrel monkeys (Saimiri sciureus): A test using the non-match-to-sample procedure. J Comp Psychol 101:305–311
Kober R, Schnitzler HU (1990) Information in sonar echoes of fluttering insects available for echolocating bats. J Acoust Soc Am 87:874–881
Long GR, Schnitzler HU (1975) Behavioural audiograms from the bat, Rhinolophus ferrumequinum. J Comp Physiol 100:211–219
Neuweiler G (1983) Echolocation and adaptivity to ecological constraints. In: Huber F, Markl H (eds) Neuroethology and behavioural physiology. Springer, Berlin Heidelberg New York, pp 280–302
Ostwald J (1980) The functional organization of the auditory cortex in the cf-fm bat Rhinolophus ferrumequinum. In: Busnel RG, Fish JF (eds) Animal sonar systems. NATO Advanced Study Institute Series (A) 28. Plenum Press, New York, pp 953–955
Sachs L (1984) Angewandte Statistik. Springer, Berlin Heidelberg New York
Schnitzler HU (1968) Die Ultraschall-Ortungslaute der Hufeisen-Fledermäuse (Chiroptera-Rhinolophidae) in verschiedenen Orientierungssituationen. Z Vergl Physiol 57:376–408
Schnitzler HU (1987) Echoes of fluttering insects — Information for echolocating bats. In: Fenton MB, Racey P, Rayner JMV (eds) Recent advances in the study of bats. Cambridge Univ Press, Cambridge London New York, pp 226–243
Schnitzler HU, Henson OW Jr (1980) Performance of airborne animal sonar systems: I. Microchiroptera. In: Busnel RG, Fish JF (eds) Animal sonar systems, NATO Advanced Studies Institute Series (A) 28. Plenum Press, New York, pp 109–182
Schnitzler HU, Menne D, Kober R, Heblich K (1983) The acoustical image of fluttering insects in echolocating bats. In: Huber F, Markl H (eds) Neuroethology and behavioural physiology. Springer, Berlin Heidelberg New York, pp 235–250
Schnitzler HU, Ostwald J (1983) Adaptations for the detection of fluttering insects by echolocation in horseshoe bats. In: Ewert JP, Capranica RR, Ingle DJ (eds) Advances in vertebrate neuroethology. Plenum Press, New York, pp 801–828
Schuller G (1984) Natural ultrasonic echoes from wing beating insects are encoded by collicular neurons in the CF-FM bat, Rhinolophus ferrumequinum. J Comp Physiol A 155:121–128
Schuller G, Pollak G (1979) Disproportionate frequency representation in the inferior colliculus of Doppler-compensating greater horseshoe bats: Evidence for an acoustic fovea. J Comp Physiol 132:47–54
Sotavalta O (1947) The flight tone (wing stroke frequency) of insects. Acta Entomol Fenn 4:5–117
Trappe M (1982) Verhalten und Echoortung der großen Hufeisennase (Rhinolophus ferrumequinum) beim Insektenfang. Thesis, University Tübingen
Vaughan TA (1977) Foraging behavior of the giant leaf-nosed bat (Hipposideros commersoni). East Afr Wildl J 15:237–249
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von der Emde, G., Schnitzler, HU. Classification of insects by echolocating greater horseshoe bats. J Comp Physiol A 167, 423–430 (1990). https://doi.org/10.1007/BF00192577
- Prey detection
- Pattern recognition
- Concept formation