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Joachim Ostwald - One of the best experts on this subject based on the ideXlab platform.
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Discrimination of two-wavefront echoes by the big brown bat, Eptesicus fuscus: behavioral experiments and receiver simulations.
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1993Co-Authors: Joachim Mogdans, Hans-ulrich Schnitzler, Joachim OstwaldAbstract:1. Echolocating bats (Eptesicus fuscus) were trained to discriminate between simulated targets consisting of one or two echo-wavefronts with internal time delays of up to 100 μs. Spectral and temporal properties and total signal energy of the targets were evaluated and predictions for performances of bats derived from receiver models were compared with measured performances. 2. Eptesicus fuscus was able to discriminate a one-wavefront target from two-wavefront targets with distinct internal time delays (12 μs, 32–40 μs and 52–100 μs). Performance was not affected by changes in total signal energy. Bats also successfully discriminated between two-wavefront targets with different internal time delays. 3. Performance predicted from differences in total energy between targets did not match the measured performance, indicating that bats did not rely on total echo energy. This finding is also supported by the behavioral data. Performance predicted from spectral and temporal receiver models both matched the measured performance and, therefore, neither one of these models can be favored over the other. 4. The behavioral data suggest that Eptesicus fuscus did not transform echo information into estimates of target range separation and, therefore, did not perceive the two wavefronts of each simulated two-wavefront echo as two separate targets.
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Discrimination of two-wavefront echoes by the big brown bat, Eptesicus fuscus: behavioral experiments and receiver simulations.
Journal of comparative physiology. A Sensory neural and behavioral physiology, 1993Co-Authors: Joachim Mogdans, Hans-ulrich Schnitzler, Joachim OstwaldAbstract:1. Echolocating bats (Eptesicus fuscus) were trained to discriminate between simulated targets consisting of one or two echo-wavefronts with internal time delays of up to 100 microseconds. Spectral and temporal properties and total signal energy of the targets were evaluated and predictions for performances of bats derived from receiver models were compared with measured performances. 2. Eptesicus fuscus was able to discriminate a one-wavefront target from two-wavefront targets with distinct internal time delays (12 microseconds, 32-40 microseconds and 52-100 microseconds). Performance was not affected by changes in total signal energy. Bats also successfully discriminated between two-wavefront targets with different internal time delays. 3. Performance predicted from differences in total energy between targets did not match the measured performance, indicating that bats did not rely on total echo energy. This finding is also supported by the behavioral data. Performance predicted from spectral and temporal receiver models both matched the measured performance and, therefore, neither one of these models can be favored over the other. 4. The behavioral data suggest that Eptesicus fuscus did not transform echo information into estimates of target range separation and, therefore, did not perceive the two wavefronts of each simulated two-wavefront echo as two separate targets.
Hans-ulrich Schnitzler - One of the best experts on this subject based on the ideXlab platform.
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Echo SPL influences the ranging performance of the big brown bat, Eptesicus fuscus.
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1994Co-Authors: Annette Denzinger, Hans-ulrich SchnitzlerAbstract:Four bats of the species Eptesicus fuscus were trained in a two-alternative forced-choice procedure to discriminate between two phantom targets that differed in range. The rewarded stimulus was located at a distance of 52.7 cm, while the other unrewarded stimulus was further away. Only one target was presented at a time.
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Discrimination of two-wavefront echoes by the big brown bat, Eptesicus fuscus: behavioral experiments and receiver simulations.
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1993Co-Authors: Joachim Mogdans, Hans-ulrich Schnitzler, Joachim OstwaldAbstract:1. Echolocating bats (Eptesicus fuscus) were trained to discriminate between simulated targets consisting of one or two echo-wavefronts with internal time delays of up to 100 μs. Spectral and temporal properties and total signal energy of the targets were evaluated and predictions for performances of bats derived from receiver models were compared with measured performances. 2. Eptesicus fuscus was able to discriminate a one-wavefront target from two-wavefront targets with distinct internal time delays (12 μs, 32–40 μs and 52–100 μs). Performance was not affected by changes in total signal energy. Bats also successfully discriminated between two-wavefront targets with different internal time delays. 3. Performance predicted from differences in total energy between targets did not match the measured performance, indicating that bats did not rely on total echo energy. This finding is also supported by the behavioral data. Performance predicted from spectral and temporal receiver models both matched the measured performance and, therefore, neither one of these models can be favored over the other. 4. The behavioral data suggest that Eptesicus fuscus did not transform echo information into estimates of target range separation and, therefore, did not perceive the two wavefronts of each simulated two-wavefront echo as two separate targets.
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Discrimination of two-wavefront echoes by the big brown bat, Eptesicus fuscus: behavioral experiments and receiver simulations.
Journal of comparative physiology. A Sensory neural and behavioral physiology, 1993Co-Authors: Joachim Mogdans, Hans-ulrich Schnitzler, Joachim OstwaldAbstract:1. Echolocating bats (Eptesicus fuscus) were trained to discriminate between simulated targets consisting of one or two echo-wavefronts with internal time delays of up to 100 microseconds. Spectral and temporal properties and total signal energy of the targets were evaluated and predictions for performances of bats derived from receiver models were compared with measured performances. 2. Eptesicus fuscus was able to discriminate a one-wavefront target from two-wavefront targets with distinct internal time delays (12 microseconds, 32-40 microseconds and 52-100 microseconds). Performance was not affected by changes in total signal energy. Bats also successfully discriminated between two-wavefront targets with different internal time delays. 3. Performance predicted from differences in total energy between targets did not match the measured performance, indicating that bats did not rely on total echo energy. This finding is also supported by the behavioral data. Performance predicted from spectral and temporal receiver models both matched the measured performance and, therefore, neither one of these models can be favored over the other. 4. The behavioral data suggest that Eptesicus fuscus did not transform echo information into estimates of target range separation and, therefore, did not perceive the two wavefronts of each simulated two-wavefront echo as two separate targets.
Joachim Mogdans - One of the best experts on this subject based on the ideXlab platform.
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Discrimination of two-wavefront echoes by the big brown bat, Eptesicus fuscus: behavioral experiments and receiver simulations.
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1993Co-Authors: Joachim Mogdans, Hans-ulrich Schnitzler, Joachim OstwaldAbstract:1. Echolocating bats (Eptesicus fuscus) were trained to discriminate between simulated targets consisting of one or two echo-wavefronts with internal time delays of up to 100 μs. Spectral and temporal properties and total signal energy of the targets were evaluated and predictions for performances of bats derived from receiver models were compared with measured performances. 2. Eptesicus fuscus was able to discriminate a one-wavefront target from two-wavefront targets with distinct internal time delays (12 μs, 32–40 μs and 52–100 μs). Performance was not affected by changes in total signal energy. Bats also successfully discriminated between two-wavefront targets with different internal time delays. 3. Performance predicted from differences in total energy between targets did not match the measured performance, indicating that bats did not rely on total echo energy. This finding is also supported by the behavioral data. Performance predicted from spectral and temporal receiver models both matched the measured performance and, therefore, neither one of these models can be favored over the other. 4. The behavioral data suggest that Eptesicus fuscus did not transform echo information into estimates of target range separation and, therefore, did not perceive the two wavefronts of each simulated two-wavefront echo as two separate targets.
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Discrimination of two-wavefront echoes by the big brown bat, Eptesicus fuscus: behavioral experiments and receiver simulations.
Journal of comparative physiology. A Sensory neural and behavioral physiology, 1993Co-Authors: Joachim Mogdans, Hans-ulrich Schnitzler, Joachim OstwaldAbstract:1. Echolocating bats (Eptesicus fuscus) were trained to discriminate between simulated targets consisting of one or two echo-wavefronts with internal time delays of up to 100 microseconds. Spectral and temporal properties and total signal energy of the targets were evaluated and predictions for performances of bats derived from receiver models were compared with measured performances. 2. Eptesicus fuscus was able to discriminate a one-wavefront target from two-wavefront targets with distinct internal time delays (12 microseconds, 32-40 microseconds and 52-100 microseconds). Performance was not affected by changes in total signal energy. Bats also successfully discriminated between two-wavefront targets with different internal time delays. 3. Performance predicted from differences in total energy between targets did not match the measured performance, indicating that bats did not rely on total echo energy. This finding is also supported by the behavioral data. Performance predicted from spectral and temporal receiver models both matched the measured performance and, therefore, neither one of these models can be favored over the other. 4. The behavioral data suggest that Eptesicus fuscus did not transform echo information into estimates of target range separation and, therefore, did not perceive the two wavefronts of each simulated two-wavefront echo as two separate targets.
Marianne Volleth - One of the best experts on this subject based on the ideXlab platform.
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Taxonomic position of “Pipistrellus societatis” Hill, 1972 and the karyological characteristics of the genus Eptesicus (Chiroptera: Vespertilionidae)
Journal of Zoological Systematics and Evolutionary Research, 2009Co-Authors: Klaus-gerhard Heller, Marianne VollethAbstract:Summary Recently collected material (five specimens from Ulu Gombak, Malaysia) shows that Pipistrellus societatis Hill 1972 has to be considered as a lowland form of P. circumdatus Temminck 1840. Chromosomal analysis (2n = 50, FN = 48) and examination of the baculum prove that Pipistrellus circumdatus has to be placed in the genus Eptesicus. Karyological and morphological differences of the genera Vespertilio, Pipistrellus and Eptesicus are discussed. Extension of the definitions of these genera is proposed, taking into consideration karyological characteristics and the form of the baculum. The number of premolars is considered less significant. Zusammenfassung Die taxonomische Stellung von «Pipistrellus societatis» Hill, 1972 und die karyologischen Merkmale der Gattung Eptesicus (Chiroptera: Vespertilionidae) Anhand von neu gesammeltem Material (funf Exemplare aus Ulu Gombak /Malaysia) wird gezeigt, dasPipistrellus societatis Hill, 1972 als Tieflandform von Pipistrellus circumdatus Temminck, 1840 zu betrachten ist. Aus der Chromosomenanalyse (2n = 50, FN = 48) and der Untersuchung des Baculums geht hervor, dasP. circumdatus in die Gattung Eptesicus zu stellen ist. Die karyologischen and morphologischen Unterschiede der Gattungen Vespertilio, Pipistrellus und Eptesicus werden diskutiert. Es wird eine Erweiterung der Definitionen dieser Gattungen unter Einbeziehung der karyologischen Merkmale and der Baculumform vorgeschlagen. Der Anzahl der Pramolaren wird dabei weniger Wert beigemessen.
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taxonomic position of pipistrellus societatis hill 1972 and the karyological characteristics of the genus Eptesicus chiroptera vespertilionidae
Journal of Zoological Systematics and Evolutionary Research, 2009Co-Authors: Klaus-gerhard Heller, Marianne VollethAbstract:Summary Recently collected material (five specimens from Ulu Gombak, Malaysia) shows that Pipistrellus societatis Hill 1972 has to be considered as a lowland form of P. circumdatus Temminck 1840. Chromosomal analysis (2n = 50, FN = 48) and examination of the baculum prove that Pipistrellus circumdatus has to be placed in the genus Eptesicus. Karyological and morphological differences of the genera Vespertilio, Pipistrellus and Eptesicus are discussed. Extension of the definitions of these genera is proposed, taking into consideration karyological characteristics and the form of the baculum. The number of premolars is considered less significant. Zusammenfassung Die taxonomische Stellung von «Pipistrellus societatis» Hill, 1972 und die karyologischen Merkmale der Gattung Eptesicus (Chiroptera: Vespertilionidae) Anhand von neu gesammeltem Material (funf Exemplare aus Ulu Gombak /Malaysia) wird gezeigt, dasPipistrellus societatis Hill, 1972 als Tieflandform von Pipistrellus circumdatus Temminck, 1840 zu betrachten ist. Aus der Chromosomenanalyse (2n = 50, FN = 48) and der Untersuchung des Baculums geht hervor, dasP. circumdatus in die Gattung Eptesicus zu stellen ist. Die karyologischen and morphologischen Unterschiede der Gattungen Vespertilio, Pipistrellus und Eptesicus werden diskutiert. Es wird eine Erweiterung der Definitionen dieser Gattungen unter Einbeziehung der karyologischen Merkmale and der Baculumform vorgeschlagen. Der Anzahl der Pramolaren wird dabei weniger Wert beigemessen.
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systematic implications of chromosome gtg band and bacula morphology for southern african Eptesicus and pipistrellus and several other species of vespertilioninae chiroptera vespertilionidae
Acta Chiropterologica, 2002Co-Authors: Teresa Kearney, Marianne Volleth, G Contrafatto, Peter J TaylorAbstract:Phylogenetic analyses of bacular and chromosomal GTG-band characters verify the suggestion that Eptesicus hottentotus (A. Smith, 1833) is the only true Eptesicus Rafinesque, 1820 of the six southern African species (capensis, cf. melckorum, rendalli, somalicus and zuluensis) formerly classified as Eptesicus. GTG-banded chromosomes studied in rendalli, zuluensis and capensis confirm the affiliation of all of them to the genus Neoromicia; these species were previously placed in the Pipistrellus Kaup, 1829, subgenus Neoromicia based on bacular morphology. For karyological reasons, the elevation of the subgenus Neoromicia to generic rank is established by the presence of three Robertsonian fusion chromosomes (7/11, 8/9, 10/12) as distinguishing characters. The move of Hypsugo nanus and cf. melckorum to the genus Neoromicia is indicated by chromosomal analysis and bacular morphology, respectively. The close phylogenetic relationship between Pipistrellus cf. kuhlii and P. rusticus is shown by a shared Robertson...
Annemarie Surlykke - One of the best experts on this subject based on the ideXlab platform.
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Target ranging and the role of time-frequency structure of synthetic echoes in big brown bats, Eptesicus fuscus
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1992Co-Authors: Annemarie SurlykkeAbstract:Echolocating bats judge the distance to a target on basis of the delay between the emitted cry and the returning echo. In a phantom echo set-up it was investigated how changes in the time-frequency structure of synthetic echoes affect ranging accuracy of big brown bats, Eptesicus fuscus.