Bei Interesse an spezifischen Publikationen wenden Sie sich bitte direkt an die Autoren.

 

2024

MORGENTHAL K., KRÜGER Y., ROGERS T., DEHNHARDT G. & HANKE F.D. (2024). Characterization of pinniped vibrissal type and number. Marine Mammal Science DOI.org/10.1111/mms.13166

2023

HÜTTNER T., VON FERSEN L., MIERSCH M. & DEHNHARDT G. (2023). Passive electroreception in bottlenose dolphins (Tursiops truncatus): implication for micro- and large-scale orientation. Journal of Experimental Biology (2023) 226, jeb245845 DOI:10.1242/jeb.245845

2022

NIESTEROK B., MARTN S., HILDEBRANDT L., DEHNHARDT G. & HANKE F.D. (2022). Well-developed spatial reversal learning abilities in harbor seals (Phoca vitulina). Animal Cognition 25(5):1195-1206 DOI:10.1007/s10071-022-01651-3 (Special issue “Marine mammal cognition”, Access online)

ERDSACK N., DEHNHARDT G. & HANKE F.D. (2022). Serial visual reversal learning in harbor seals (Phoca vitulina). Animal Cognition 25(5):1183-1193 DOI:10.1007/s10071-022-01653-1 (Special issue “Marine mammal cognition”, Access online)

2021

BUBLITZ A., DEHNHARDT G. & HANKE F.D. (2021). Reversal of Spatial Discrimination Task in the Common Octopus (Octopus vulgaris). In: frontiers in Behavioral Neuroscience, vol. 15. DOI:10.3389/fnbeh.2021.614523

2020

HANKE W., MEYER S., BLECKMANN H. & DEHNHARDT G. (2020). Hydrodynamic reception in the Australian water rat, Hydromys chrysogaster. In: Journal of Comparative Physiology A. DOI:10.1007/s00359-020-01416-8

DEHNHARDT G., MIERSCH L., MARSHALL C.D., VON FERSEN L. & HÜTTNER T. (2020). Passive Electroreception in Mammals. In: Fritzsch, B. (Ed.) and Bleckmann, H. (Volume Editor), The Senses: A Comprehensive Reference, vol. 7. Elsevier, Academic Press, pp. 385–392

2018

HANKE F.D. & DEHNHARDT G. (2018). On route with harbor seals - how their senses contribute to orientation, navigation, and foraging. Neuroforum 24(4):1-15 DOI:10.1515/nf-2018-A012

KRÜGER Y., HANKE W., MIERSCH L. & DEHNHARDT G. (2018). Detection and direction discrimination of single vortex rings by harbor seals (Phoca vitulina). Journal of Experimental Biology 221: DOI:10.1242/jeb.170753

2017

NIESTEROK B., DEHNHARDT G., & HANKE W. (2017). Hydrodynamic sensory threshold in harbour seals (Phoca vitulina) for artificial flatfish breathing currents. Journal of Experimental Biology 220:2364-2371

GEURTEN B.R.H, NIESTEROK B., DEHNHARDT G. & HANKE F.D. (2017). Saccadic movement strategy in an aquatic species - the harbor seal (Phoca vitulina). Journal of Experimental Biology 220:1503-1508

BUBLITZ A., WEINHOLD S.R., STROBEL S., DEHNHARDT G. & HANKE F.D. (2017). Reconsideration of serial visual reversal learning in the common octopus (Octopus vulgaris) from a methodological perspective. Frontiers in Physiology 8:54 DOI:10.3389/fphys.2017.00054

DEHNHARDT G. & HANKE F.D. (2017). Whiskers. In: Thewissen, H. (Ed.) Encyclopedia of Marine Mammals.1074-1077

NIESTEROK B., KRÜGER Y., WIESKOTTEN S., DEHNHARDT G. & HANKE W. (2017). Hydrodynamic detection and localization of artificial flatfish breathing currents by harbour seals (Phoca vitulina). Journal of Experimental Biology 220:174-185

HELMER D., GEURTEN B.R.H., DEHNHARDT G.& HANKE F.D. (2017). Saccadic movement strategy in common cuttlefish (Sepia officinalis). Frontiers in Physiology 7:660 DOI:10.3389/fphys.2016.00660

2016

BYL J., MIERSCH L. & DEHNHARDT G. (2016). Underwater sound localization of pure tones in the median plane by harbor seals (Phoca vitulina). Journal of the Acoustical Society of America 140:4490-4495

HEINRICH T., DEHNHARDT G. & HANKE F.D. (2016). Harbor seals (Phoca vitulina) are able to time precisely. Animal Cognition 19(6):1133-1142 DOI:10.1007/s10071-016-1020-3

RAVIGNANI A., FITCH W.T., HANKE F.D., HEINRICH T., HURGUTISCH B., KOTZ S.A., SCHARFF C., STOEGER A.S. & DE BOER B. (2016). What pinnipeds have to say about human music, speech and evolution of rhythm. Frontiers in Neuroscience DOI:10.3389/fnins.2016.00274

HANKE W. & DEHNHARDT G. (2016). Vibrissal touch in seals. In: Prescott, Ahizar, Izhikevich (Eds.) Scholarpedia of Touch, Atlantis Press, pp 125-139

NUMBERGER D., HERLEMANN D., JÜRGENS K., DEHNHARDT G., SCHULZ-VOGT H. (2016). Comparative analysis of the fecal bacterial community of five harbor seals (Phoca vitulina). MicrobiologyOpen 5(5):782-792

MORRISON H.E., BREDE M., DEHNHARDT G. & LEDER A (2016). Simulating the flow and trail following capabilities of harbour seal vibrissae with the Lattice Boltzman Method. Journal of Computational Sciences 17:394-402

WOHLERT D., KRÜGER J., WITT M., SCHMITT O., WREE A., CZECH-DAMAL N., SIEBERT U., FOLKOW L. & HANKE F.D. (2016). Comparative morphometric analysis of three cranial nerves in two phocid seals: the hooded seal (Cystophora cristata) and the harbor seal (Phoca vitulina). The Anatomical Record 299(3):370-378

HANKE F.D. & Dehnhardt G. (2016). Visual and hydrodynamic flow perception (Chapter 13). In: Castellini, Melish (Eds.) Marine mammal physiology - requisites for ocean living. Taylor & Francis, Boca Raton, pp 269-292

2015

KILIAN M., DEHNHARDT G. & HANKE F.D. (2015). How harbor seals (Phoca vitulina) pursue schooling herring. Mammalian Biology 80(5):385-389 DOI:10.1016/j.mambio.2015.04.004

HANKE W. & DEHNHARDT G. (2015). Vibrissal touch in seals. Peer-reviewed open access encyclopedia Scholarpedia. http://www.scholarpedia.org/article/Vibrissal_touch_in_seals

ERDSACK N., DEHNHARDT G, WREE W., WITT A., SIEBERT U. & HANKE W. (2015). Unique fur and skin structure of harbour seals (Phoca vitulina) – thermal insulation, drag reduction, or both? Journal of the Royal Society Interface 12(104):20141206 DOI:10.1098/rsif.2014.1206

SCHOLTYSSEK C., KELBER A. & DEHNHARDT G. (2015). Why do seals have cones? Behavioural evidence for colourblindness in harbour seals. Animal cognition 18(2):551-560 DOI:10.1007/s10071-014-0823-3

DOHMEN M., PIETRZYK U., WIESE H., RECKFORT J., HANKE F.D., ZILLES K., AMUNTS K. & AXER M. (2015). Understanding fiber mixture by simulation in 3D Polarized Light Imaging. NeuroImage 111:464-475 DOI:10.1016/j.neuroimage.2015.02.020

2014

WEIFFEN M., MAUCK B., DEHNHARDT G. & HANKE F.D. (2014). Sensitivity of a harbor seal (Phoca vitulina) to coherent visual motion in random dot displays. SpringerPlus 3:688 DOI:10.1186/2193-1801-3-688

GLÄSER N., MAUCK B., KANDIL F.I., LAPPE M., DEHNHARDT G. & HANKE F.D. (2014). Harbour seals (Phoca vitulina) can perceive optic flow underwater. PLoS ONE 9(7):e103555 DOI:10.1371/journal.pone.0103555

DEHNHARDT G., HANKE W., WIESKOTTEN S., KRÜGER Y. & MIERSCH L. (2014). Hydrodynamic perception in seals and sea lions. In: Flow sensing in air and water, H. Bleckmann (editor), Springer, Berlin Heidelberg, pp 147-167

MARSHALL C.D., WIESKOTTEN S., HANKE W., HANKE F.D., MARSH A., KOT B. & DEHNHARDT G. (2014). Feeding kinematics, suction, and hydraulic jetting performance in harbor seals (Phoca vitulina). PLoS ONE 9(1): e86710 DOI:10.1371/journal.pone.0086710

ERDSACK N., DEHNHARDT G. & HANKE W. (2014). Thermoregulation of the vibrissal system in harbor seals (Phoca vitulina) and Cape fur seals (Arctocephalus pusillus pusillus). Journal of Experimental Marine Biology and Ecology 452: 111-118. DOI:10.1016/j.jembe.2013.12.011

2013

ERDSACK N., DEHNHARDT G. & HANKE W. (2013). Coping with heat: Function of the natal coat of Cape fur seal (Arctocephalus pusillus pusillus) pups in maintaining core body temperature. PLoS ONE 8(8): e72081. DOI:10.1371/journal.pone.0072081

SCHOLTYSSEK C., KELBER A., HANKE F. D. & DEHNHARDT G. (2013). Same different concept formation in a harbor seal (Phoca vitulina). Animal Cognition DOI:10.1007/s10071-013-0624-0

SCHOLTYSSEK C. & DEHNHARDT G. (2013). Brightness discrimination in a South African fur seal (Arctocephallus pusillus). Vision Research 84: 26-32

HANKE W., MARSHALL C. & DEHNHARDT G. (2013). Hydrodynamic perception in true seals (Phocidae) and eared seals (Otariidae), Journal of Comparative Physiology A 199: 421-440

GRANT R., WIESKOTTEN S., WENGST N., PRESCOTT T. & DEHNHARDT G. (2013). Haptic performance of the pinniped vibrissal system. Journal of Comparative Physiology 199: 521-533

CZECH-DAMAL N., MANGER P., DEHNHARDT G. & HANKE W. (2013). Electroreception in aquatic mammals. Journal of Comparative Physiology A 199: 555-563

HANKE F. D., MIERSCH L., WARRANT E., MITSCHKE F. D. & DEHNHARDT G. (2013). Are harbour seals (Phoca vitulina) able to perceive and use polarised light? Journal of Comparative Physiology A 199: 509-519

2012

NIESTEROK B. & HANKE W. (2012). Hydrodynamic patterns from fast-starts in teleost fish and their possible relevance to predator-prey interactions. Journal of Comparative Physiology A 199: 139-149

HANKE W., WIESKOTTEN S., NIESTEROK B, MIERSCH L., WITTE M., BREEDE M., LEDER A. & DEHNHARDT G. (2012). Hydrodynamic perception in pinnipeds. In: Nature-inspired fluid mechanics, C. Tropea and H. Bleckmann (editors). Springer, Berlin Heidelberg, pp 225-240

WITTE M., HANKE W., WIESKOTTEN S., MIERSCH L., BREDE M., DEHNHARDT G. & LEDER A. (2012). On the wake flow dynamics behind harbor seal vibrissae - a fluid mechanical explanation for an extraordinary capability. In: Nature-inspired fluid mechanics, C. Tropea and H. Bleckmann (editors). Springer, Berlin Heidelberg, pp 241-263

ERDSACK N., HANKE F. D., DEHNHARDT G. & HANKE W. (2012). Control and amount of heat dissipation through thermal windows in harbor seals (Phoca vitulina). Journal of Thermal Biology 37 (7): 537–544

CZECH-DAMAL N., LIEBSCHNER A., MIERSCH L., KLAUER G., HANKE F. D., MARSHALL C., DEHNHARDT G. & HANKE W. (2012). Electroreception in the Guiana dolphin (Sotalia guianensis). Proceedings of the Royal Society B - Biological Sciences 279: 663-668

2011

MIERSCH L., HANKE W., WIESKOTTEN S., HANKE F. D., OEFFNER J., LEDER A., BREDE M., WITTE M. & DEHNHARDT G. (2011). Flow sensing by pinniped whiskers. Philosophical Transactions of the Royal Society B 366: 3077-3084

WIESKOTTEN S., MAUCK B., MIERSCH L., DEHNHARDT G. & HANKE W. (2011). Hydrodynamic discrimination of wakes caused by objects of different size or shape in a harbour seal (Phoca vitulina). The Journal of Experimental Biology 214: 1922-1930

HANKE F. D., SCHOLTYSSEK C., HANKE W. & DEHNHARDT G. (2011). Contrast sensitivity in a harbor seal (Phoca vitulina). Journal of Comparative Physiology A 197(2): 203-210

GLÄSER N., OTTER C., WIESKOTTEN S., DEHNHARDT G. & HANKE W. (2011). Hydrodynamic trail following in a California sea lion (Zalophus californianus). Journal of Comparative Physiology A 197:141-151

2010

WIESKOTTEN S., DEHNHARDT G., MAUCK B., MIERSCH L. & HANKE W. (2010). The impact of glide phases on the trackability of hydrodynamic trails in harbour seals (Phoca vitulina). The Journal of Experimental Biology 213:3734-3740

HANKE W., WITTE M., MIERSCH L., BREDE M., OEFFNER J., MICHAEL M., HANKE F. D., LEDER A. & DEHNHARDT G. (2010). Harbor seal vibrissae morphology suppresses vortex-induced vibrations. The Journal of Experimental Biology 213: 2665-2672

WIESKOTTEN S., DEHNHARDT G., MAUCK B., MIERSCH L. & HANKE W. (2010). Hydrodynamic determination of the moving direction of an artificial fin by a harbour seal (Phoca vitulina). The Journal of Experimental Biology 213: 2194-2200

2009

HANKE F. D., HANKE W., SCHOLTYSSEK C. & DEHNHARDT G. (2009). Basic mechanisms in pinniped vision. Experimental Brain Research 199(3): 299-311

HANKE F. D., PEICHL L. & DEHNHARDT G. (2009). Retinal ganglion cell topography in harbor seals (Phoca vitulina). Brain Behavior and Evolution 74: 102-109

HANKE F. D. & DEHNHARDT G. (2009). Aerial visual acuity in harbor seals (Phoca vitulina) as a function of ambient luminance. The Journal of Comparative Physiology A 195(7): 643-650

2008

CZECH N. U., KLAUER G., DEHNHARDT G. & SIEMERS B. (2008). Fringe for foraging? Histology of the bristle-like hairs on the tail membrane of the gleaning bats, Myotis natteri. Acta Chiropterologica 10(2): 303-311

HANKE W., BOYLE K. & TRICAS T. C. (2008). Flow measurements during multimodal communication in Hawai'ian Butterfly Fish. Proceedings of the German Association for Laser Anemometry, ISBN 978-3-9805613-4-1, pp 51.3-51.6

MAUCK B., GLÄSER N., SCHLOSSER W. & DEHNHARDT G. (2008). Harbour seals (Phoca vitulina) can steer by the stars. Animal Cognition 11: 715-718

HANKE F. D., KRÖGER R. H. H., SIEBERT U. & DEHNHARDT G. (2008). Multifocal lenses in a monochromat: the harbour seal. The Journal of Experimental Biology 211: 3315-3322

SCHOLTYSSEK, C., KELBER, A. & DEHNHARDT, G. (2008). Brightness discrimination in the harbor seal (Phoca vitulina) Vision Research 48: 96-103

HANKE F. D., HANKE W., HOFFMANN K.-P. & DEHNHARDT G. (2008). Optokinetic nystagmus in harbor seals (Phoca vitulina). Vision Research 48: 304-315

DEHNHARDT G. & MAUCK B. (2008). Mechanoreception in secondarily aquatic vertebrates. In: Senses on the Threshold: Form and Function of the Sense Organs in Secondarily Aquatic Tetrapods, J. G. M. Thewissen and S. Nummela (editors). University of California Press, Berkeley, pp 295-314

DEHNHARDT G. & MAUCK B. (2008). Mechanoreception: Physics and Physiology. In: Senses on the Threshold: Form and Function of the Sense Organs in Secondarily Aquatic Tetrapods, J. G. M. Thewissen and S. Nummela (editors). University of California Press, Berkeley, pp 287-293

2007

BODSON A., MIERSCH L. & DEHNHARDT G. (2007). Underwater localization of pure tones by harbor seals (Phoca vitulina). Journal of the Acoustical Society of America 122 (4): 2263-2269

SCHULTE-PELKUM N., WIESKOTTEN, S., HANKE W., DEHNHARDT G., & MAUCK B. (2007). Tracking of biogenic hydrodynamic trails in harbour seals (Phoca vitulina). The Journal of Experimental Biology 210: 781-787

MAUCK B. & DEHNHARDT G. (2007). Spatial multiple-choice matching in a harbour seal (Phoca vitulina): differential encoding of landscape versus local feature information. Animal Cognition 10(4): 397-405

2006

SIEBERT U., BENKE H., DEHNHARDT G., GILLES A., HANKE W., HONNEF C. G., LUCKE K., LUDWIG S., SCHEIDAT M. & VERFUß U. K. (2006). Harbour Porpoises (Phocoena phocoena): Investigation of Density, Distribution Patterns, Habitat Use and Acoustics in the German North and Baltic Seas. In: J. Köller, J. Köppel & W. Peters (Hrsg.): Offshore Wind Energy - Research on Environmental Impacts. Springer, Berlin, Heidelberg, New York, pp 37-64

HILLE P., DEHNHARDT G. & MAUCK B. (2006). An analysis of visual oddity concept learning in a California sea lion (Zalophus californianus). Learning & Behavior 34(2): 144-153

BODSON A., MIERSCH L., MAUCK B. & DEHNHARDT G. (2006). Underwater auditory localization by a swimming harbor seal (Phoca vitulina). Journal of the Acoustical Society of America 120(3): 1550-1557

HANKE W., RÖMER R. & DEHNHARDT G. (2006). Visual fields and eye movements in a harbor seal (Phoca vitulina). Vision Research 46: 2804-2814

KOWALEWSKY S., DAMBACH M., MAUCK B. & DEHNHARDT G. (2006). High olfactory sensitivity for dimethyl sulphide in harbour seals. Biology Letters 2: 106-109

WEIFFEN M., MÖLLER B., MAUCK B. & DEHNHARDT G. (2006). Effect of water turbidity on the visual acuity of Harbour seals (Phoca vitulina). Vision Research 46: 1777-1783

HANKE F. D., DEHNHARDT G., SCHAEFFEL F. & HANKE W. (2006). Corneal topography, refractive state, and accommodation in harbor seals (Phoca vitulina). Vision Research 46: 837-847

2005

MAUCK B. & DEHNHARDT G. (2005). Identity concept formation during visual multiple-choice matching in a harbor seal (Phoca vitulina). Learning & Behavior 33: 428-436

MAUCK B., BROWN D., SCHLOSSER W. & DEHNHARDT G. (2005). How harbour seals see the night sky. Marine Mammal Science 21: 646-656

KÖHLER C., HOFFMANN K.-P., DEHNHARDT G. & MAUCK B. (2005). Mental rotation and rotational invariance in the Rhesus monkey (Macaca mulatta). Brain Behavior & Evolution 66: 158-166

BURMANN B., MAUCK B. & DEHNHARDT G. (2005). Visual Information Processing in the Lion-TailedMacaque (Macaca silenus): Mental Rotation or Rotational Invariance? Brain, Behaviour & Evolution 65: 168-176

LIEBSCHNER A., HANKE W., SAUERLAND M., MIERSCH L. & DEHNHARDT G. (2005). Sensitivity of a tucuxi (Sotalia fluviatilis guianensis) to airborne sound. Journal of the Acoustical Society of America 117: 436- 441

2003

YAMAN S., VON FERSEN L., DEHNHARDT G. & GÜNTÜRKÜN O. (2003). Visual lateralization in the bottlenose dolphin (Tursiops truncatus): Evidence for a population asymmetry. Behavioural Brain Research 142: 109-114

MAUCK B., BILGMANN K., JONES D. D., EYSEL U. & DEHNHARDT G. (2003). Thermal windows on the trunk of hauled out seals: hot spots for thermoregulatory evaporation? Journal of Experimental Biology 206: 1727-1738

STICH K. P., MAUCK B. & DEHNHARDT G. (2003). Mental Rotation of Perspective Stimuli in a California Sea Lion (Zalophus californianus). Brain, Behavior & Evolution 61: 102-112

DEHNHARDT G., MAUCK B. & HYVÄRINEN H. (2003). The functional significance of the vibrissal system of marine mammals. In: The Merkel Cell: Structure - development - function - and cancerogenesis. K.I. Baumann, I. Moll and Z. Halata. (editors), Springer, pp 127-135

BLECKMANN H., MOGDANS J. & DEHNHARDT G. (2003). Processing of dipole and more complex hydrodynamic stimuli under still- and running water conditions. In: Sensory processing in the aquatic environment. C. S. P. Shoun and N. J. Marshall, Springer, pp 108-121

2001

DEHNHARDT G. (2001). Sensory systems. In: Marine Mammal Biology: An Evolutionary Approach. R. Hoelzel (editor), Blackwell Science, Oxford, pp 116-141

DEHNHARDT G., HANKE W., BLECKMANN H. & MAUCK B. (2001). Hydrodynamic trail-following in Harbour seals (Phoca vitulina). Science 293: 102-104

BLECKMANN H., MOGDANS J. & DEHNHARDT G. (2001). Lateral line research: The importance to use natural stimuli in studies of sensory systems. In: Ecology of Sensing. F. Barth and A. Schmidt (editors), Springer, Berlin, pp 149-167

HILLE P., BECKER-CARUS CH., DÜCKER G. & DEHNHARDT G. (2001). Haptic discrimination of size and texture in squirrel monkeys (Saimiri sciureus). Somatosensory & Motor Research 18: 50-61

2000

STICKEN J. & DEHNHARDT G. (2000). Salinity discrimination in harbour seals: a sensory basis for spatial orientation in the marine environment? Naturwissenschaften 87: 499-502

MAUCK B., EYSEL U. & DEHNHARDT G. (2000). Selective heating of vibrissal follicles in seals (Phoca vitulina) and dolphins (Sotalia fluviatilis guianensis). Journal of Experimental Biology 203: 2125-2131

1999

DEHNHARDT G., HYVÄRINEN H. & PALVIAINEN A. (1999). Structure and innervation of the vibrissal follicle-sinus complex in the Australian water rat, Hydromys chrysogaster. Journal of Comparative Neurology 411: 550-562

BACHTELER D. & DEHNHARDT G. (1999). Active touch performance in the Antillean manatee: evidence for a functional differentiation of facial tactile hairs. Zoology 102: 61-69

1998

DEHNHARDT G., MAUCK B. & BLECKMANN H. (1998). Seal whiskers detect water movements. Nature 394: 235-236 DOI:10.1038/28303

DEHNHARDT G., MAUCK B. & HYVÄRINEN H. (1998). Ambient temperature does not affect the tactile sensitivity of mystacial vibrissae in Harbour seals. Journal of Experimental Biology 201: 3023-3029

SAUERLAND M. & DEHNHARDT G. (1998). Underwater audiogram of a Tucuxi (Sotalia fluviatilis guianensis). Journal of the Acoustical Society of America 103: 1199-1204

1997

DEHNHARDT G., SINDER M. & SACHSER N. (1997). Tactual discrimination of size by means of mystacial vibrissae in Harbour seals: in air versus underwater. Zeitschrift für Säugetierkunde 62 (Suppl. II): 40-43

DEHNHARDT G., FRIESE C. & SACHSER N. (1997). Sensitivity of the trunk of Asian elephants for texture differences of actively touched objects. Zeitschrift für Säugetierkunde 62 (Suppl. II): 37-39

MAUCK B. & DEHNHARDT G. (1997). Mental Rotation in a California sea lion (Zalophus californianus). Journal of Experimental Biology 200: 1309-1316

1996

DEHNHARDT G. & DÜCKER G. (1996). Tactual discrimination of size and shape by a California sea lion (Zalophus californianus). Animal Learning & Behavior 24: 366-374

1995

DEHNHARDT G. & KAMINSKI A. (1995). Sensitivity of the mystacial vibrissae of Harbour seals (Phoca vitulina) for size differences of actively touched objects. Journal of Experimental Biology 198: 2317-2323

1994

DEHNHARDT G. (1994). Tactile size discrimination by a California sea lion (Zalophus californianus) using its mystacial vibrissae. Journal of Comparative Physiology A 175: 791-800

JANIK V. M., DEHNHARDT G. & TODT D. (1994). Signature whistle variations in the bottlenosed dolphin, Tursiops truncatus. Behavioral Ecology and Sociobiology 35: 243-248

1990

DEHNHARDT G. (1990). Preliminary results from psychophysical studies on the tactile sensitivity in marine mammals. In: Sensory Abilities of Cetaceans. J. A. Thomas and R. A. Kastelein (editors), Plenum Press, New York, pp 435-446