1. Sensory Perception Vision Olfaction Hearing & mechanoreception Electroreception Magnetoreception

2. Senses Physical QuantitySense Organ SoundEars Water flowLateral line ChemicalsTaste Buds/Nose ElectricityAmpullae of Lorenzini Magnetic FieldsNose ???? LightEyes

3. Acoustico – Lateralis System Hair sensory cells Equilibrium Hearing Mechanoreception

4. Sensory Hair Cells

5. Hearing in Fishes Fish have ears Otoliths detect particle motion Swimbladder can act as pressure transducer

6. What is Sound? Sound is a mechanical vibration that propagates through an elastic medium such as air or water. Sound travels as waves of oscillating particles accompanied by increases and decreases in the ambient pressure. Sound propagates along the axis of particle vibration.

7. Ear Morphology

8. Fish hearing is generally low- frequency

10. Cyprinidae

11. American Shad Audiogram

12. Ultrasonic detection by american shad. Classical Conditioning: Example of cardiac response followed by electric shock

13. Ultrasonic sound detection by American Shad Auditory Brain Response

14. Swimbladder of the toadfish, Opsanus sp. Sonic muscles can be seen on the lateral walls. Batrachoididae Oyster toadfish Opsanus tau Sound Production

15. Ecology of Sound Production Sound produced by spawning aggregation of sciaenids

16. Lateral Line Neuromasts: groups of hair cell w/gelatinous cupule

17. Hydrodynamic Stimuli Water currents from flows (rheotaxis) Schooling/predator avoidance Active hydrodynamic imaging Passive hydrodynamic imaging Courtship Subsurface feeding

18. Flows produced by organisms

19. Lateral line shapes

20. Electroreception Elasmobranchs Teleosts Low frecuency AC - DC Teleosts High frequency AC

21. Electroreceptors

22. Ampullae de Lorenzini Dogfish can detect a flounder buried 15 cm deep (1 mV/Km)

25. Electrical fishes

26. Electric Organ Discharge (EOD) Modified muscle cells to create EOD

27. Brachyhypopomus spp. EOD

28. Magnetoreception Elasmobranchs –Hammerhead shark schools –Laboratory experiments with rays Teleosts –Magnetite found in Salmon and Tuna

29. Magnetoreception

30. Induced Electric Field Currents in ocean flowing through earth’s magnetic field generate currents from <5 nV/cm to 500 nV/cm. Suspected that eels use these currents, but not clear if they are sensitive enough to electrical fields. Stingrays can sense fields as low as 5 nV.cm

31. At ambient magnetic field of 0.5 gauss, a swimming speed of 1 cm/s would produce a threshold stimulus of 5 nV/cm. This has yet to be proven.

32. Magnetite in Nose (Trout) a.Bacteria containing magnetite (not from the trout). b.Olfactory epithelium. Red dot with arrow is putative magnetite. c.Bright field (left) and dark field (right) TEM of dot from b. d.Energy dispersive analysis of x-rays from crystal. Shows presence of iron (Cu is from copper screen, Pb and U from TEM stains). Walker, Diebel, Haugh, Pankhurst, Montgomery, & Green. 1997. Structure and function of the vertebrate magnetic sense. Nature. 390: 371-376.

33. Olfaction

36. Taste Buds

37. Vision

38. Photoreceptor cells Rods –Sensitive at low light levels –Present in all fishes Cones –Sensitive at high light intensity –Some elasmobranchs and most fishes Red cones (600nm) Green cones (530nm) Blue cones (460nm) Ultraviolet cones (380nm)

39. Electromagnetic Wavelengths

41. Rod maximum absorption

42. Visual Acuity Determined by eye aperture and photoreceptor density. Acuity increases as size increases.