1. Echolocation -using sound waves & echoes for orientation and hunting Information on: size, shape, distance, movement, texture, & sometimes internal structure (but not color) echo has altered sound qualities -sound emitted

2. microchiropterans -toothed whales Echolocation -using sound waves & echoes orientation hunting

3. Allen’s big-eared bat, Idionycteris phyllotis AZ Chiracahua Mtns, June 2004 For most of history, how bats oriented in the dark remained a mystery.

4. Rousettus spp. Old World fruit bat (Megachiroptera) -utters a high-pitched series of tongue clicks -simple echolocation mechanism

5. Oilbirds: Steatornis

6. Advantages of Echolocation Detect size, shape, distance for hunting and orientation. Ability to roost away from vision-orienting predators. Opens up an enormous feeding niche. Insects flying at night are nearly invisible to vision-oriented predators. Most prey cannot hear you. Advantages of Echolocation Detect size, shape, distance for hunting and orientation. Ability to roost away from vision-orienting predators. Opens up an enormous feeding niche. Insects flying at night are nearly invisible to vision-oriented predators. Most prey cannot hear you. Disadvantages? Conspicuous. Calling all the time announces your presence. (But a benefit to biologists.) Radar-detector syndrome: Information leakage - some insects have co-evolved ways to detect bat calls. Disadvantages? Conspicuous. Calling all the time announces your presence. (But a benefit to biologists.) Radar-detector syndrome: Information leakage - some insects have co-evolved ways to detect bat calls.

7. Properties of Sound -sound manifested as vibrations in a medium -These vibrations take the form of waves -Can measure sound in a number of ways

8. Frequency-number of cycles per second (pitch) short wavelength = high frequency Wavelength-distance from peak to peak in a sound wave Amplitude-height of the soundwave (loudness)

9. The nature of sound = ƒ velocity = wavelength frequency Velocity, essentially constant (speed of sound, ~300 m/s)... gets smaller as ƒ gets higher

10. The operational frequency influences the interaction of the wave with targets. The nature of sound A target must have a dimension > /2 to generate an echo.

11. The nature of sound Bats that use lower frequencies are constrained to larger targets. 100 1.5 gnat 50 3.0 fly 20 7.5 moth 10 15.0 kHz ~smallest target (mm )

12. The nature of sound Pro: greater detail Con: attenuate more quickly, i.e., less range Higher frequencies Pro: travel farther in atmosphere, i.e., greater range Con: less detail, blind to small targets Lower frequencies

13. Bats use high frequency sounds in echolocation BODY SIZE SIZE OF PREY bats eat small insects less noise can produce sounds with short wavelengths FADE FAST small sound production apparatus Frequency of 50 KHz = Wavelength of ~7mm

14. Sound Emission in Bats Most bat echolocations are extremely loud (110 decibels) Tensor tympani- tenses eardrum Tensor stapedium- tenses stapes Auditory bullae- floating in cartilage Emit sounds through mouth or nose Eptesicus

15. Rhinolophus -can detect relative movements of 0.1 m/s

16. Doppler Effect CF also very good for detecting movement

17. -Searching -Movement (doppler shift) -Not much detail on target -Approach & capture phase -Highly detailed info on target Echoes from many different sizes of objects Range of frequencies = Range of wavelengths

18. Bats use a variety of CF and FM calls CF-searching FM-approach Terminal buzz 3-phase cycle repeated over & over CF FM- buzz

19. search phase approach phase terminal phase “buzz”

20. As bat approaches a moth... 2. Sound wedge reaches moth 1. Bat emits sound pulse (FM in approach phase)

21. As bat approaches a moth... 3. Some echoes return from the moth 4. Some of the sound waves travels on

22. As bat approaches a moth... 5. Background objects return echoes too In cluttered environments it is advantageous to have calls that fade fast (attenuate) Higher Frequency (can be CF or FM)

23. Habitat partitioning by bats Background noise not a problem

24. Gleaners Open-air insectivores large ears, fly slowly short, thick wings small ears, fly fast long, skinny wings Use long CF or Steep FM pulses of High Frequency -detect movement, minimize noise Use low frequency FM pulses -maximize range

25. Many gleaners also use passive hearing to detect prey Striped hairy-nose bat Mimon crenulatum

26. Lasiurus borealis shorter, higher frequency What about noise from other bats? -change frequency, shorten calls, increase duration between calls Bats can personalize calls

27. Rhinolophus Many insectivorous bats use wings to scoop up insects

28. Geoffroy’s bat Myotis emarginatus

29. In nasal-emitting bats the rostrum is rotated down nasal area aligned with direction of flight keep mouth closed Most bats are oral-emitters fly with mouth open most fast flying aerial insectivores highly varied diet

30. Tent-building bat Uroderma bilobatum

31. Greater horseshoe bat Rhinolophus 3-part nose-leaf

32. Flower-faced bat Anthops ornatus

33. Orange leaf-nose bat Rhinonycteris

34. Great Himalyan leaf-nose bat Hipposideros

35. White bat Ectophylla alba Another tent builder

36. Ghost bat Macroderma gigas Carnivorous bats mouse-eater

37. Fringed-lipped bat Trachops cirrhosus Carnivorous bats

38. Fringed-lipped bat Trachops cirrhosus Carnivorous bats

39. Dammit Jules, isn’t there anything we can do!

40. Some insects can hear bats & take evasive action SIMPLE EAR (Tymbals) -often on each side of thorax Some moths can “jam” bat’s echolocation system -produce high-frequency clicks from tymbal organs -In Sphingids on the palps

41. In days of old and insects bold (Before bats were invented), No sonar cries disturbed the skies- Moths flew uninstrumented.

42. The Eocene brought mammals mean And bats began to sing; Their food they found by ultrasound And chased it on the wing.

43. Now deafness was unsafe because The loud high-pitched vibration Came in advance and gave a chance To beat echolocation.

44. Some found a place on wings of lace To make an ear in haste; Some thought it best upon the chest And some below the waist.

45. Then Roeder's key upon the breeze Made Sphingids show their paces. He found the ear by which they hear In palps upon their faces. Of all unlikely places!

46. Echolocation in Cetaceans -How is it the same, how is it different from bat echolocation?

47. Bats use high frequency sounds Cetaceans use lower frequency sounds -size of prey -size of sound producing equipment -clutter -density of water vs. air

48. -auditory bullae loosely attached to dentary (not skull) -greatly improves directionality Sound produced in nasal air sacs

49. Dolphin’s use a series of broad-band clicks increases in frequency Also have feeding buzz

50. Sperm whale

51. “Monkey Lips” -pop and increase the complexity of outgoing sound

52. Echolocation Summary Advanced echolocation only in Microchiropterans and Cetaceans Bats have a great variety of echolocation equipment & types of calls -exploit many environmental & microhabitat niches Cetaceans focus outgoing sound through melon and receive echoes through oil channel in lower jaw Same basic principle in bats and cetaceans, but apparatus is different

55. North American members of Mustela