Toni Christopher Marine Mammals Dr. Jerry Skinner

 The study of animal sounds, their meanings, and their purpose  Two categories of them  Terrestrial or airborne  Underwater or Marine  Three sub-categories  Hearing ability and mechanisms  Sounds and how they’re made  Function and meaning of specific sounds

AIRBORNEUNDERWATER  Medium: air  Shorter range sounds  Higher frequency  Medium: water  Longer range sounds  Lower frequency  Sounds heard faster and clearer  Water conducts sounds better  Already matches density of inner ear where sound is processed

 Other senses are dulled by the water  Water absorbs and reflects light, making sight very limited  Smell can’t be relied upon because molecules take so long to diffuse in water

 Long, low frequency songs  A single high frequency click or whistle  Rapid bursts of high frequency clicks or whistles

 Echolocation, or locating by means of reflected sonar signals  Not observed in baleen whales  Communication within the group  Navigation  Detection of both predators and prey  Courtship rituals

 Air passes through structure in nasal cavity called phonic lips  Membranes collide and vibrate surrounding tissue  Vibrations pass through head tissue while air enters vestibular sac  Air either reused or sent through blowhole  All toothed whales except Sperm Whale have two sets of phonic lips; one set per independent sound

Thank you Dr. Skinner!

 Do not have phonic lips  Larynx may be used but no vocal cords  Don’t need to exhale to produce sounds  Recycled air or cranial sinuses may be used

 Base units (“notes”) – single sounds up to a few seconds long  May change pitch to higher or lower and/or amplitude to louder or quieter  Sub-phrases – four or six units, ten seconds at most  Phrases – two sub-phrases  Themes – phrases repeated over for two to four minutes  Songs – group of themes about 30 min long  Repeated for either hours or days

 Defining territory to other whales  Sexual selection during mating season  Multiple males competing over same mate  “flirting”  Singing reported in groups of one female and many males  Also reported when a male is following a female around, acting as an “escort”  Echolocation

Toni Christopher Marine Mammals Dr. Jerry Skinner