Flashcards in Cetacean Sociality Deck (51):
Why are cetaceans so social? (broad view
-don't have "home ground" => only each other
What is the idea behind cooperative defense?
Predation: 1 Shark: 1 dolphin, shark wins
1 Shark: Multi-dolphins, dolphins win
Give some examples of cooperative defense.
1. Spinner dolphins in Hawaii under threat: tightly cluster, juveniles in the center
2. Flower formation in Sperm Whales: heads toward young, powerful tails toward predators
Mysticetes are ______ (not as/are as/more) clever than odontocetes.
What are examples of coalitional behavior in bottlenose dolphins?
trio of males have prolonged, close association => trio herds female to prevent other males from getting access
Within cetaceans, what group exhibits coalitional behavior?
long term friendly, similarly aged males
What are "second-order" alliances?
groups of trios--work together to fend off other coalitions, even tho the only one coalition in this "super coalition" ends up with access to the female
What are "super alliances"?
alliances that join with others to compete against others
What are the benefits of cooperative hunting?
cooperation enables school to control/access resources (fish school) that one animal alone could not
What are examples of cooperative hunting?
1. bottlenose dolphins: co-op herd fish school to surface, take turns eating; co-op to drive fish on shore
2. orca co-find and herd fish; transient orca work together to take other whales
3. humpback whales create bubble nets to surround large schools of fish (only mysticete that feed cooperatively)
(true/false): when groups of trios work together to fend off other coalitions, they all get a turn with the female
False; only one coalition in the "super coalition" ends up with access to the female
do spotted dolphins have fixed coalitions like the bottle nose dolphins?
no. coalitions not as fixed but they have preferred associates who often work together in social and feeding situations
Why is there no less help in primates wth collaborative foraging?
different ecology; don't really need help eating a leaf
What is the effect of ecological constraints on cetaceans?
-affect and influence many behaviors
-setting constrains practices
What are the effects of ecological constraints on residential, coastal pods of orcas vs. smaller, transient orca pods?
resident, coastal pod = extended family units, work together to take fish, more noisy
transient=better for driving/capturing seals onshore; unite to get whales; silent when hunt (acoustically sensitive) marine mammals
What are the differences in behavior between coastal dolphin species (bottlenose) vs. pelagic (deep water) dolphins (spinner)?
coastal = more aggressive, can find each other again after fight
pelagic = must get along, if separate from group, survival threatened (parallel is polite)
What social structure do orcas have?
matriarchal, family groups
What is the importance of synchrony?
-provides and conveys unity
-males use to impress girls and guys i.e. tandem novelty, synchronize calls
When and how do dolphins develop synchrony skill?
-develop at birth
-infants "slipstream" besides mom to save energy
What are the synchronous vocalizations and actions an example of?
fission fusion, split up and go back together
How are dolphin's gestural and facial repertoire limited?
through their hydrodynamic (reduced turbulence) design and minimal articulation
BUT still do some gestural/postural communication
How do dolphins show threat?
display teeth, make body appear larger via "S posture"
How do dolphins show solicitation?
body tilt, show bright underside, give access to genitals
How do dolphins' bodies make use of camouflage?
most species dark above, light below, camouflaged from below against sky, from above depths
-tilting taps for high contrast, motion
How are dolphins' eyes an example of how they communicate?
eyes often high contrast to body, so noticeable, likely to be signals especially at close range
What is "disruptive coloring"?
-cetaceans eyes can be osscured espeically in top predators or prey
-i.e. orca and Commersons
Describe dolphins' tactile sense.
-high tactile sensitivity => affiliative behavior often involves contact
What are some examples of how dolphins use contact in affiliative behavior?
-rub, pet, "whet pecs" >> like grooming in primates, calming, bonding, builds trust
-sex = often involves prolonged forelplay of rubbing, caressing, buzzing
(True/False): Dolphins' sex is always reproductive.
False; different age and gender combinations; sex = social behavior
When would smaller spotted dolphins win against larger bottlenose dolphins?
-spotted can "win" when they show postural dolphins and vocal synchrony
What are the odontocetes' three classes of vocalizations?
3. burst pulses
What is a whistle from odontocetes?
social; narrow-band (usually 1 freq at a time) frequency modulated
What is an example of whistles in odontocetes?
spinner dolphins chorus whistles to rally whole school, resting in bay, to go hunt together
Why are older dolphins typically better at synchronizing calls?
What are clicks?
for echolocation: wide band (e.g. 5-150 KHz), ultra brief, in "trains" w/gaps for returning echoes
What are some social functions of clicks?
-"eavesdrop" on one another's echoes?
-detect echolocation as indication that others are feeding
-genital or fetus inspection
How are clicks associated with tacto-acoustics?
-include tickle buzz, caress, punch
-can be used to affect other dolphins
What are burst pulses?
Social: highly variable, produced by dorsal Bursae like clicks, but with freq and amp modulation
-include high arousal vocalizations (screams, growlsm etc.) but some more "conversational"
What else do cetaceans use for vocal/auditory communication besides whistles, clicks, and burst pulses?
How do cetaceans use percussives?
breach, pec slap, tail slap, etc. against surface of water >> loud, visible splash
What does using percussives communicate for cetaceans?
provide info on location, size, arousal state, attitude, etc.
Give a specific example of how cetaceans use percussion.
spinner dolphin "spin" makes distinctive percussion, indicate very high arousal
Explain how mysticetes "sing"
-Some bowhead whales are simple, few tone, repeated songs
-humback whale song-each male repeats 20+ min song with several phases
What are the characteristics of the humpback whale song?
-sung (only?) on breeding grounds, attracts females/repels (spaces out) males
-All males in region start season with same son, all maintain same changes in song throughout season, no singing in off season but all resume same song where left off
-changeds usually = gradual modification of existing song
give an example of cultural transmission through humback whale song.
sudden appearance of E Austrailia song in W Austr shifted whole W pop to E song by 3rd season
Why do odontocetes need "signature calls"?
changing water depth affects pressure in vocal anatomy, may alter voice
How do dolphins use individual specific signature whistles?
-announce self, occassionally made by others in group
-male coalitions eventually develop a "coalition whistle" that replaces individual signature
In what social interactions do dolphins use signature whistles?
-made by animals forcibly isolated from group--can get troup members matching call
-may serve as reunion calls in mother/infant or other Fission/Fusion situations
What are orca dialect calls?
burst pulse sounds specific to coalition, family, pod, kin group (Even across pods), community, etc
What purpose do Orca dialect calls serve?
-same function as dolphins' signature whistles but not individual specific
-orcan from different oceans housed together, learn some of each other's calls and develop a "tanked" call