Guided Notes Marine Mammals
MARINE MAMMALS
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marine mammals
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_________________________________________
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depend on the ocean for its food
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marine mammals evolved to live in the ocean ____________________________
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after mammals originally evolved to live on land
Guided Notes Marine Mammals
EVOLUTION OF MARINE MAMMALS
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________________________________________ 7 separate times
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A prehistoric deermouse is the link between land animals and the whale lineage
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New fossils suggest ________________________________________________
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Breathe air with ___________________________________________________
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Have hair
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Live birth
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Mothers feed young milk
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________________________________- regulate body heat with their metabolism
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4 chambered heart
SOME ADAPTATIONS TO A LIFE IN WATER
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Blubber and thick coats of hair to ____________________________________
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Tetrapod limbs modified into _______________________________________
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Swim by moving up and down
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Caudal tail is oriented horizontally
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Bodies modified for swimming: _____________________________________
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Collapsible lungs and rib cages for deep diving
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Ability to _______________________________extremities to increase dive time
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Record-1 1/2 hour long, 6000 ft deep dives ex.-___________________________
CLASSIFICATIONS
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Order- __________________________________
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Family Mysticeti
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Family Odontoceti
Guided Notes Marine Mammals
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Order __________________________________
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Suborder Pinnepedia
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Family Phocidae
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Family Otariidae
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Family Odobenidae
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Family Mustelidea
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Family Ursidae
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Order __________________________________
Order Cetacea
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80 different species, _______________________________________
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Intelligent social animals
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Two groups of whales
Suborder Mysteceti- ___________________________________________
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_________________________that eat plankton and small fish
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Blue, finback, humpback, right and gray whales
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To feed- open mouths and take in enormous quantities of water and filter
out food
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Rorqual whales have _____________________to help collect more water
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Baleen- _____________________________________________________
Baleen Feeding Methods
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________________- take in huge gulps of water to eat krill and small fish
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_______________ -swim through near surface waters to skim and strain plankton
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______________ - bottom feeders that suck up sediments to filter out small
crustacean and other invertebrates
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_________________ -____________________________________________
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Swim up thru middle of the bubbles and gulp prey
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May involve cooperative hunting
Guided Notes Marine Mammals
Order Odontoceti ____________________________________
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Peglike teeth to catch fish, seals, penguins and squid
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Sperm, killer, pilot, beluga, dolphins and porpoises
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__________________________with specialized teeth who swallow their
prey whole
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Male narwhal tooth grows out of it’s upper jaw
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Used to attract mates and _________________________
Whale Reproduction
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Fertilization and development are __________________________________
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Gestation lasts 11 to 18 months
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Breeding once every three years
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_______________________________________________________________
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Newborns are brought to the surface for their first breath
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Nursed for 6 to 10 months
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Milk is 50% fat so the calves can grow quickly
Whale Adaptations and Behavior
Breathing
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Breathing thru the ________________________(nostril)
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Thru whale evolution nostril moved from the snout to the top of the head
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Air moves from ___________________________________________
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________________________________________________________
Swimming
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_______________________________________________________
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Dorsal fin is used in _______________________________________
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Pectoral fins are used in ____________________________________
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Bone structure is similar to the bones in hand
Guided Notes Marine Mammals
Other Movements
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_______________- smashing tail down on the surface of water (maybe displaying
aggression)
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_______________- head is raised above water surface for a period of time
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_______________- leaps out of water and crashes back down
Migration
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Whales travel 1000’s of km a year with their______________________________
_________________________________________________________________
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Navigate using geologic features, ocean currents, water chemistry, magnetic field,
and sun
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Migrate between ________________________________________
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Summer-feeding in rich Arctic waters
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Winter- Breed in warm, shallow and secluded tropical waters
Keeping Warm
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__________________________________________________________
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Sperm whale may dive to depths of 3000m
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Migrate to cold Arctic waters
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Posses thick layer of ____________________________________________
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Traps and prevents heat loss
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Can be 2 feet thick
Communication
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_________________________________________________________________
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Complex types of communication have been documented
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Used in _____________________________________________________
____________________________________________________________
Guided Notes Marine Mammals
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Echolocation-
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Humpback whales compose complex songs which differ by individual and pod
Order Carnivora
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Suborder Pinnepedia
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Family Phocidae: True seals
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____________________________________________________________
____________________________________________________________
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Family Odobenidae: ___________________________________________
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two long tusks, no external ears, but can rotate their hind flippers and
"walk" on land
Seals and Sea Lions and walruses…
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Pad-like appendages and torpedo shaped bodies
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Seals and sea lions are
_________________________________________________
Pinniped Reproduction
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Return to land to mate and give birth
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Breeding season results in congregates of 1000’s
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Males usually compete for harems of females with whom they mate
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___________________________________________________________
___________________________________________________________
Pinniped Adaptations
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_____________________________________ who also use communication
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Deep divers- elephant seal dives up to 1500m
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Thick layer of blubber insulation
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Thick fur
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Walruses have tusks for __________________________________________
Guided Notes Marine Mammals
Family Mustelidea _____________________________________
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Only recently adapted to aquatic life (3mya)
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Sleep, eat, mate and rear young in ocean
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Smallest mar mamm found only in Pacific
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_____________________________________________________
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Feed on species that would otherwise destroy the kelp (sea urchins and
snails)
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Dive for shellfish, at surface use a rock to get to their food
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________________________________________________ (1000 hairs per inch)
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________________________________________________________________
Threats to Sea Otters
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Oil spills- _____________________________________________
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Past hunting for their prized fur decimated otter populations almost to extinction
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Otters freeze because of the loss in insulation
________________________________________________
Predation-killer whales and sharks
Family Ursidae: Polar bears
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Most terrestrial ____________________________________
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Lives on ice floes of the north polar region
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__________________________________________________________________
__________________________________________________________________
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Not an excellent swimmer
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Hunt seals sunning on ice or coming up thru ice holes to breathe
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__________________________________________________________________
Guided Notes Marine Mammals
Order Sirenia- Dugongs and Manatees
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live in warm or tropical waters
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________________________________________________________________
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Shy, social animals thaft communicate via squeaks
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________________________________________________________________
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the Steller sea cow, once inhabited Arctic waters, but was hunted to extinction by
1768, within 27 years of its discovery
Threats to Manatees
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________________________________________________________________
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Frequently injured or killed by powerboat propellers
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________________________________________________________________
Guided Notes Marine Mammals
MAMMAL CHARACTERISTICS