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Flashcards in Cetartiodactyla Deck (19)
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Give the number of sub orders and species in this order,

77 species in 2 suborders


Name the 2 suborders of this order

Baleen Whales (10 sp)
Toothed Whales (67 sp)


Give a description of the Mysticeti (Baleen Whale).

Horny plates instead of teeth to filter plankton & invertebrates


Give a description of the Odontoceti (Toothed Whale)

Feed on fish and squid using echolocation


What are the closest living relatives of the Cetartiodactyla ?



When did the 2 characteristic features (echolocation and baleen plates) evolve in their respective suborders ?

After the 2 groups separated ancestrally, Common ancestor did not have both.


Describe briefly the evolutionary history of this order.

Hippo like creatures
Begun to spend time in water
over time lost fore limbs, developed longer tail.
Lost hind legs, tail fluke evolves
2 sub orders separate


Give some of the main adaptions of the blue whales (baleen)

Largest Whale
Streamlined, lost hind limbs
no external ears
Boneless tail fluke


What are baleen plates ?

Filter feeding system which hangs from the upper jaw,
Instead of teeth


How do baleen whales communicate ?

Through production of low frequencies.
Deep ocean channels form under specific temperature, currents & densities.
Channels trap sound and amplify it.


How can you differentiate between baleen and toothed whales ?

Baleen- 2 blowholes
Toothed- Single blowhole


How do baleen whales win females ?

By singing, best vocal ability wins
Are able to teach songs to each other


Give the distinguishing features of the toothed whales head

Jaws extend in beak like snout
Behind snout, the forehead rises in a rounded curve (Melon)


Why has echolocation evolved in 13 species of toothed whales ?

Little light underwater
Sound travels further than in air


Which group of whales, baleen or toothed have more diversity ?

Dolphins, porpoises, narwhales


How is the echolocation produced in Toothed whales ?

Clicks produced via monkey lips in the nasal passages

The melon (waxy, lens shaped) focuses sound at the forehead

Clicks bounce of prey item

Returning sound is channelled through oil filled sinuses in lower jaw to inner ear

inner ear isolated from skull by bubbly foam.


Describe the echolocation of sperm whales

Only produce clicks
Create intense ultrasound which can stun prey


What adaption have some species evolved to counter the echolocation of whales ?

Sensitivity to ultrasound as a means of predation avoidance.


What impact are humans having on marine interspecies communication ?

Production of sound pollution, difficult to communicate effectively.