Flashcards in Cetartiodactyla Deck (19)
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)
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.