Aquatic Mammals Flashcards Preview

Biology Of Mammals > Aquatic Mammals > Flashcards

Flashcards in Aquatic Mammals Deck (50):
1

Which 3 orders contain aquatic mammals?

Cetacean, Carnivora, Sirenia

2

Which Canivore families have aquatic mammals?

Pinnipedia, Ursiade, Musteliade

3

What are the 2 groups of cetacea?

Mysticetin, Odontoceti

4

What feeding adaptation do mysticetin's have?

Baleen - filter feeding

5

Which 4 families are within mysticetin?

Balaenidae, Neobalaenidae, Balaenopteridae, Eschrichtiidae

6

What is the odontoceti skull like?

Asymmetrical

7

Which families are in odontoceti?

Delphinidae, Monodontidae, Phocoenidae, Physeteridae, Plantanistidae, Iniidae, Ziphiidae

8

Which families are in pinnipedia?

Otariidae, Phocidae, Odobenidae

9

Which species are in otariidae?

Sea lions and fur seals

10

What are the features of otariidae?

External ears, better on land, hind flipper for land locomotion, enlarged forelflipper

11

What are the features of phocidae?

No external ears, more marine adapted, smaller flippers

12

Which animals are in phocidae?

Seals, elephant seals.

13

Which animals are in odobenidae?

Walrus

14

What is a dugong tail like?

Tail fluke - notched

15

Which animals are in Trichechidae?

Manatees

16

What is a manatee tail like?

Spatulate

17

What are the features of cetacea reproduction?

Mating at sea, testes abdominal, penis retractable

18

What are the features of pinnipidia reproduction?

Harem

19

What is gestation of aquatic mammals like?

Extended but not relative to size

20

What is a blue whales gestation like?

Rapid development, extended parental care

21

Where does birth in cetacea take place?

At sea

22

Where does birth in pinnipeds take place?

On land

23

Where does lactation in cetacea occur?

Teats in slits near urogential opening

24

What is aquatic mammal milk like?

Highly concentrated

25

How are aquatic mammals insulated?

Subcutaneous fat layer, fur

26

How does the countercurrent exchange work?

Conserves heat in core, flippers insulated.

27

Why are sirenia less adapted?

Less body fat, not good at retaining heat. Live in warmer waters

28

How do marine mammals cope with the hyperosmotic environment?

Metabolic water, concentrated kidneys

29

How much more myoglobin do marine mammals have?

2-9 x more

30

What happens to breathing during deep diving?

Extended apnoea, lack of breathing.

31

How do baleen whales feed?

Keratinous plates

32

How does lung feeding occur?

Rorquals, throat furrows

33

How does the mammal withstand the force of water during lunge feeding?

Mandible fraced by frontomandibular

34

What are bubble clouds?

Groups of humpback whales encircle fish, lung feed

35

How does sucking and dredging occur?

Plough head through mud, coop and suck up sediment

36

What is carnivore dentition like?

Sharp canines, simple cheek teeth

37

How are walrus' adapted to feeding?

Bentic invertebrates, suck out, discard shells

38

How are walrus flippers adapted?

Right handed lateralised limb used to root through sediment

39

How are sea otters keystone species?

Otters harvest the increased urchins to prevent loss of kelp beds

40

How do sperm whales locate?

Echolocation

41

How do sirenia feed?

Slow moving grazers, herbivorous

42

What is the function of fusiform body?

Reduce drag and turbulence

43

How are lungs adapted for deep sea diving?

Small and elastic

44

What adaptations do deep sea diving mammals in their respiratory tract?

Rigid cartilaginous airways, flexible ribs, elastic bronchioles

45

How do sirenia control buoyancy?

Dense, heavy bones. Fermentation gas

46

How is echolocation produced?

Clicks with air forced through valves in nasal sac

47

How is echolocation focused?

Through melon lens

48

Whys vocalisation more important?

High conductance of sound in water

49

How do mysitcetes create sound?

Larynx, vocal folds.

50

What is rete mirabile?

Network of blood capillaries between swimming muscles which act as heat exchanger