L6 - Marine Mammals 1

Question 1

Since all marine mammals are endothermic, what 3 general adaptations have occurred?

Answer 1

1) increased insulation

2) Circularity adaptions
- counter current heat exchangers
- physiological adaptations
- O2 stores

3) osmoregulation adaptations

Question 2

What are the 3 families of Pinnipeds?

Answer 2

1) Otariidae - sea lions and fur seals
2) Odobenidae - walruses

3) Phocidae - true or earless seals
- sub families - Monachini and Phoca

Question 3

What are the fore and hind limbs of otariid seals like compared to phocid seals?

Answer 3

Otariid

• forelimbs are modified for locomotion
• hind limbs are for steering and can be turned forwards

Phocid

• forelimbs are reduced
• hind limbs held together and moved side to side - shuffle on land

Question 4

Describe the spine, ears and skin of each:

a) Otariid
b) Phocid

Answer 4

a) Otariid
spine - long thoracic spines
ears - external pinna
skin - fur

b) Phocid
spine - transverse spines of lumbar vertebrae are developed
ears - no external pinna
skin - blubber

Question 5

In the Infra order Cetacea there are 2 parv-orders, what are they?

Answer 5

1) Odontoceti - toothed whales
e. g.: dolphins, narwhals

2) Mysticeti - baleen whales

Question 6

Give 5 example animals in Odontoceti

Answer 6

• Dolphins
• Sperm whales
• Killer whales
• beaked whales
• Narwhals

Question 7

Give 5 example animals in Mysticeti

Answer 7

• right whales
• pigmy right whales
• grey whales
• humpback whales
• blue whales

Question 8

How do Mysticeti whales feed?

Answer 8

Filter feeding, grazing, and bubble cloud feeding

Question 9

How do Odontoceti whales feed?

Answer 9

Hunting and suction