Exam 1

Question 1

What is a marine mammal?

Answer 1

Mammal bound to marine habitat.
Viviparous
Lactation/mammary glands
Hair/fur

Question 2

Define viviparous

Answer 2

It means “live births”

Question 3

What are the Orders of Cetaceans?

Answer 3

Odontocetes

Mystecetes

Question 4

Order Odontoceti characteristics

Answer 4

Toothed whales (includes dolphins)
One blow-hole

Question 5

Order Mysticeti

Answer 5

Baleen whales

Two blow-holes

Question 6

Order Sirenia

Answer 6

Manatees and dugongs

Question 7

What are the sub-order names for Manatees and dugongs?

Answer 7

Manatees: Trichechidae
Dugong: Dugongidae

Question 8

If Pinniped is a sub-order, what is its Order name?

Answer 8

Carnivora

Question 9

What are the families of Pinnipeds?

Answer 9

Phocidae
Otaaridae
Odobenidae

Question 10

What are Phocides?

Answer 10

True Seals

Question 11

What are Otaarids?

Answer 11

Sea lions and Fur seals

Question 12

What are Odobenids?

Answer 12

Walrus

Question 13

Other Carnivora families and what are the animals?

Answer 13

Mustellidae: Sea Otters
Ursidae: Bears

Question 14

What was the cause of marine mammal evolution?

Answer 14

1. Lack of terrestrial resources (No space, no food)
2. Predators on land
3. Swimming
4. Sea Level
5. More food in the aquatic environment

Question 15

How many million years ago was the cretaceous/tertiary extinction? (End of the dinosaurs)

Answer 15

65 Mya

Question 16

When did the first cetacean fossil show up? where was it found? and what was the name of the animal?

Answer 16

54 mya, in Pakistan, and named Pakicetus

Question 17

When did the first sirenian fossil show up? and where?

Answer 17

50 mya in Egypt/Italy

Question 18

Why were there also fossils of sirenians and cetaceans found in Jamaica and South Carolina?

Answer 18

They migrated because the tethys sea was closing up.

Question 19

What animal arrived about 30 mya? Where? and what present day animal did they resemble?

Answer 19

Desmostylians showed up in the North Pacific and looked like a modern day Hippo.

Question 20

What animals started to show up about 27 mya? and where?

Answer 20

Pinnipeds in the North Pacific

Question 21

What happened major event happened about 30 mya and explain it?

Answer 21

The circumpolar current and polar ice caps are established from Antarctica splitting away from South America.
Cold water circulation sinks and develops deep water currents, which leads to coastal upwelling which produces an abundance of nutrients.

Question 22

What showed up about 15 mya?

Answer 22

Bears

Question 23

What showed up about 5 mya?

Answer 23

Aquatic Sloth

Question 24

What showed up about 1-3 mya?

Answer 24

Modern sea otters

Question 25

When did polar bears show up?

Answer 25

Roughly 300,000 years ago.

Question 26

What are the subfamilies of the family Otariidae? and which animal are they? and where do they specifically live?

Answer 26

1. Otaarinae: Sea Lions 2. Arctocephalinae: Fur Seals Only in the Pacific in the northern hemisphere

Question 27

What is the closest outgroup of Cetaceans?

Answer 27

Ungulates (Cows, etc.) (Even-toed, hoofed animals)

Question 28

What cetacean characteristics did Pakicetus have?

Answer 28

Cetacean ear | Amphibious predator but more terrestrial.

Question 29

What evolved from Pakicetus? And what did they look like?

Answer 29

48 mya- Ambuloretus - "Crocodilian" 48 mya- Protocetidae - more aquatic - started dorsal kicking 40-34 mya- Basilosauridae - Looks like a whale but still has tiny hind legs 40-34 mya- Dorudontidae - Direct ancestor of modern odontecetes

Question 30

Physical adaptations from Pakicetus to Dorudontidaes (54-34 mya)

Answer 30

Reduction in hind legs, pelvic girdle Blowhole moving back (about half-way back on head) Flexible elbow Heterodont teeth

Question 31

Differences between Mysticetes and Odontocetes

Answer 31

Mysticetes: Teeth, symmetrical craniums, 2 blow-holes, more floating ribs, telescoping of skulls differ. Odontocetes: Baleen, 1 blow-hole, Asymmetrical cranium, large breastplate/ribs

Question 32

Types of Cetacean distribution

Answer 32

Cosmopolitan Anti-Tropical Circumpolar Pantropical

Question 33

Pachyostotic bones

Answer 33

Solid bone throughout the manatee body that does NOT have bone marrow.

Question 34

3 species of the family trichechidae

Answer 34

West Indian Amazonian West African

Question 35

Around what time did Polar bears split from Grizzly bears?

Answer 35

343,000-479,000 years ago

Question 36

Adaptations mammals had to make to become a marine mammal.

Answer 36

``` Propulsion/locomotion Thermoregulation Diving/breath-holding Communication Osmoregulation Sensory biology ```

Question 37

Seawater is ______ more dense than air

Answer 37

800 times

Question 38

Modes of propulsion

Answer 38

Drag-based (paddling) -- Max 50% efficient | Lift-based (Hydrofoils)-- Up to 80% efficient

Question 39

Hydrodynamic Adaptations

Answer 39

Maximize Laminar flow - Parallel boundary layer flow - More hydrodynamic critters have a higher "critical velocity" Decrease drag - Frictional or viscous drag - Pressure drag

Question 40

How do you measure hydrodynamic efficiency?

Answer 40

Fineness Ratio and Reynolds number

Question 41

Fineness Ratio equation and what value is the most ideal?

Answer 41

Length/max diameter | 4.5 is ideal

Question 42

Reynold's number

Answer 42

R=(Body length x Swim velocity)/[(Water viscosity)/(water density)] The lower the R value means the more hydrodynamic it is.

Question 43

Balaenidae

Answer 43

Right Whales (only 2 species exists)

Question 44

Eschrichtiidae

Answer 44

Gray Whales (Only 1 species left)

Question 45

Balaenopteridae

Answer 45

Rorqual whales

Question 46

Physeteridae

Answer 46

Sperm whale (Only 1 species left)

Question 47

Kogiidae

Answer 47

Pygmy/dwarf sperm whales

Question 48

Ziphiidae

Answer 48

Beaked whales

Question 49

Monodontidae

Answer 49

Belugas and narwhals

Question 50

Delphinidae

Answer 50

Dolphin

Question 51

Phocoenidae

Answer 51

Porpoises

Question 52

Trichechidae

Answer 52

Manatees

Question 53

Dugongidae

Answer 53

Dugongs