Final Test

Question 1

Explain how the size of an animal is related to metabolism?

Answer 1

As an animal becomes larger the surface area increases as the square of the base dimension. Where as the volume increases as the cube of the base dimension.

As an animal gets bigger the volume will growing faster than the surface area will because the volume is growing at the rate of cubed, where as the surface area is growing at the rate squared.

Big animals have a lot of volume to relatively less surface area - surface area to volume ratio or scale effect

Small animals like shrews have 6 times the surface area to their insides. They are endothermic they’re generating heat from their metabolism. But they have 6 times the surface area compared to their interal volume which means they are bleeding off that heat really fast and need to male more heat by eating more. This is why small animals have to eat so much. 95% of calories goes to just generating heat

Big animals such as elephants have a fraction of the outsides compared to the volume. So when an elephant is making heat they have relatively little skin to dissipate all that heat they are generating inside of their body. They are more worried about getting too hot than being cold. This is why they have a greater buffer zone for their internal temperature. 106 degrees denatures proteins.

Question 2

How else does metabolism affect other functions?

Answer 2

Ties to that metabolism which is going to be very high for small thing and lower for big things is that things that go along with maintaining metabolism. to burn energy you need to get that oxygen around your body and also things like pulse rate and breathe rate are also included in this.

Pulse rate / respiration humans is around 4.5 heartbeats per respiration

Question 3

What are some constraints to an animals size

Answer 3

How animals move and how their body size and shape are affected by the cost of locomotion

Mechanical
•There are certain constrants that do not change: the law of thermodynamics, properties of water which includes density, viscosity, heat of evaporation and surface tension

Physical
•The physical strength of bones and tendons
•Muscle strength the cross sectional force of a piece of muscle is the same (an animal can only possess more or increase density of muscle)
•Lung volume - gas exchange is limited by body size
•Hematocrit - blood cells per volume
•Red blood cell size (same size in all mammals) - deliver oxygen

Question 4

What is Metabolic rate

Answer 4

The amount of energy you take in versus that amount of energy you expend

Question 5

What is BMR

Answer 5

Basal metabolic rate - base rate of energy need for simply living or normally surviving

Question 6

How much does BMR increase when an animal doubles in size? Why?

Answer 6

It does not double the metabolic rate and a mammal twice the size does not eat twice the amount of food. Actually metabolic demand and food intake only increase approximately 68%.
This is because of scale effect. As an animal is getting larger their volume to surface area ratio is changing and are no longer bleeding off as much heat. This means they don’t need to eat as much food which means their metabolic rate is lower.

Question 7

What are pros and cons of being a larger mammal?

Answer 7

Cons:
Physical and mechanical constraints

Pros:
1. Mass specific decrease in metablic rate which means less food is needed
2. Decrease cost of locomotion
3. Decrease predation

Question 8

Pygmy shrew - BMR

Answer 8

Weigh 3 grams
Normal BMR - 1000 bpm which is close to the upper limits of muscle physiology
Viscosity of blood - problem with getting to small
Red blood cell size - problem

Question 9

What size are most mammals?

Answer 9

Most mammals are small around the size of a domestic cat and develop means for low and high temperatures
•dense hair
•Protective inslatative nest
•Length of life generally correlated with size and lifestyle
• Metatherians shorter life than Eutherians
•Carnivore shorter life than herbivores

Question 10

Small vs large mammals

Answer 10

Question 11

What are the extant species of elephants and what are their characteristics

Answer 11

Elephas Maximus
Loxodonta Africana
Loxodonta Cyclotis - 2021

Question 12

General characteristics of Elephants

Answer 12

Max weight - 8 tons
Skeleton 12-15% of body weight
Sense of smell, hearing and touch are excellent
Do not have good eye sight
Use Infrasonic communication - travel up to 20 + miles
Proboscis - elongated flexible and muscular truck

Question 13

Elephant locomotion

Answer 13

Graviportal
Dictated by weight, with legs like pillars

• Ulna and radius as well as tibia and fibula same size
• Fiberous disc under toes acts as a cushion to reduce pressure

Question 14

How does form follow function in regards to Elephants

Answer 14

Form follow function
Elephas maximus - Southeast Asia in thick jungles being more compact in best interest
Loxodonta africana - savana - travel farther want to be tall with long legs because they need to cover a lot of ground and bigger because larger size decreases locomation effort
Loxodonta Cyclotis - forested but still in Africa - inbetween the two others

Question 15

Elephant dentition

Answer 15

Dental formula
1/0 (tusk - single upper incisor which are open rooted - they grow through out life - some loxodonta tusk can reach 10 ft long)

1/0 i, 0/0 c, 3/3 pm, 3/3 m = 26

Very large teeth for grinding, high crowned, complex molariform teeth (hypsodont)
Teeth do not succeed each other in a vertical fashion, but rather succeed each other in a verticle fashion. Essentially they move forward and replace from behind - mesial drift

Their teeth are very large and their jaw is relatively short and generally you can only see one molar at time (visible in each of the 4 quadrants at one time)

The have 6 teeth but they only have 1 in there at a time. What happens is that big molar comes in, develops they use it, they grind on it/chew and it is slowly moving forward and is getting worn down. When if finally gets to the front of the jaw it is tiny at that point and most of the time it just wears out and then is ejected.

They only have 6 so when they run out of usable teeth - most die because they run out of teeth

Question 16

Elephant food/feeding

Answer 16

Proboscidians are herbivores and can consume as much as 375lbs food a day
Non- ruminating herbivares, microbal fermentation takes place in the cecum - hindgut fermenters which means digestion is happening after the small intestine which is the site of abosorption making them inefficient.
Half of the material an elephant eats passes through undigested which is one of the reasons they need so much food a day.

Elephants come approx. 25-30 gallons of water a day

Question 17

Elephant lifestyle

Answer 17

They are capuscular, being active mostly at sunrise and sunset.

Relatively gregarious animals forming herds which are usually maternity based
Males are usually solitary except for breeding season

Life expectance approx. 80 years

Question 18

elephant conservation and problems

Answer 18

One of the boggest problems for elephants is habitat degradation
As the habitat that these elephants have gets smaller and smaller, they start knocking down trees to eat which creates additional issues because other animals live in that habitat.
Ex.) increased competition between rhinos and elephants for resources

Poaching for meat and tuck but is less of a problem today because of reduced ivory market and increased consequences.
Women elite militia - anti pouching South Afaica - Black mambas
Hard to sell ivory

Some parts of Africa have too many elephants

Question 19

Home ranges of Elephants

Answer 19

Daily movements can be as many as almost 20 miles a day and can have a home range of over 620 sq miles

Question 20

Elephants - reproduction

Answer 20

Gestation 22 months, afemales 2 - 5 young in a lifetime, at birth young way 200-350 lbs and
stand 3 ft tall
Sexually maturity 8-12 years of age maximum growth around 25

Question 21

Extinct spieces (elephants) that overlapped with humans

Answer 21

Extinct species
during pleistocene proboscidians occurred on every continent except Australia.
2 species overlap with humans
Mammilthus primigenuiies - wally mammoth Extinct 4,000 years ago
Mammut americananum - mastadon → 8,000 years

Question 22

General about Cetacea

Answer 22

Now a subgroup of Artiodactyla - even toed ungulates
38 - different genera which occur in 12 different families

Question 23

What are the 3 subgroups of Cetacea

Answer 23

Archaeoceti - extinct - had differentiated teeth, no longer than 3 meters , well-developed pelvic girdle

Odontoceti - toothed wales - homodont dentition

Mysticeti - Baleen whales - edentate

Question 24

Characteristics of Odontoceti vs Mysticeti

Answer 24

Odontoceti - Dentition often exceeds the typical Eutherian # (44) Example Bottle nose dolphin can have 200 teeth
- asymmetrical skull
- Single external nares (1 Nostril)
- As far as we know all use echolocation
~ 71+ species
~ 34 genera, 7 families

Mysticeti - Edentate but have baleen plates and can # from 130 plates to 400 plates. Baleen is attached to the upper jaw, nothing on the lower. Baleen is Keratinized tissue
- Sysmetrical sKulls
- 2 nares (nostrils)
- Don’t use echolocation
- 13 species

Question 25

7 groups of Odontoceti

Answer 25

1. Plantanistidae - freshwater dolphins, blind, no eyelids 2. Monodontidae- Narwhal and beluga 3. Phocoenidae- porpoises, don't have a beak, free cervical vertabrae, 6 species 4. Physeteridae - sperm whales 3 species 5. Delphinidae - beak, cervical vertabrae fused which limits neck mobility, 34ish species. 6. Ziphiidae - beaked whales, 21 species 7. Iniidae - Baiji, chinese river dolphines, 3 speices

Question 26

4 groups of Mysticeti

Answer 26

Mysticeti 1. Balaenidae- right whales, 4 species 2. Eschrichtidae- Ispecies, gray whale Balaenopteridae - tube throated, roquals, 7 species 4. Neobalaenidae- pigmy rightwhale, 1 species

Question 27

General characteristics about Cetacea

Answer 27

• 50 -136 tons • 4ft - 120 ft • tail- Fluke set in horizontal plane • fusiform body shape • frontlimbs are modified flippers • Greater than typical # of phalanges • Hind limbs absent • Adaptations for increased laminar flow • No external projections • No hair instead they have blubber - fibrous tissue that acts as insulation for heat retention and regulation • Bones somewhat spongy texture also filled w/oil • Some speices the cervical vertebrae are fused • All cetaceans lack complex articulation of the cervical vertebrae which helps Keep face pointed in the correct direction to move efficiently through water - ridged axial skeleton • telescoped skull • Nostals can externally through top of head • blow holes can be closed muscularly - myth that they blow water out of nostrils -exhale in cold water • Structure of baleen plates variable mysticeti

Question 28

What are the two feeding modes used by Mysticeti?

Answer 28

Skimming mode - open mouth swim through water water pressure comes in and wants to escape very large plates of Baleen - Right Whales Gulpers - gulp a large volume of water and food into their mouth and then use the force of their tounge to filter water through baleen. Possess smaller baleen plates and are able to unhinge lower jaw to open mouth super wide up to 19,000 Gallon = 64 tons of water 1 gulp - Blue Whale Bubble nets

Question 29

Size and relation to prey in Whales and why

Answer 29

Larger whales eat smaller prey and smaller whales eat larger prey most likely due to maneuverability, large whales don’t have to be agile to catch small prey and vice versa

Question 30

Why do Whales use Echolocation and what are some issues with Echolocation in the water

Answer 30

Water is a poor transmitter of light or they live in murky water so they use it to gather information about their sounding. Issues: • Sound travels faster in water than in air (sound hits your ears pretty close to the same time because it’s moving so quickly • Head is full of water and so it kind of goes straight through to you other ear which throws of calculations

Question 31

What are 3 difffernt attributes whale have to offset issues with echolocation in the water

Answer 31

1: Their ears are insulated from their skull. The area around the ear is filled with a special mucus oil emulsion. (If it was filled with air and dove deep it would collapse). This provides the insulation they need to prevent sound from moving across but it is completely resistant to pressure changes up to 100 atmospheres (3300 feet without pressure in cavity) 2. Melon - special organ- structure on top of whales head - acts as an acoustical lens, Sound will enter into the melon and then it will focus that sound. Skill acts as radar dish in away of bouncing sound into this acoustic lens. They can adjust the shape of the melon which will focus the beam 3. Lower jaw - sound waves come back and hit the lower jaw which is hollow and filled with oily substance. Acts as ears by catching sound waves and channeling them up to the free floating auditory bulla near the end of the lower jaw.

Question 32

How is echolocation different in sperm whales

Answer 32

They have spermaceti above the melon. Sound waves generated and are funneled into the spermaceti which then funnels back sounds. then bounces off the skull and holes into the melon which then makes the sound come out the front of the face The time between clicks is an indication of the size of the whale because it takes a long time for it to go through so there is a longer interval Because of the structure of the sperm whale they are able to make some of the loudest noises with the loudest echolocation calls underwater. There is a lot of evidence to suggest that they are using echolocation calls to stun prey

Question 33

What are some issues with diving deep

Answer 33

Every 10 metered or 33ft down an atmosphere of pressure is added Bends - have it to much nitrogen in blood Components of air - oxygen 20% Nitrogen 78% Near or at the surface level nitrogen molecules are not much of a problem because they are too large for most to enter and diffuse through the cell walls easily. The pressure from diving deep compresses nitrogen molecules and allows them to pass through and enter the bloodstream quite easily. If you dive down deep then come back up too quickly then they start to return to their larger size and collect together and you end up with nitrogen bubbles in your bloodstream which is a corn if it goes to the brain or heart.

Question 34

How do whales avoid getting the bends and pressure when deep diving

Answer 34

• When whales go down they are not breathing and even exhale before diving • Oxygen stored in myoglobin (a part of muscles) and in hemoglobin (blood) • Whales store a lot of oxygen in bloodstream and myoglobin • Whales are more efficient at obtaining oxygen 3x more (12%) than us at 4% which means they replenish their supply/stores faster • Whales can withstand higher concentrations of CO2 and lactic acid • Hermatocrit - the number of red blood cells for volume of blood. All animals have the same amount except whales which have 2 times the amount which means they have twice the amount of red blood cells in their bloodstream and they can carry twice the amount of oxygen • Whales also have 2 to 9 times the myoglobin that we do as terrestrial mammals which means they can store up to 9 times as much oxygen in their muscles . • Massive oxygen bank built into their body • Bradycardia - reducing heat rate during diving which decreases the amount of oxygen consumed • Diving response - the body shuts down blood supply in the peripheral part of the body and focuses it in just the core - Myoglobin stores in muscles - Brain has no muscle so keeping oxygen rich blood focused on Brian and heart is importance • Pressure - bone flex- spongy compacted to ours and also possess a rib joint Whales can stay down as long as 2 hrs

Question 35

What are some additional adaptions that only sperm whales have

Answer 35

Odontoceti have a singe nostril. Sperm whales nasal passage is greatly modified. Ways they decrease energy to go up and down in water: • Spermaceti has a melting point from solid to liquid somewhere around room temperature • Vestibular sac infront and Nasofrontal sac in back are connected in oval circit by 2 nasal passages (split system) • They can suck in cold ocean water and circulate it around its nasal passages back and forth which solidity spermaceti, and turns it into an anchor to go down • To return up stores water in Nasafrantal sac which was warmed up by body temp (near brain) and will then liquify the spermaceti • Adjust Buoyancy - circulate water back 3 forth

Question 36

Whales and vocalizations

Answer 36

Vocalizations are different than echolocation - Echolocation is about finding intormation - Vocalizations are about communication Vocalizations in both in odonticeti and mysticeti but many mysticeti - Humpback whale are known the most for this : - Humpoack whales during migration before getting to breeding grounds there is some courting. The whales travel in groups and so males try to impress females by song. Each male retreats and adds on to the song Different kinds of calls that have some kind of communication Right whales - 6 distinct calls

Question 37

Most Whales are endangered why and attempts to mitigate

Answer 37

Right whales - 1st to be overharvested - Placed on the endangered species list (1936) Rightwhales - when killed they would float back up would not sink boats 1930/1940'5/1950's boats are larger and more advanced - Killed other whales 1946 the IWC- International Whaling Commison was created because whales are international. Problem there are only 2 ways to get countries to do what you want - War or pay them off So the IWC had no authority and only existed in name Initially they were attempting to set and create a system (point based) to regulate but failed Countries started to make up excuses such as claiming it was for research and science.