Locomotion in Vertebrates

Question 1

What are the different forms of locomotion in vertebrates?

Answer 1

Swimming
Walking and Running
Jumping (Saltatory) Locomotion
Parachuting, Gliding, and Flight

Question 2

What are the different types of swimmers?

Answer 2

Primary (fish already there) and Secondary (animals from the land that went back to water) swimmers

Question 3

What are the characteristics of a primary swimmer?

Answer 3

They consist of fish and aquatic amphibians

Most are undulatory swimmers

Question 4

What are the characteristics of a secondary swimmer?

Answer 4

Consist of sea turtles, penguins, alligators, pinnipeds, cetaceans
Most are oscillatory swimmers, others are undulatory

Question 5

How do undulatory swimmers swim?

Answer 5

Use their body wall muscles for body movement and propel themselves with lateral undulations

Question 6

How do oscillatory swimmers swim?

Answer 6

Propel themselves with oscillations or paddle-like movements of their tail or paired appendages

Question 7

Are there undulatory swimmers that use paired fins?

Answer 7

Yes, the bowfin and stingray

Question 8

What are the different types of undulatory swimmers?

Answer 8

Anguilliform (more than half of body)
Carangiform (about half of body)
Thunniform (less than half, just tail)
Ostraciform (only use tail, rest of body is rigid)

Question 9

Why would penguins be good swimmers?

Answer 9

Evolved from ancestors with very strong pectoral muscles

Question 10

Were ancient fish good swimmers?

Answer 10

Most had caudal fins, so probably could swim
Lack other fins, so probably lacked control
Their lifestyle was sitting at the bottom of the ocean floor with dermal armour and they weren’t dominating at the time, it was the invertebrates

Question 11

What are some problems with locomotion in water?

Answer 11

Drag (this and buoy. = density of h2o)
Buoyancy
Specific heat of water

Question 12

What is drag and what does it do?

Answer 12

It collectively refers to the frictional and other forces that tend to hold the fish back

Question 13

How are fish adapted to swim in the water?

Answer 13

The vertebral centra are spool-shaped so it resists against the compressional forces in the water
Also, have a fusiform shape to minimize drag

Question 14

What are the differences between frictional drag and pressure drag?

Answer 14

Frictional drag is the frictional force exerted on the fish due to the viscosity of the water
Pressure drag results from differences in water pressure between the front and rear of the fish

Question 15

What is the boundary layer and what does it associate with?

Answer 15

It is the thin layer of water that surrounds a moving fish
The mucous secreted by a fish allows the water to associate with it, creating a layer of water over cop of the fish, decreasing drag

Question 16

How do you decrease frictional drag?

Answer 16

Low surface area : mass ratio
Fish is swimming slowly
Water flows smoothly across the surface (flow is laminar)

Question 17

How do you reduce pressure drag?

Answer 17

Depends on body shape: more streamlined = less pressure drag

Question 18

How does pressure drag slow a fish down?

Answer 18

There is a high pressure at the head and low pressure over the posterior part, causing a negative pressure that essentially vacuums the fish backwards

Question 19

Why is buoyancy a problem for swimming?

Answer 19

If you are sinking to the bottom, you won’t be a good swimmer

Question 20

How do Chondrichthyes overcome buoyancy problems?

Answer 20

Cartilage instead of bone, which is less dense
Lipids in liver (squalene), also decreases density
Head shape, fins, heterocercal tail together create a straight motion for swimming

Question 21

How are Osteichthyes adapted for buoyancy?

Answer 21

Actinopteyrgii

Swim bladder full of air allows them to be a bit heaver (bone, etc)

Question 22

Why is the specific heat of water a problem?

Answer 22

The specific heat of water allows it to absorb heat quick, but not give it up
For ectotherms, it isn’t really a problem since their body temperature isn’t tightly regulated
For endotherms, their body temperatures are rigidly controlled, so tend to have a thick later of skin for insulation (subcutaneous fat) preventing heat loss

Question 23

What are the different phases of the step cycle?

Answer 23

Propulsive phase –> swing phase

Question 24

What is the difference between a step and a stride?

Answer 24

One stride is a step cycle for both legs (left foot to left foot), while a step is just for one leg (left foot to right foot)

Question 25

Describe the step cycle in amphibians and reptiles

Answer 25

Undulating movements of the body (sinusoidal) Limbs tend to be splayed out (horizontal plane) Snakes have undulating movements and use friction as well Alligator had a less undulating movement (more limb muscles probably)

Question 26

Describe the step cycle in mammals

Answer 26

Limbs are rotated underneath the body = vertical plane of movement Cursorial (runners) vs non cursorial

Question 27

What is the difference in the pronghorn and prairie dog? Why?

Answer 27

The pronghorn is the fastest mammal in N.A. Run fast probably because had pressure from predators who are now extinct Praire dog is plantigrade and a burrowing animal

Question 28

What is a gait?

Answer 28

The particular combination of feet that are on and off a ground during a stride

Question 29

What is the difference between walking and running?

Answer 29

There is never a flight phase in walking (there is always 1 limb on the ground)

Question 30

What are some different ways of running?

Answer 30

Symmetrical (trot) - 2 legs in symmetry | Assymmetrical (gallop) - all 4 are out of phase, and it is generally faster with a longer suspension phase

Question 31

What is the formula for calculating speed?

Answer 31

Velocity = F (stride frequency) x L (stride length)

Question 32

How is the cheetah adapted for speed?

Answer 32

It can add to its stride length by flexing its back in its lumbar region. Also, its hind limbs come far forward due to powerful propulsive phase If it couldn't do this, it wouldn't be able to outrun an antelope, which has long legs so should be faster

Question 33

What are the different toes of foot posture?

Answer 33

Plantigrade - wrist bones touch ground Digitigrade - step on fingers Unguligrade - only last phalange hits ground

Question 34

What types of foot postures are typical for a cursorial mammal?

Answer 34

Digitigrade and unguligrade

Question 35

How are unguligrade animals at an advantage?

Answer 35

Even if their bones were the same length, they would have a longer stride length. Also, more joints in the leg means more muscle attachments

Question 36

How is a frog specialized for jumping?

Answer 36

No tail, shortened strong thick vertebral column, powerful hind limbs, specialized pelvis and sacrum, radio ulna, sacroiliac joint (allows for lots of bend)

Question 37

How does a frog jump?

Answer 37

First it pushes off its front limbs, then off its hind limbs and pulls its hind limbs in to reduce drag and lands on front limbs which are strong

Question 38

How is kangaroo jumping different than the frog?

Answer 38

Its forelimbs are not involved, no crouching, and it has a long tail

Question 39

Why is the tail of a kangaroo important?

Answer 39

It acts as a counter balance

Question 40

How are the tendons of a kangaroo specialized?

Answer 40

They have a large Achilles tendon which a lot of elastic tissue When it lands, it gains potential energy which it can use for its jump. So it is actually hard for kangaroos to jump slowly

Question 41

Why is parachuting important?

Answer 41

It allows an animal to break a fall and escape a predator

Question 42

How do you have to be adapted to parachute?

Answer 42

You have to have lots of surface area and low weight

Question 43

What is the difference with gliding compared to parachuting?

Answer 43

Gliding usually lets animals travel slower and also moves them in the horizontal component

Question 44

What are some examples of animals that parachute?

Answer 44

Tree frogs, arboreal lizards

Question 45

What are some examples of animals that glide?

Answer 45

Lizards, flying squirrel, flying fish, flying snake

Question 46

How do flying fish glide?

Answer 46

They have long pectoral fins which is an advantage to get out of the water, but it makes them bad swimmers. First they shake off the water from their pec. fins and while they do this, the undulate their tail to get more speed and distance. Once they are in the air, they just glide

Question 47

How are wings shaped for flying?

Answer 47

An airfoil shape, which is similar to a fusiform shape, but asymmetric It is to decrease drag

Question 48

What are the physics behind flight?

Answer 48

In order to fly, first the wing must cut through the air. This causes wind to go either above or below the wing, where below is less distance. This means that on top it must go faster, so it has a low pressure on top. This creates a negative pressure at top, and creates a vacuum, causing lift.

Question 49

What is the formula for calculating lift?

Answer 49

Lift (L) = 1/2pV^2SC

Question 50

What two parts of the formula are variable between different birds?

Answer 50

Air speed (V) and area of wing (S)

Question 51

What do slow flying birds have? Give an example of one.

Answer 51

They have low V, and high S | Eg. Vultures

Question 52

What do rapidly flying birds do? Give an example of one.

Answer 52

They have a high V, low S | Eg. Loons

Question 53

How do you calculate wing loading? What does it represent?

Answer 53

Wingloading = weight/S.A. of wings For vultures = 0.3, Loons = 1.4 The higher the wing loading, the faster the bird has to fly to keep in the air?????

Question 54

In particular, how do birds fly?

Answer 54

Wings flapping do not create lift, instead it is air passing over the wing airfoils ASK TONY

Question 55

How do bats fly?

Answer 55

ASK TONY

Question 56

How are hummingbirds specialized?

Answer 56

When they hover, they move their wings in a figure 8 motion In the forward movement, it causes lift. Backstroke is for recovery They can flap their wings at 15-83 times per second, while a goose does 12-70 per min

Question 57

What is a soarer? What are the different types?

Answer 57

A bird that can fly for long periods of time without flapping wings Static and dynamic

Question 58

Whats the difference between a static and dynamic soarer?

Answer 58

Static soarers tend to soar when its hot out. They use the fact hot air rises to their advantage. These birds tend to have low wing loading (eg. vulture) Dynamic soarers live close to water, using the coastal winds to help them create lift. Large S.A. but instead of broad, they are long (eg. albatross)

Question 59

What are some adjustments birds make during fast flight that prevent excess energy use?

Answer 59

Birds retract their feet, body becomes more horizontal, opened its mouth to get air into air sacs, head is pretty stable while body oscillates (neck adjusts to keep head stationary)

Question 60

What advantages do fixed (plane) wings have over flapping (bird) wings?

Answer 60

``` Adv = stability Disadv = Manoeuvrability decreases ```

Question 61

How are birds adapted for flight?

Answer 61

``` Light skeleton (spongy bone), feathers beak Large sternum with keel Rib spurs to prevent collapse Breathing - air flows 1 direction Reproductive adaptation - 1 ovary Nutrition - meat = high energy diets ```

Question 62

What are the theories for flight?

Answer 62

1. Arboreal flight 2. Running flight 3. Wing Assisted Incline Running (W.A.I.R.)

Question 63

What is the arboreal flight theory?

Answer 63

Dinosaurs that used to be able to climb trees would glide from tree to tree (if they had good S.A. on pectoral limbs)

Question 64

What is the running flight theory?

Answer 64

Since most dinosaurs don't look arboreal because theropods had weak forelimbs, this is a better theory While dinosaurs ran, they jumped from obstacles. If they had feathers and jumped, could jump glide and increase maneuvarability

Question 65

What is the W.A.I.R. theory?

Answer 65

Wings could be used to help climb steep substrates - could climb substrates their predators didn't and when on top of the "rock", glide down to other side.

Question 66

How do the different types of locomotion rank in terms of energy? (from most to least)

Answer 66

Burrowing, runners, flying, and swimming (buoyancy helps)