Chapter 3

Question 1

what are the two aspects of locomotion?

Answer 1

forward progress and directional control

Question 2

how do the 5 types of swimming modes most differ? (3 ways)

Answer 2

i) the proportion of the body that undulates (oscillates)
ii) the amount that the head moves (yaw)
iii) morphology

Question 3

Sinusoidal undulation

Answer 3

throwing the body into a series of successive ‘S’-shaped curves

Question 4

What is the most primitive mode of swimming in vertebrates?

Answer 4

Anguilliform

Question 5

All fishes use which mode of swimming at least once in their life?

Answer 5

sinusoidal

Question 6

what are the three lines of evidence that support the theory of Anguilliform’s primitiveness?

Answer 6

i) sideways undulation
ii) most fishes start out using anuilliform in their larval stages
iii) vetebrates are bilaterally symmetrical

Question 7

briefly describe the motion of anguilliform locomotion

Answer 7

successive waves of muscular contraction pass along alternate sides of the body.
the lateral components of force cancel each other out, resulting movement is forward

Question 8

how do anguilliformes slow down or stop?

Answer 8

hold the curved body rigid,

Question 9

anguilliform swimming is related to what body type?

Answer 9

long, slender bodies with reduced or absent caudal fins

Question 10

is high speed possible with anguilliform swimming?

Answer 10

nope

Question 11

How are caudal swimmers different from anguilliform swimmers?

Answer 11

the distribution of body bulk and the effect of contracting the body muscles in the tail region.

Question 12

what did Langerhans and Reznick’s research suggest?

Answer 12

that subtle differences between stream environments can lead to selection for different swimming morphologies within the same species.

Question 13

what are the four sub-categories of carangiform swimming methods?

Answer 13

Subcarangiform, Carangiform, Thunniform, Ostraciiform

Question 14

how much musculature is needed for subcarangiform swimming?

Answer 14

two thirds

Question 15

What type of swimmer is a salmon?

Answer 15

subcarangiform

Question 16

is the caudal fin the major propulsive force in subcanrangiform swimming?

Answer 16

nope. you could cut it off and the suckers would still go. The caudal fin helps with rapid acceleration, fast turning, and high speed maneuverability.

Question 17

what part of the body is used for canrangiform locomotion?

Answer 17

only the posterior 1/3 part of the body

Question 18

what two major evolutionary developments occurred?

Answer 18

i) become more laterally compressed and deeper bodied, unpaired fins became stiffened with spines
ii) depth of the caudal peduncle has become greatly reduced, reducing turbulence and drag, increasing the frequency in which the tail beats.

Question 19

how has the development of keels impacted the drag?

Answer 19

increase the hydrodynamic shape of the the caudal peduncle

Question 20

how is thrust generated in Thunniform swimmers?

Answer 20

almost exclusively by a high (lunate), stiff and deeply forked caudal fin mounted on an extremely narrow caudal peduncle, typically with stiff keels.

Question 21

are thunniform swimmers always warm blooded?

Answer 21

yup

Question 22

even though Oscillaformes vary greatly in body shape, what can be common of these swimmers?

Answer 22

they tend to be fishes with bodies incaed in armour and or weaponry

Question 23

what the heck is Tetraodontiform locomotion?

Answer 23

fishes who propel themselves by passing waves of movement down their elongate dorsal and/or anal fins

Question 24

what do you call fish who propel themselves by rapid undulation of the pectoral fins?

Answer 24

Rajiform or Labriform locomotion

Question 25

name some non-swimming locomotions

Answer 25

jet propulsion, terrestrial locomotion, walking and burrowing, jumping, gliding, and true flying.

Question 26

name some nearly finless fishes

Answer 26

hagfish, lamprey, true eels, swamp eels

Question 27

name three roles that fins play

Answer 27

i) aid/produce forward movement
ii) guide the course of forward movement
iii) system of brakes, mechanism for backing up

Question 28

what is a major evolutionary theme for fins?

Answer 28

increasing functional efficiency and specialization.

Question 29

what are the five regions for fin placement over the body?

Answer 29

i) anterior zone of rudders
ii) posterior zone of rudders
iii) zone of keels
iv) zone of stabilizers
v) zone of thrust

Question 30

what are the three curses of living in a ‘giving medium’?

Answer 30

yaw, pitch and roll

Question 31

which fins are the least specialized? how do they aid?

Answer 31

dorsal and anal, forward motion, braking, stabilizers

Question 32

the dorsal fin lies over what?

Answer 32

the centre of gravity

Question 33

what is an anal fin’s main job?

Answer 33

to act as a stabilizer

Question 34

what is the caudal fin’s main job?

Answer 34

organ of thrust

Question 35

what is a dorsal fin’s main job?

Answer 35

lies above the centre of gravity, functions as a dorsal keel to prevent rolling

Question 36

what are paired fins main job?

Answer 36

they serve as rudders to control vertical position.

Question 37

the evolution changing of position of pectoral fins have provided which new capabilities?

Answer 37

i) maintain a stationary position in the watter by fanning the pectorals
ii) ability to clap the extended pectorals sharply back to accelerate rapidly

Question 38

how is it possible that evolutionary changes occured in fin placement and function?

Answer 38

with the evolution of the swim bladder.