Lec 4 Locomotion

Question 1

two aspects of locomotion

Answer 1

forward progress and directional control

Question 2

ANGUILLIFORM LOCOMOTION

Answer 2

Sinusoidal undulation of the body—throwing the body into a series of successive S-shaped curves—seems to be the basic or primitive mode of swimming in vertebrates. inefficient mode of locomotion. High speed is impossible

Question 3

Tail waggers, caudal motion

Answer 3

caudal (tail) type of propulsion found in most bony fishes. propel themselves forward, they rely on a much smaller part of the body. distribution of body bulk, most of which is forward in more derived fishes

Question 4

Caudal swimming : SALMONIFORM LOCOMOTION

Answer 4

approximately two-thirds to one- half of the body is involved in producing the propulsive wave. typically have large well-developed but flexible caudal fins that can be opened or shut to increase or reduce fin area by as much as 10% during a single tail beat. Ex salmon

Question 5

Caudal swimming, CARANGIFORM LOCOMOTION

Answer 5

posterior part of the fish is capable of large flexure. The caudal fin is stiff and often deeply forked. Drag is reduced by shape of fin. Ex mackerels and herrings

Question 6

Caudal swimming, THUNNIFORM LOCOMOTION

Answer 6

caudal locomotion developed to the extreme. It represents the extreme end-point in an evolutionary trend toward greater speed. Burst of speed from stiff, and deeply forked caudal fin mounted on an extremely narrow caudal peduncle. Ex tuna and sharks

Question 7

Caudal swimming, OSTRACIIFORM LOCOMOTION

Answer 7

propulsion comes from “wagging” the tail, rather than by passing a wave of musculature contraction down the length of the body. Tend to be slow swimmers. Ex box fishes and rays

Question 8

Tetraodontiform locomotion

Answer 8

propel themselves by passing waves of movement down their elongate dorsal and/or anal fins. Ex puffer, trigger fishes

Question 9

Fin function

Answer 9

fins of fishes function primarily to control the direction of forward progress.
1. They often aid in forward movement 2. They guide the course of forward movement 3. They provide a system of brakes and/or a mechanism for backing up

Question 10

Some finless fishes

Answer 10

hagfishes (Myxinidae) and lampreys (Petromyzontidae), a few groups of true eels (e.g., spaghetti eels, Moringuidae; some morays, Muraenidae) and some swamp eels (family Synbranchidae.