CHAPTER 4 - Moving Around

Question 1

Lizards, turtles, crocodiles, and salamanders all have what is termed a __ Stance

Answer 1

sprawling stance.

Question 2

Mammals and birds have what is termed __ Stance

Answer 2

erect stance

Question 3

One advantage is that an erect stance positions the limb bones directly under the body. This allows

Answer 3

the limb bones to passively support the body’s weight without muscles having to strain.

Question 4

Another advantage of erect posture is that it allows all the limb bones to contribute

Answer 4

the length of a stride. This improves speed, because, if every step you take is longer, you can potentially cover ground more quickly.

Question 5

Birds and mammals evolved their erect stances __ of each other

Answer 5

independently

Question 6

An erect posture is advantageous for

Answer 6

fast locomotion and for supporting body weight.

Question 7

Cursorial limbs are

Answer 7

limbs specially adapted for fast locomotion. cursorial limbs are elongated.

Question 8

digitigrade posture

Answer 8

standing on toes

Question 9

stand only on toenails that have been modified into hoofs

Answer 9

unguligrade posture

Question 10

plantigrade posture

Answer 10

simultaneously on our toes, the flat of our feet, and our heels

Question 11

Some dinosaurs show cursorial adaptations, in particular the

Answer 11

ornithomimid theropods

Question 12

Ornithomimids have a __stance and long __.

Answer 12

digitigrade Metatarsals

Question 13

adapted for supporting extreme body weight.

Answer 13

Graviportal limbs

Question 14

Animals that almost always walk and run on two legs, like birds and adult humans, are termed

Answer 14

obligate bipeds.

Question 15

Animals that almost always walk and run on four legs, like turtles and horses, are termed

Answer 15

obligate quadrupeds

Question 16

walk on all four legs but rise on two legs to run

Answer 16

facultative bipeds ex. Basalisks, kangaroo, gorillas

Question 17

The ancestor of all dinosaurs was an (what type of posture)

Answer 17

obligate biped

Question 18

Nevertheless, we classify sauropods, stegosaurs, and ankylosaurs as

Answer 18

obligate quadrupeds

Question 19

Both of the major groups have strong hind legs that are significantly longer than their front limbs. This indicated

Answer 19

bipedal stance

Question 20

Ichnofossils are fossils that record traces of

Answer 20

biologic activity (footprint, tooth marks, burrows)

Question 21

Fossil footprints, tooth marks, and burrows are all examples of

Answer 21

ichnofossils

Question 22

an entire series of dinosaur footprints are called

Answer 22

trackways.

Question 23

The trackways of hadrosaurs and iguanodonts have deep imprints left by their ____ ____and
show that these dinosaurs carried most of their weight on their ___ ___

Answer 23

hind feet, hind legs

Question 24

ectotherm to refer to

Answer 24

“cold-blooded” animals that adjust their internal body temperatures through behaviors that depend on temperature changes in the environment

Question 25

Endotherms are animals that

Answer 25

regulate their own body temperatures through metabolic processes. To warm up, endotherms burn energy to generate internal heat, and, to cool down, they may sweat or pant.

Question 26

Advantages of being an endotherm

Answer 26

• can survive in warm places
• always ready for action
• do not waste time trying to find places or sitting in places to generate body heat

Question 27

Histology is the technique

Answer 27

of slicing samples of bones into very thin sections, such that the internal structure of the bone can be observed under magnification.

Question 28

Bone cells are called

Answer 28

osteons.We know from studies of modern animals that endotherms grow their bones more quickly and have their osteons arranged in a different pattern than ectotherms.

Question 29

cube square law

Answer 29

As any shape increases in size, its surface area increases more slowly than its volume

Question 30

gigantothermic

Answer 30

is a phenomenon stating ectothermic animals are more easily able to maintain a constant, relatively high body temperature than smaller animals by virtue of their smaller surface area to volume ratio