Chapter 8

Question 1

quadrupedalism

Answer 1

locomotion using for limbs, with hands and feet moving on a surface such as the ground or top of a branch of a tree

Question 2

pronograde

Answer 2

posture with the body held parallel to the ground

Question 3

branch running an walking

Answer 3

a form of quadrupedalism in which the animal is walking along a branch, grasping with both hands and feet

Question 4

ground running and walking

Answer 4

a form of quadrupedalism that takes place on the ground as opposed to in the trees

Question 5

Old World semibrachiation

Answer 5

locomotor pattern involving extensive use of hands, but not the tail, in leaping in a basically quadrupedal animal

Question 6

New World semibrachiation

Answer 6

locomotor pattern involving extensive use of hands and prehensile tail to suspend and propel the body in species otherwise quadrupedal

Question 7

slow climbing

Answer 7

locomotor pattern in which the animal moves slowly and cautiously without leaping

Question 8

orthograde

Answer 8

vertical posture

Question 9

vertical clinging and leaping

Answer 9

a method of locomotion in which the animal clings vertically to a branch and moves between branches by leaping vertically from one to another. The animal moves on the ground by hopping or moves bipedally

Question 10

suspensory behavior

Answer 10

form of locomotion and posture whereby animals suspend themselves underneath a branch

Question 11

true brachiation

Answer 11

hand-over-hand locomotion along a branch with the body suspended underneath the branch by the arms

Question 12

quadrumanous locomotion

Answer 12

locomotor pattern found among orangutans, who often suspend themselves under branches and move slowly using both forelimbs and hindlimbs

Question 13

knuckle walking

Answer 13

semierect quadrupedalism, found in chimpanzees and gorillas with upper parts of the body supported by the knuckles as opposed to palms

Question 14

erect bipedalism

Answer 14

a form of locomotion found in humans in which the body is maintained in an upright posture on two legs while moving by means of heel-toe stride

Question 15

heel-toe stride

Answer 15

method of progression characteristics of humans where the heel strikes the ground first; the person pushes off on the big toe

Question 16

intermembral index

Answer 16

the length of the humerus and radius relative to the length of the femur and tibia

Question 17

lumbar curve

Answer 17

a curve that forms in the lumbar region of the spine in humans

Question 18

gluteus maximus

Answer 18

in humans, the largest muscle of the body; acts as an extensor, extending the leg in running and climbing

Question 19

gluteus medius & minimus

Answer 19

muscle of the pelvis that in monkeys and apes acts as an extensor, but in humans acts as an abductor

Question 20

extensor

Answer 20

a muscle that straightens out the bones about a joint

Question 21

abductors

Answer 21

muscles that move a part of the body away from the midline of the body

Question 22

brachial index

Answer 22

the length of the radius relative to the length of the humerus

Question 23

crucal index

Answer 23

the length of the tibia relative to the length of the femur

Question 24

power grip

Answer 24

a grip in which an object is held between the fingers and the palm with the thumb reinforcing the fingers

Question 25

precision grip

Answer 25

a grip in which an object is held between one or more fingers with the thumb fully opposed to the fingertips

Question 26

occipital condyles

Answer 26

two rounded projections on either side of the foramen magnum that fit into a pair of sockets on the top of the spine, thus articulating the skull with the spine

Question 27

foramen magnum

Answer 27

a large opening in the occipital bone at the base of the skull through which the spinal cord passes

Question 28

nuchal muscle

Answer 28

the muscle in the back of the neck that functions to hold the head up. In primates with heavy facial skeletons, the large nuchal muscle attaches to a nuchal crest

Question 29

nuchal crest

Answer 29

flange of bone in the occipital region of the skull that serves as the attachment of the nuchal musculature of the back of the neck

Question 30

prognathism

Answer 30

a jutting forward of the facial skeleton and jaws

Question 31

forebrain

Answer 31

the anterior of three swellings in the hollow nerve cord of the primitive vertebrae brain formed by a thickening of the wall of the nerve cord

Question 32

midbrain

Answer 32

the middle of the three swellings in the hollow nerve cord of the primitive vertebrae brain formed by a thickening of the wall of the nerve cord

Question 33

hindbrain

Answer 33

the posterior of the three swellings

Question 34

neocortex

Answer 34

gray covering on the cerebrum of some vertebraes; site of higher mental processes

Question 35

cerebral cortex

Answer 35

the “gray matter” of the brain; the center of conscious evaluation, planning, skill, speech, and other higher mental activities

Question 36

allometric growth

Answer 36

patterns of growth whereby different parts of the body grow at different rates with respect to each other

Question 37

encephalization quotient

Answer 37

a number reflecting the increase in brain size over and beyond that explainable by an increase in body size

Question 38

social intelligence

Answer 38

the knowledge and images that originate in an individual’s brain that are transferred by speech to the brain of others

Question 39

cranial capacity

Answer 39

the volume of the brain case of the skull

Question 40

endocranical cast

Answer 40

a cast of the inside of the brain case

Question 41

cheek teeth

Answer 41

the premolars and molars

Question 42

cusps

Answer 42

points on a tooth

Question 43

insectivores

Answer 43

animals that eat primarily insects; also members of the mammalian order insectivora

Question 44

frugivores

Answer 44

animals that eat primarily fruits

Question 45

folivores

Answer 45

animals that eat leaves

Question 46

omnivores

Answer 46

animals that eat a variety of different kinds of food

Question 47

dental formula

Answer 47

2:1:2:3

Question 48

dental arcade

Answer 48

the tooth row as seen from above

Question 49

diastema

Answer 49

a space between teeth

Question 50

sectorial premolar

Answer 50

unicusped first lower premolar with a shearing edge

Question 51

Y-5 pattern

Answer 51

pattern found on molars with 5 cusps, separated by grooves, reminiscent of the letter Y

Question 52

simian shelf

Answer 52

a bony buttress on the inner surface of the foremost part of the ape mandible, functioning to reinforce the mandible

Question 53

chin

Answer 53

a bony projection of the lower border that arises on the side of the skull and inserts on the jaw

Question 54

temporalis

Answer 54

a muscle of chewing that arises on the side of the skull and is used for chewing, inserts on jaw

Question 55

sagittal crest

Answer 55

ridge of bone along the midline of the to of the skull that serves for the attachment of the temporalis muscle

Question 56

masseter

Answer 56

a muscle of chewing that arises on the zygomatic arch of the skill and inserts on the mandible