Chapter 8 Flashcards
quadrupedalism
locomotion using for limbs, with hands and feet moving on a surface such as the ground or top of a branch of a tree
pronograde
posture with the body held parallel to the ground
branch running an walking
a form of quadrupedalism in which the animal is walking along a branch, grasping with both hands and feet
ground running and walking
a form of quadrupedalism that takes place on the ground as opposed to in the trees
Old World semibrachiation
locomotor pattern involving extensive use of hands, but not the tail, in leaping in a basically quadrupedal animal
New World semibrachiation
locomotor pattern involving extensive use of hands and prehensile tail to suspend and propel the body in species otherwise quadrupedal
slow climbing
locomotor pattern in which the animal moves slowly and cautiously without leaping
orthograde
vertical posture
vertical clinging and leaping
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
suspensory behavior
form of locomotion and posture whereby animals suspend themselves underneath a branch
true brachiation
hand-over-hand locomotion along a branch with the body suspended underneath the branch by the arms
quadrumanous locomotion
locomotor pattern found among orangutans, who often suspend themselves under branches and move slowly using both forelimbs and hindlimbs
knuckle walking
semierect quadrupedalism, found in chimpanzees and gorillas with upper parts of the body supported by the knuckles as opposed to palms
erect bipedalism
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
heel-toe stride
method of progression characteristics of humans where the heel strikes the ground first; the person pushes off on the big toe
intermembral index
the length of the humerus and radius relative to the length of the femur and tibia
lumbar curve
a curve that forms in the lumbar region of the spine in humans
gluteus maximus
in humans, the largest muscle of the body; acts as an extensor, extending the leg in running and climbing
gluteus medius & minimus
muscle of the pelvis that in monkeys and apes acts as an extensor, but in humans acts as an abductor
extensor
a muscle that straightens out the bones about a joint
abductors
muscles that move a part of the body away from the midline of the body
brachial index
the length of the radius relative to the length of the humerus
crucal index
the length of the tibia relative to the length of the femur
power grip
a grip in which an object is held between the fingers and the palm with the thumb reinforcing the fingers
precision grip
a grip in which an object is held between one or more fingers with the thumb fully opposed to the fingertips
occipital condyles
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
foramen magnum
a large opening in the occipital bone at the base of the skull through which the spinal cord passes
nuchal muscle
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
nuchal crest
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
prognathism
a jutting forward of the facial skeleton and jaws
forebrain
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
midbrain
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
hindbrain
the posterior of the three swellings
neocortex
gray covering on the cerebrum of some vertebraes; site of higher mental processes
cerebral cortex
the “gray matter” of the brain; the center of conscious evaluation, planning, skill, speech, and other higher mental activities
allometric growth
patterns of growth whereby different parts of the body grow at different rates with respect to each other
encephalization quotient
a number reflecting the increase in brain size over and beyond that explainable by an increase in body size
social intelligence
the knowledge and images that originate in an individual’s brain that are transferred by speech to the brain of others
cranial capacity
the volume of the brain case of the skull
endocranical cast
a cast of the inside of the brain case
cheek teeth
the premolars and molars
cusps
points on a tooth
insectivores
animals that eat primarily insects; also members of the mammalian order insectivora
frugivores
animals that eat primarily fruits
folivores
animals that eat leaves
omnivores
animals that eat a variety of different kinds of food
dental formula
2:1:2:3
dental arcade
the tooth row as seen from above
diastema
a space between teeth
sectorial premolar
unicusped first lower premolar with a shearing edge
Y-5 pattern
pattern found on molars with 5 cusps, separated by grooves, reminiscent of the letter Y
simian shelf
a bony buttress on the inner surface of the foremost part of the ape mandible, functioning to reinforce the mandible
chin
a bony projection of the lower border that arises on the side of the skull and inserts on the jaw
temporalis
a muscle of chewing that arises on the side of the skull and is used for chewing, inserts on jaw
sagittal crest
ridge of bone along the midline of the to of the skull that serves for the attachment of the temporalis muscle
masseter
a muscle of chewing that arises on the zygomatic arch of the skill and inserts on the mandible
