Chapter 10

Question 1

vertebral column

Answer 1

The column of bones and cartilag-inous disks that houses the spinal cord and provides structural sup-port and flexibility to the body.

Question 2

cervical vertebrae

Answer 2

The seven neck vertebrae.

Question 3

thoracic vertebrae

Answer 3

The twelve vertebrae of the thorax that hold the ribs. l

Question 4

lumbar vertebrae

Answer 4

The five vertebrae of the lower back.

Question 5

sacrum

Answer 5

The fused vertebrae that form the back of the pelvis.

Question 6

coccyx

Answer 6

The fused tail vertebrae that are very small in humans and apes.

Question 7

foramen magnum

Answer 7

Hole in the occipital bone through which the spinal cord connects to the brain.

Question 8

innominate bones (os coxae)

Answer 8

The pair of bones that compose the lateral parts of the pelvis; each innominate is made up of three bones that fuse during adolescence.

Question 9

ischium

Answer 9

Portion of the innominate bone that forms the bony underpinning of the rump.

Question 10

ilium

Answer 10

The blade of the innominate to which gluteal muscles attach.

Question 11

pubis

Answer 11

Portion of the innominate that forms the anterior part of the birth canal.

Question 12

gluteal muscles

Answer 12

Gluteus maximus, medius, and minimus, the muscles of walking, which have undergone radical realignment in habitual bipeds.

Question 13

femoral condyles

Answer 13

The enlarged inferior end of the femur that forms the top of the knee joint.

Question 14

tarsals

Answer 14

Foot bones that form the ankle and part of the arches of the foot

Question 15

. metatarsals

Answer 15

Five foot bones that join the tarsals to the toes and form a portion of the longitudinal arch of the foot

Question 16

CP3 honing complex

Answer 16

Combination of canine and first premolar teeth that forms a self-sharpening apparatus.

Question 17

type specimen

Answer 17

According to the laws of zoologi-cal nomenclature, the anatomical reference specimen for the species definition.

Question 18

cranial crests

Answer 18

Bony ridges on the skull to which muscles attach.

Question 19

sagittal crest

Answer 19

Bony crest running lengthwise down the center of the cranium on the parietal bones; for the attach-ment of the temporalis muscles.

Question 20

compound temporonuchal crest

Answer 20

Bony crest at the back of the skull formed when an enlarged tempo-ralis muscle approaches enlarged neck (nuchal) muscles; present in apes and Au. afarensis.

Question 21

breccia

Answer 21

Cement-like matrix of fossilized rock and bone. Many important South African early humans have been found in breccias.

Question 22

endocast

Answer 22

A replica (or cast) of the inter-nal surface of the braincase that reflects the impressions made by the brain on the skull walls. Natural endocasts are formed as sediments fill the braincase.

Question 23

postorbital constriction

Answer 23

The pinching-in of the cranium just behind the orbits where the temporalis muscle sits. Little constriction indicates a large brain and small muscle; great constriction indicates a large muscle, as in the robust groups of Australopithecus (Paranthropus).

Question 24

zygomatic arch

Answer 24

The bony arch formed by the zygomatic (cheek) bone and the temporal bone of the skull.

Question 25

Australopithecus species

Answer 25

small-bodied, small-brained, bipedal African apes with both primitive and derived characters

Question 26

Au. anamensis (4.2–3.9 mya)

Answer 26

This early form is likely ancestral to Au. afarensis. * Primitive characters include a shallow, U-shaped palate and large anterior teeth.
* Derived characters include somewhat smaller canine crown, thick enamel, and adaptations to bipedalism.

Question 27

Miocene~timeframe

Answer 27

(10–5.5 million years ago)