Chapter 10

Question 0

A paleontologist examines a hominin skeleton that is found in a mixture of ancient stone and fossilized bone. The find best illustrates a ?

Answer 0

Breccia

Question 1

Which description best illustrates a dental feature of hominins rather than apes?

Answer 1

The presence of a thick enamel.

Thick enamel is a hallmark of hominin teeth. Page 247

Question 2

How does the CP3 honing complex change in hominins?

Answer 2

It disappears.

Question 3

Why are scientists unsure of whether “Sahelanthropus tchadensis” should be considered a hominin or not?

Answer 3

It has human like features such as smaller canine teeth, but also has apelike features such as a U-shaped dental arcade.

Question 4

Statement that best describes the genus “Australopithecus”?

Answer 4

“Australopithecus” can be described as small-bodied and small-brained biped with moderately prognathic faces and both human and apelike dental features.

Question 5

Hominin cohabitation?

Answer 5

At some times in history, more than one species of hominin shared a single habitat.

Question 6

Where is the foramen magnum located in a human?

Answer 6

Underneath the skull.

Because humans are bipeds. Page 240

Question 7

Humans and chimpanzees diverged from our last common ancestor about how many million years ago?

Answer 7

6 million years ago.

Question 8

Endocast

Answer 8

A replica of the interior of the skull, which can shed light on the brain of the fossilized animal.

Question 9

Anatomical feature that suggests specialized adaptation for chewing tough foods?

Answer 9

A flaring of the zygomatic arch.

Robust Australopithecus. Page 264

Question 10

What is one way in which the study of fossils in South Africa is different from the study of fossils in East Africa?

Answer 10

East Africa fossils can be dated using argon-argon techniques whereas South Africa fossils cannot.

Question 11

How did cohabitation if early hominins species most likely affect the diets if these species?

Answer 11

The different species probably developed different dietary habits to avoid direct competition.

Question 12

Cervical vertebrae

Answer 12

The seven neck vertebrae

Question 13

Coccyx

Answer 13

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

Question 14

Compound temporoncuchal crest.

Answer 14

Bony crest at the back of the skull formed when an enlarged temporalis muscle approaches enlarged neck muscles. Present in apes and Au.afarensis

Question 15

CP3 honing complex

Answer 15

Combination if canine and first premolar teeth that form a self-sharpening apparatus. Disappears as the hominin lineage progresses.

Question 16

Cranial crests

Answer 16

Bony ridges on the skull to which muscles attach.

Question 17

Femoral condyles

Answer 17

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

Question 18

Foramen magnum

Answer 18

Hole in the occipital bone through which the spinal cord connects to the brain.
Located underneath the skull in humans because they are bipeds.

Question 19

Gluteal muscles

Answer 19

Gluteus Maximus
Gluteus medius
Gluteus minimus
The muscles of walking, which have undergone radical realignment in habitual bipeds.

Question 20

Hominin or hominid

Answer 20

A member of the primate family Hominidae. Distinguished by bipedal posture.

Question 21

Innominate bones (os coxae)

Answer 21

Pair of bones that compose the lateral parts of the pelvis.

Each made up of 3 bones that fuse during adolescence. The ischium. The pubis. The sacrum.

Question 22

Pubis

Answer 22

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

Question 23

Ischium

Answer 23

Portion of the innominate that forms the bony underpinning of the rump. It is the bone we sit on.

Question 24

Sacrum

Answer 24

The fused vertebrae that forms the back of the pelvis.

Question 25

Sagittal crest

Answer 25

Bony crest running lengthwise down the center of the cranium of the parietal bones; for attachment of the temporalis muscles.

Question 26

Tarsals

Answer 26

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

Question 27

Thoracic vertebrae

Answer 27

The 12 vertebrae of the thorax that hold the ribs.

Question 28

Vertebral column

Answer 28

The column if bones and cartilaginous disks that houses the spinal cord and provides structural support and flexibility to the body. A spine that is S-shaped and has larger vertebrae at the bottom than at the top needed for bipedalism.

Question 29

Early hominin most recently discovered?

Answer 29

"Australopithecus sediba"(1.97-1.78 mya) Discovered in 2010.

Question 30

"Au. afarensis"

Answer 30

(3.9-2.9 mya) Cranial and dental features in between living apes and modern humans. Bipedal but also showed some skeletal features of arboreality (living in trees). Page 254

Question 31

"Au. africanus"

Answer 31

(3.5- 2.0 mya)

Question 32

"Au. kadabba"

Answer 32

(5.8-5.2 mya)

Question 33

"Au. ramidus"

Answer 33

(4.4 mya)

Question 34

"Au. robustus" (Paranthropus)

Answer 34

Known for their unique adaptations for chewing tough foods. Flared zygomatic arch.