Hominin Evolution

Question 1

Rift Valley Hypothesis

Answer 1

Divergence of African great apes and bipedal hominins (8-5 mya) Population divided by Rift Valley, East: bipedalism and West: quadrupedalism.

Question 2

Mosaic evolution

Answer 2

Different physiological systems evolve at different rates.

4. 4 mya: bipedalism
5. 0 mya: reduced canine, thick enamel
6. 5 mya: stone tools
7. 0 mya: bigger brains

Question 3

Ardipithecus ramidis

Answer 3

5.8-4.4 mya. East Africa, Ethiopia. White and azfaw. Primitive features: ape-like jaw, thin enamel molars. Derived features: position of foramen magnum and non-weight bearing forelimb.

Question 4

Australopithecus anamensis

Answer 4

4.2-4.1 mya. Found by leaky clan in Lake Turkana, Kenya. Primitive features: sexual dimorphism (can indicate absence of monogamy) and small cranial capacity (400-500cc). Derived features: thick enamel and bipedal (as seen in tibia and patella).

Question 5

Australopithecus afarensis

Answer 5

4.0-3.0 mya. Primitive features: prognathic face, sectorial premolars, long arms, canine diastema, post orbital constriction, sexual dimorphism, small cranial capacity (350-500cc) Derived features: partial bipedal adaptations i.e. shape of femur, pelvis, and big toe. Lucy found by Donald Johansen in Hadar, Afar Region, Ethiopia.

Question 6

Australopithecus africanus

Answer 6

3.0-2.3 mya. Primitive features: sloping forehead and low brow ridges. Derived features: no canine diastema, less prognathic, reduced canines, anterior pillars, parabolic dental arcade (more human-like). “Taung Child”, found by Raymond Dart in Taung, South Africa.

Question 7

Raymond Dart

Answer 7

First to coin the term, “Australopithecus”. Originated the thought of “killer ape”, which implied that early hominids used tools to hurt each other, but was eventually refuted.

Question 8

Robinson’s dietary hypothesis

Answer 8

Gracile: generalized omnivore and Robust: specialized vegetarian. Each had teeth specialized for their respective diet.

Question 9

Paranthropus robustus

Answer 9

1.9-1.5 mya. Discovered in South Africa. Primitive features: Sagittal crest and large molars. Derived features: anterior pillars, flaring zygomatics, supraorbital torus, and large temporalis muscle. Discovered by Robert Broom.

Question 10

Paranthropus boisei

Answer 10

2.2-1.4 mya. East Africa. P. robust on steroids. Massive molars, Sagittal crest, nuchal crest, flaring zygomatics, and sexual dimorphism. Zinj, found in Olduvai Gorge by Mary Leaky.

Question 11

Genus homo

Answer 11

Larger brain (600cc and above), reduced postorbital constriction, foramen magnum farther forward, little facial prognathism, smaller teeth and jaws, and culture.

Question 12

Homo habilis

Answer 12

2.5-1.6 mya. Found in Southern Africa. Reduced supraorbital tori, incipient forehead, increased cranial capacity (612cc average), small body; long arms, gripping hands; curved phalanges. Oldest known use of tools.

Question 13

Oldowan tool tradition

Answer 13

2.6 mya, oldest known stone tools. Found in Olduvai Gorge, Ethiopia. Used by Homo habilis.

Question 14

Homo ergaster

Answer 14

African form, acheulean tools, more human-like, probable ancestor. Acheulean tool tradition. Controlled use of fire, first to migrate out of Africa, big game hunting.

Question 15

Homo erectus

Answer 15

1.8ma-200ka. Primitive traits: pronounced supraorbital torus, flat parietal bones, no chin, no humanoids prior to this point had chins. Derived features: Sagittal keel (smaller than sagittal crest), nuchal torsus, shoveled incisors on Asian and some African specimens, increased cranial capacity, larger bodies. Acheulean tool use.

Question 16

Acheulean tool tradition

Answer 16

Bifacial tools, tailored for different purposes; cleavers: process hides, meat; handaxes: cut wood, use as spears. Found in Africa, Middle East, and Europe. Commonly used by H. ergaster and H. heidelbergenis

Question 17

Homo floresiensis

Answer 17

95-17ka. Found in Flores island, Indonesia. Use of stone tools, dwarf descendant of H. erectus?

Question 18

Homo heidelbergensis

Answer 18

Transitional species between H. erectus and H. neanderthalensis. Europe by 800ka. Projecting nose and alveolar region (H. erectus traits). Receding chin and double arched brow ridges (H. neanderthalensis traits). Intermediate brain size. Acheulean tools up to 200ka, then developed levallois tools.

Question 19

Homo neanderthalensis

Answer 19

Generalized: 125-75ka. Middle East, Asia, East and Central Europe. Climate similar to present and less robust. Classical: Western Europe, 75-35ka, cold climate, cold specialized rugged bodies. Incipient forehead, double arched brow ridge, long and low cranial vault, occipital bum, wide nasal aperture, weakly developed chin, large cranial capacity, stout thick postcranial bones. Use of mousterian tools.

Question 20

Mousterian tool tradition

Answer 20

Refinement of levallois technique, 200-40ka, smaller tools, wider range of shapes and uses. Used by homo neanderthalensis

Question 21

Homo sapiens

Answer 21

High, vaulted cranium, 1325cc average, little brow ridge, small teeth and jaw regions, chin, less robust postcranial skeleton, first anatomically modern Homo sapiens in 190ka. Use of upper Paleolithic tools.

Question 22

Homo neanderthalensis innovations

Answer 22

Use of mousterian tool tradition, intentional burial, care for ill?, symbolic burial?, hunting close distance with spears.

Question 23

Upper Paleolithic tools

Answer 23

40-10ka. Marked by diversity and specialization. Blades twice as long as wide.

Question 24

Anatomically modern human innovations

Answer 24

Clothing, variety of hunting materials, symbolic burial, non-utilitarian objects, use of handmade shelters, artwork.