Homo

Question 1

The Descent of Man (1871)

Answer 1

Darwin predicted that fossils of human ancestors would be found in Africa

Question 2

The Natural History of Creation in 1866/1868

Answer 2

Haeckel predicted that fossils of human ancestors would be found in Asia

Question 3

History of Discovery of fossil Homo

Answer 3

Eugene Dubois was a Dutch naturalist and paleontologist influenced by the ideas of Darwin and Haeckel

Question 4

Who was the first scientist to go looking for fossil evidence of human evolution?

Answer 4

Eugene Dubois
- discovered the Trinil skullcap in 1891 on the banks of the Solo River (Java)
- Dubois first named the discovered fossils Anthropopithecus, then changed to Pithecanthropus erectus
(Got the genus name from Haeckel, who used it to describe a theoretical “missing link”
- These fossils were later grouped with other Asian fossils into the species Homo erectus by Ernst Mayr

Question 5

The discovery of Australopithecus

Answer 5

• Fossils first discovered at Taungs lime quarry in South Africa
  (Australopithecus means “Southern Ape”)
• described by Raymond Dart in 1925
• Generic holotype: Taung Child

~ Ape-sized brain
~ Small canines
~ Anteriorly positioned foramen magnum=bipedal

Question 6

Louis and Mary Leakey

Answer 6

• Began archaeological and paleoanthropological excavations in Eastern Africa (Kenya and Tanzania) in the late 1920s

Question 7

Olduvai Gorge, Tanzania

Answer 7

Primarily archaeology until Mary finds “Zinj” in 1959
- Louis did not believe Zinj was the tool manufacturer

Question 8

Original Diagnosis of Homo habilis (Leakey, Tobias, and Napier, 1964)

Answer 8

• reduced post canine teeth
• well-developed speech areas of the brain
• presence of precision grip
• tool use

Question 9

H. habilis

Answer 9

Generally thought of as the oldest and most primitive species in the genus Homo but taxonomy has been problematic since the beginning

Question 10

Characteristics of the genus Homo

Answer 10

Homo is a Plio-Pleistocene genus of hominin historically defined by:
- relatively larger brain
- loss of prognathism
- derived limb proportions
- larger stature
- less dimorphism
- smaller molars and premolars
- smaller, more delicately built faces
- parabolic palate (NOT U-shaped)
- Associated with stone tool technology

Oldest fossils assigned to the genus Homo are about 3 Ma

Question 11

Parabolic dental arcade

Answer 11

• more human-like jaws and teeth
• derived
• teeth are arranged in a shorter, wider arch

Question 12

Why do species in the genus Homo have more delicately built faces and less prognathic faces?

Answer 12

Reduced subnasal prognathism is related to the change in tooth and jaw structure

Question 13

Cranial capacity of Homo

Answer 13

Larger cranial capacities than australopiths

• low as 600 cc or as high as 800 cc

Question 14

The appearance of Homo and the robust australopiths coincide (roughly) with environmental change

Answer 14

• beginning ca. 3 Ma, cooler, drier and with greater variability in climate
• vegetation regime shifts in Turkana Basin at about 2.5 Ma
  (more open, grassy habitats)
  (less dense forest, trees clumped and patchy; woodland)
• rise of the robust australopiths and appearance of Homo around this time

Question 15

How could robust australopiths and Homo coexist at the same time in the same place?

Answer 15

Niche partitioning

Question 16

Stone tool types

Answer 16

• Manuports
• Anvils
• Hammerstone
• Core
• Flake

Question 17

Core

Answer 17

Must be of appropriate material, appropriate size

Question 18

Flake

Answer 18

• Must have a good striking platform
• Must strike at proper angle
• conchoidal fracture and percussive bulb created when done correctly

Question 19

The Oldowan Lithic Industry

Answer 19

Until recently, this was the oldest and simplest stone tool technology
- few flakes from unprepared core
- choppers
- mostly unifacial

> 2.5 - 1.76 Ma

Even at old sites, the flaking is well-executed

Question 20

Oldowan tools were probably used for a variety of applications

Answer 20

• processing plant material
• extracting marrow (scavenging)
• cutting meat (scavenging or maybe hunting)

Question 21

Cutmarked bones show good evidence for being exploited for food by hominins

Answer 21

Recovered from Hata Mbr of Bouri Fm in 2.5 Ma
- cut marks in meat-rich areas
- percussive marks on marrow-rich shafts
- no stone tools found in concentration or in situ in Hata Mbr
- Paleoenvironment: low energy lake margin

Question 22

Some flaking may have evolved earlier than the Oldowan

Answer 22

The Lomekwian industry was recently proposed to be earlier than the Oldowan (possibly australopiths)

Question 23

We do not know very much about body proportions in very earliest Homo

Answer 23

• Most paleoanthropologists think this partial skeleton (OH 62) belongs to Homo habilis
  (palate and teeth are Homo)
• some features of this specimen resemble australopiths a bit
• Smaller body size
• Relatively long forearms
• Curved fingers

Question 24

A lot of what we know about early Homo body proportions come from the Homo erectus partial skeleton “Nariokotome Boy”

Answer 24

• larger-bodied (over 100 lbs and over 5 ft)
• human-like proportions of arms and legs (shortened forearms and elongated femora and tibiae)
• shoulder like modern humans

Question 25

Homo erectus

Answer 25

Oldest hominin species to be found outside Africa

Question 26

The Acheulean Industry

Answer 26

• beginning 1.76 Ma Acheulean appears
• defined by the presence of handaxes, bifacial flaking, and shaped objects
• more carcasses than at Oldowan sites (more success at scavenging?)
• raw material transport

Question 27

Hunting or scavenging?

Answer 27

Cutmarks superimposed over tooth marks

Use wear analysis: Primary use is processing vegetal materials plant foods

Question 28

Hand axes

Answer 28

Highly variable in size and raw material, BUT shape persists for over a million years

Question 29

Oldowan

Answer 29

2.5 Ma

Question 30

Acheulean

Answer 30

1.8 Ma