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Advanced Topics in Human Evolution > Exam 3 > Flashcards

Exam 3 Flashcards

1
Q

Which derived features are shared by modern humans and Homo ergaster? Which derived features are unique to H. ergaster?

A

Homo ergaster

Shared Derived Traits with modern humans:

  • Small, less prognathic face
  • Small teeth
  • Large brain (up to 1100 cc…)

Unique Derived Traits:

  • Large browridges
  • Occipital torus
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2
Q

What does the specimen KNM-WT 15000 tell us about H. ergaster?

A

KNM WT 15000: Nariokotome boy from Lake Turkana

Body Size and Shape

  • Skeleton indicates a tall, linear body of robust proportions.
  • 5½ to 6 feet tall; Long legs, narrow hips & shoulders, short arms, barrel shaped chest
  • This body build indicates that ergaster was committed to life on the ground and capable of running long distances
  • Heat dissipation through sweating

Development

  • faster life histories and shorter childhoods than previously thought. (He was 5ft tall at an estimated age of 8 or 9)

Vertebrae

  • Smaller spinal canal suggests less breathing control (Evidence against the existence of language in Homo ergaster)
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3
Q

What is a hand ax, and what did H. ergaster use it for? How do we know?

A

The hand ax is a mode 2 or “Ascheulean” tool. It is teardrop shaped created by removing flakes from a core. H. ergaster used it for several things, including:

  1. Butchering large animals
  2. Digging up tubers, burrowing animals, and water
  3. Stripping bark from trees to get the nutritious cambium layer underneath
  4. Hurling at prey animals
  5. dispensing flake tools
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4
Q

What evidence suggests that H. ergaster controlled fire?

A
  1. Burned seeds, wood, and flint artifacts found at the site of Gesher Benot Ya’aqov in Israel-These items represent a small fraction of material at the site, making it unlikely that they were burned in a wild fire.
  2. Burned bones, but these are less convincing
  3. In order to digest tubers, ergaster would have had to have cooked them first. Though we have no direct evidence, tubers would have been an important part of ergaster’s diet in order to support such a large brain.

…

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5
Q

What evidence suggests that H. ergaster ate significant amounts of meat? Is the evidence for H. ergaster carnivory better than that for the Oldowan hominins? Explain.

A
  1. intesitnal parasites
  2. symptoms of vitamin A poisoning in H. ergaster woman
  3. teeth made more for biting and tearing meat rather than chewing tough plant foods
  4. elephant bones show cut marks from stone tools
  5. hand axes seemed suitable for animal butchery
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6
Q

What are the main differences between H. ergaster and H. erectus? How would you explain the evolution of these differences?

A

H. erectus:

  • Face was more massive
  • walls of the cranium were thicker
  • cranium was lower and less domed
  • brow ridges are more pronounced and bar like
  • sides of the skull slope more steeply
  • occipital torus is more pronounced
  • sagittal keel is present
  • shorter and stockier postcranial features

Homo ergaster, who precedes erectus by 1mya, more closely resembles AMHs. Differences in features may have had to do with climate, and living conditions. erectus had to endure harsher environmental conditions.

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7
Q

Using present-day examples, describe the variation in climate during the Middle Pleistocene. Why is this variation important for understanding human evolution?

A

…

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8
Q

How is H. heidelbergensis different from H. erectus?

A

Derived features relative to H. erectus
1. Large brains
(1200-1300 cc)
2. Higher foreheads (but
still receding)
3. Rounded occipital
areas (less angular)
4. Double arched brow
ridges
5. Large nasal aperture
…

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9
Q

What important technological transition occurred about 300 kya? Why was it important?

A

Levalloise tool technique
When: 300 kya
Where: Africa then later W. Eurasia
What: Mode 3 Large, flakes knocked off of a prepared core

Evidence suggests that these tools were hafted (attached to a wooden handle); this is an important innovation as it increases the efficiency with which humans can apply force to stone tools

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10
Q

Explain why the fossils found at Sima de los Huesos are significant.

A

They are significant because they provide evidence that hominins in Europe began to develop a distinctive cranial morphology by 300 kya that they shared with the Neandertals

The large variable sample at Sima de los Huesos answered the question of whether or not a single variable population existed in Europe or many different populations. One single varialble population existed according to this evidence

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11
Q

What is the crural index? What does it measure? How does the crural index of the Neanderthals differ from that of modern tropical peoples?

A

The crural index is the ratio of the length of the shinbone (tibia) to the length of the thighbone (femur).

Neandertals have a lower crural index compared to modern tropical peoples. This means that their limbs were shorter; this was to keep them warm in a cold climate…

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12
Q

How did the Neanderthals differ from their contemporaries in Africa and eastern Asia?

A

…

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13
Q

What evidence suggests that western Eurasia was subjected to repeated invasions from Africa during the Middle Pleistocene?

A

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14
Q

What derived anatomical features distinguish modern humans from other hominins?

A

…

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15
Q

Explain why it is possible to make phylogenetic trees for mitochondrial DNA and the Y chromosome but not for other chromosomes. Why is it possible to make phylogenetic trees for individual genes on other chromosomes?

A

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16
Q

Explain why mitochondrial DNA and Y chromosome trees are consistent with the hypothesis that modern humans evolved in Africa and then later spread across the rest of the globe.

A

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17
Q

Suppose you were able to choose three fossils to extract DNA from and that your goal was to test the hypothesis that humans evolved in Africa. Which three would you pick? Explain why.

A

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18
Q

What does the sequencing of Neanderthal and Denisovan genomes tell us that we could learn from the study of fossils or the genomes of living peoples?

A

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19
Q

How do worldwide patterns of genetic variation support the idea that humans spread from Africa across Eurasia and Australia?

A

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20
Q

Describe what the archaeological record tells us about the pattern of human behavior across the world between 100 and 30 kya. What facts are widely accepted? Which are in dispute?

A

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21
Q

Describe the main differences between the tools of Upper Paleolithic peoples and those of their predecessors.

A

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22
Q

What evidence suggests that Upper Paleolithic peoples were better able to cope with their environments?

A

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23
Q

Homo habilis

List Dates Known, Distribution and Paleohabitat

A

Dates Known:

Distribution:

Paleohabitat

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24
Q

Homo habilis

List Brain Size, Key Features, and Importance

A

Brian Size:

Key Features:

Importance:

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25
Q

Homo rudolfensis

List Dates Known, Distribution, and Paleohabitat

A

Dates Known:

Distribution:

Paleohabitat:

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26
Q

Homo rudolfensis

List Brain Size, Key Features, and Importance

A

Brain Size:

Key Features:

Importance:

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27
Q

Supraorbital Torus (Shape/Size)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Supraorbital Torus (Shape/Size)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

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28
Q

Postorbital Constriction

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Postorbital Constriction

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

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29
Q

Contour of Occipital

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Contour of Occipital

H. erectus/ergaster: angular, but less so in ergaster

H. heidelbergensis (or “archaic” H. sapiens): rounded occipital areas (less angular)-variable

H. neanderthalensis: Occipital Bun

H. sapiens (modern): Limited development of occipital torus or bun

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30
Q

Sagittal/nuchal cresting or keeling

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Sagittal/nuchal cresting or keeling

H. erectus/ergaster: No sagittal crest, keel found in erectus only, pronounced occipital torus and nuchal crest?

H. heidelbergensis (or “archaic” H. sapiens): No sagittal crest or keel; pronounced occipital torus and nuchal crest*

H. neanderthalensis: no sagittal crest or keel, Occipital bun present

H. sapiens (modern): No sagittal crest or keeling, and no occipital bun, torus, or nuchal cresting

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31
Q

Forehead

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Forehead

H. erectus/ergaster: receding forehead

H. heidelbergensis (or “archaic” H. sapiens): Higher, but still receding

H. neanderthalensis: sloping forehead

H. sapiens (modern): High, flat

32
Q

Shape of Cranium (height to length)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Shape of Cranium (height to length)

H. erectus/ergaster: longer than wide, low set

H. heidelbergensis (or “archaic” H. sapiens): Long, low skull*

H. neanderthalensis: short height, long length-Large craniums that housed brains larger than those of AMHs.

H. sapiens (modern): Globular shaped, parallel sided cranial vault

33
Q

Size of Cranium Relative to Face

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Size of Cranium Relative to Face

H. erectus/ergaster: smaller cranium

H. heidelbergensis (or “archaic” H. sapiens): fairly large cranium (1200-1300cc): large face also*

H. neanderthalensis:

H. sapiens (modern): Large cranium, small face

34
Q

Prognathism

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Prognathism

H. erectus/ergaster: Alveolar? or Midfacial

H. heidelbergensis (or “archaic” H. sapiens): Aveolar prognathism

H. neanderthalensis:

H. sapiens (modern): No prognathism; flat face retracted under the skull

35
Q

Location of Maximum Skull Breadth

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Location of Maximum Skull Breadth

H. erectus/ergaster: Low, across mastoids creating an angular cranial vault

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern): across the parietals creating a parallel cranial vault

36
Q

Canine Fossa (yes/no)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Canine Fossa (yes/no)

H. erectus/ergaster: no

H. heidelbergensis (or “archaic” H. sapiens): no

H. neanderthalensis: no

H. sapiens (modern): yes

37
Q

Mastoid Process

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Mastoid Process

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern): Large, pyramidal shaped–sexually dimorphic

38
Q

Frontal Sinus (nasal aperture)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Frontal Sinus (nasal aperture)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens): large

H. neanderthalensis: large and very wide

H. sapiens (modern):

39
Q

Ascending Ramus

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Ascending Ramus

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens): large

H. neanderthalensis:

H. sapiens (modern):

40
Q

Molar Size Relative to Anterior Dentition

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Molar Size Relative to Anterior Dentition

H. erectus/ergaster: smaller molars than incisors, but both are smaller than that of australopiths and paranthropines

H. heidelbergensis (or “archaic” H. sapiens): small molars, shovel shaped incisors

H. neanderthalensis: Molars smaller than anterior dentition (large shovel-shaped incisors)

H. sapiens (modern): small teeth

41
Q

Molar Root Form

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Molar Root Form

H. erectus/ergaster: nontaurodont

H. heidelbergensis (or “archaic” H. sapiens): taurodont (fused pulpy roots)

H. neanderthalensis: taurodont (fused pulpy roots)-allow for more tooth wear.

H. sapiens (modern): nontaurodont- not as resistant to wearing, but more resistant to tooth loss.

42
Q

Retromolar Space (yes/no)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Retromolar Space (yes/ no)

H. erectus/ergaster: ?

H. heidelbergensis (or “archaic” H. sapiens): ?

H. neanderthalensis: yes

H. sapiens (modern): ?

43
Q

Chin (yes/no)

H. erectus/ergaster:

H. heidelbergensis (or “archaic” H. sapiens):

H. neanderthalensis:

H. sapiens (modern):

A

Chin “protruding mandible” (yes/no)

H. erectus/ergaster: no

H. heidelbergensis (or “archaic” H. sapiens): no

H. neanderthalensis: no

H. sapiens (modern): yes

44
Q

Heavy tooth wear is a typical feature of Neandertals and is also sometimes found in some modern human populations, such as the Inuit in the Arctic. What do you think caused such distinctive heavy tooth wear in the Neandertals?

A

Heavy tooth wear likely resulted from utilization of teeth as tools. It is suggested that Neandertals held meat with their teeth while using sharp tools to cut it from the bone.

45
Q

The chin is a unique derived trait in anatomically modern Homo sapiens. What do you think is the adaptive value of the chin?

A

I don’t think there is an adaptive value of the chin. However, it is possible that it is more of a sexually selected trait.

46
Q

Compare and contrast the Thorax of Homo neanderthalensis and modern Homo sapiens

A

H. neanderthalensis had a larger, hyper-barrel-shaped thorax–some say its conical (probably an adaptation to cold temperatures)

Modern H. Sapiens have a smaller, more cylindrical rib cage

47
Q

Compare and contrast the Pelvis of Homo neanderthalensis and modern Homo sapiens.

A

H. neanderthalensis had:

  • wider hips
  • larger, outward rotated hip joint
  • Longer, thinner, superior pubic ramus
  • …..
48
Q

Compare and contrast the Intermembral index (length of legs relative to arms) of Homo neanderthalensis and modern Homo sapiens

A

??? lower than ours and resembling Lapp population? but that is called the crural index…….It is lower in people who live in colder regions. high 60s-low 70s?

They have both a shorter tibia and forearm..(yet the femur and humerus are still relative to ours?)

49
Q

Compare and contrast the Limb bone length relative to thickness of Homo neanderthalensis and modern Homo sapiens.

A

Homo neanderthalensis has shorter, thicker limb bones than Homo sapien

50
Q

Compare and contrast the General description of skeleton, body shape of Homo neanderthalensis and modern Homo sapiens.

A

Homo neanderthalensis is shorter, and bulkier than modern Homo sapiens. H. neanderthalensis has larger joints, thicker bones, a larger cranium, more robust facial features, and broader hips, rib cage, and shoulders.

51
Q

What do you think the adaptive significance of the Neandertal postcranial morphology was?

A

The Neadertals probably had short robust bodies to better adapt to harsh, rapidly changing climates.
• Limb proportions correlated with mean annual temperatures (Inuits vs Nuer)

  • Allens’ rule - Organisms in cold climates tend to have shorter extremities
  • Bergmann’s rule – Endotherms tend to have bulkier bodies in cold temperature climates
52
Q

List 7 cranial traits of AMHS.

A
  1. Globular braincase
  2. Vertical forehead
  3. Canine fossa
  4. Pronounced chin
  5. Universal loss of robustness
  6. Small size of dental crowns
  7. Small face
53
Q

What would account for the small stature (~3.5 ft. tall) and small cranial capacity (380 cc) seen in the Homo floresiensis species?

A

Island dwarfism is one hypothesis. Another, less well accepted hypothesis is that it could have a pathology.

54
Q

Traditionally the genus Homo was defined as a hominin with a larger brain, tool use, first use of fire, butchery/preparation of meat, etc. This definition is problematic because there is a wide range of brain sizes known for this genus and paleontologists cannot prove that Homo was the first hominin that used tools or fire.

What are some better defining characteristics? (List 6)

A
  1. small, less prognathic face
  2. reduced postorbital constriction
  3. More rounded braincase
  4. Small teeth, with narrower tooth crowns
  5. more parabolic dental arcade, and reduced length of the molar tooth row, reduced jaw musculature
  6. More anteriorly positioned foramen magnum
55
Q

The 6 defining features of Homo might be adaptations related to changing lifestyles from that of earlier hominins (e.g. the Australopiths). What are some of these lifestyle changes?

A
  • Processing food with tools led to reduction in tooth size and jaw musculature
  • ???
56
Q

At this station:

  • Homo habilis*-OH 7 mandible; OH 24 cranium- pictures From Lucy to Language
  • Paranthropus boisei*– OH 5 cast
  • Australopithecus afarensis*– cast
  1. Compare the Homo habilis specimens from Olduvai to
    * Paranthropus boisei*, also from Olduvai. How do they differ in both cranial and dental features?
A

Comared to Paranthropus boisei, Homo habilis has:

  • a more rounded braincase
  • reduced post-orbital constriction
  • reduced lower facial prognathism
  • a more anteriorly situated foramen magnum
  • Narrower tooth crowns, particularly in the lower premolars
  • reduction in length of the molar tooth row
  • a more parabolic dental arcade
57
Q

At this station:

  • Homo habilis*-OH 7 mandible; OH 24 cranium- pictures From Lucy to Language
  • Paranthropus boisei*– OH 5 cast
  • Australopithecus afarensis*– cast
  1. Homo and Paranthropus lineages emerged during the same time period, 3-2 million years ago. In some cases they are found at the same sites. How might two species of apes live in the same location at the same time? Hint: look at their teeth. What might they have
    been eating?
A

Paranthropus boisei had an enormous jaw with massive chewing muscles and huge back teeth that helped grind down tough-to-chew but more abundant plant foods such as nuts, roots and tubers (largely underground vegetables, the potato being a modern example).

Homo habilis, on the other hand, had small teeth and jaw muscles, which made it difficult digest the touch-to-chew plant foods. Homo habilis’ diet consisted primarily of meat, which was easy for them digest, and high in calories and nutrients. They did not hunt for the meat, however, they scavenged for it.

58
Q

At this station:

  • Homo habilis*-OH 7 mandible; OH 24 cranium- pictures From Lucy to Language
  • Paranthropus boisei*– OH 5 cast
  • Australopithecus afarensis*– cast
  1. Compare OH 24 (Homo habilis) to the skull of
    * Australopithecus afarensis*. Name two similarities (sympleisiomorphies or primitive features that demonstrate they are both hominins) and two differences (autapomorphies or features that demonstrate they should be placed in separate genera).
A

Sympleisiomorphies: 1) sloping chin 2) anteriorly situated foramen magnum

Autopomorphies: 1) more rounded braincase 2) small teeth

59
Q

The single largest sample of Homo habilis comes from Koobi Fora in ______________ . Brain size in this sample of H. habilis ranges from less than _____ to ____ . Some of the faces are small and projecting and others are large and flatter. The lower jaws also vary in size and shape. All of this variation has been considered sexual dimorphism by some researchers, but others have stressed that the cranial features are so different that ___________________.

A

northern Kenya

500CC; 800CC

two distinct species must be present

60
Q

At this station you will find KNM-ER 1470 and KNM-ER 1813 which are both dated around 1.8-1.9MYA. KNM-ER 1813 represents Homo habilis and KNM-ER 1470 is
considered by many to be a different species—Homo rudolfensis (or even in a different genus, Kenyanthropus rudolfensis). Describe how these specimens (species) are different in the following ways:

  1. Braincase / cranial capacity:
  2. Length of face:
  3. Supraorbital torus (browridge):
  4. Cheek teeth (1470 teeth not preserved so compare alveoli (roots) of premolars):
A

Braincase/Cranial Capacity

rudolfensis: larger brain case

habilis: smaller brain case

Length of Face

rudolfensis: broad flat face longer than habilis’ face

habilis: small face, not very flat

Supraorbital torus (browridge)

rudolfensis: slight brow ridge

habilus: stronger, curved brow ridge

Cheek Teeth (compare alveoli (roots) of premolars)

rudolfensis: larger molars and tall cheekbones

habilis: smaller molars

61
Q

How do you know that the small size of KNM-1813 (Homo habilis) is not due to immaturity?

A

The third molar has erupted and appears to have been worn down.

62
Q

How can you tell that the KNM-ER 1813 and KNM-ER 1470 specimens were found at the same fossil site and how can you tell where that is?

A

KNM stands for Kenyan National Museum; it is where all fossils that are found in Kenya are kept. ER stands for East Rudolfensis, meaning that the fossils were found on the Eastern side of Lake Turkana.

63
Q

What are some similarities that you see that would support the argument that the KNM-ER 1813 and KNM-ER 1470 fossils represent one sexually dimorphic species?

A

The differences between the two specimens appear to be mere size differences, and they were from the same time period in the same region.

64
Q

Compare KNM-ER 1470 to the cast of Kenyanthropus playtyops. What similarities do you observe that may justify lumping these two specimens at the generic level?

A

…

65
Q

One of the many lingering questions and debates is which of the Australopiths gave rise to the genus Homo
and did the genus evolve in East or South Africa? We read some of the new articles about Au. sediba this week and read about how the researchers on this team argue that this species gave rise to the genus Homo.

  1. What are some of the features that Berger and colleagues use to argue this point (describe at least 2)?
A

crowns of their teeth, relatively long thumb capable of human-like precision grip, orbitofrontal shape and organization more like a human brain? ….

66
Q

Compare the cast of Au. sediba to the casts of H. habilis
and Au. Africanus. Do you see any traits where you think Au. sediba is more Homo-like than Au. Africanus is?

A

Sediba has a more rounded braincase and less postorbital constriction than africanus…..

67
Q

What are the Au. sediba fossils dated to?

What, if any, problems are there with this date and the proposed Homo ancestry?

A

1.5 mya? …

This date indicates that Au. sediba was still living when the Homo emerged. If they co-existed, sediba can be Homo’s ancestor

68
Q

KNM-WT 15000 “_____________” (cranium showed in picture) is the most complete skeleton of any early hominin discovered to date. This individual died in early adolescence and provided important information about Homo ergaster/erectus life history as well as body size and proportions. His estimated age at death is 8–9 (depending on estimate used), indicating ______ development than in modern humans. His projected height, weight, and skeletal proportions are very similar to modern equatorial Africans.

Overall, this skeleton demonstrates that hominins by at least ____ MYA had departed from the ape-like australopithecine body plan of our early evolution and were rapidly approaching the body and brain size that characterize modern humans. KNM-WT 15000 is considered Homo ergaster by many researchers.

A
  • Nariokotome or Tukana Boy
  • faster
  • 1.6
69
Q

Compare the femora of Australopithecus afarensis, Homo ergaster/erectus (from an adult female), and a modern human (compare the overall size, thickness, etc.).

a.Describe the similarities/differences.

A

Similarities: modern humans is longer and erectus is second longest? The all indicate bipedalism?

Differences:

70
Q
  1. Is the femur of Homo ergaster/erectus more like the A. afarensis femur or more like modern humans?
  2. What is the significance of this? What does this say about the evolution of bipedalism?
A
  1. The Homo ergaster/erectus femur is more like the modern human femur.
  2. Homo ergaster/erectus were bipedal, and capable of walking and running long distances.
71
Q

The type specimens of H. erectus come from China and Java, and these have been argued to differ from early primitive African forms in having larger, flatter, and angular braincases, thicker skull walls, thicker browridges, etc. These differences justify placing the more primitive African forms in Homo ____________.

A

Ergaster

72
Q

Compare the African KNM-ER 3733 (H. ergaster) dated to about 1.8 MYA with the reconstruction of the Chinese form (H. erectus) dated to 300-600 KYA.

  1. Locate the parts of the cranial buttressing system in these fossils:
    a. None of these specimens have what we consider a pronounced sagittal crest, but some have sagittal keeling. Which of the specimens has the most pronounced sagittal keeling (also note the parasagittal depressions on the side of the keel)?
    b. Do you see any other differences between the African and Asian specimens?
A
  1. Parts of Buttressing System:
  • H. ergaster (African)-
    • Thinner cranial bones than H. erectus
    • Prominent Supraorbital torus (brow ridges), but thinner than in H. erectus
    • occipital torus present but less robust than in H. erectus
    • No sagittal keel
    • Postorbital constriction
    • Higher cranial vault than H. erectus, but low compared to AMHs
  • H. erectus (Chinese)-
    • A thick-boned, robust skull that is longer than wide
    • Angularity of skull enhanced by prominent supraorbital torus (brow ridge)
    • Thickened angular torus and occipital torus
    • Sagittal keel
    • Postorbital constriction
  1. a. H. erectus has the most pronounced sagittal keeling, and thus parasagittal depressions; b. differences listed in part 1. Overall, H. ergaster is more gracile than H. erectus.
73
Q

Name two cranial features that “stick out” in the African KNM-ER 3733 (H. ergaster) dated to about 1.8 MYA and the reconstruction of the Chinese form (H. erectus) dated to 300-600 KYA specimens.

A

H. ergaster:

  1. sadfsd
  2. occipital torus

H. erectus:

  1. Sagittal keel
  2. robust brow ridges
74
Q

Here are samples of Oldowan (associated initially with
H. habilis) and Acheulean (associated initially with H. ergaster/erectus) tool technologies.

  1. Which is which and how could you tell? In what specific ways do Acheulean tools differ from Olduwan tools?
A
  1. Tool A is an Oldowan tool, and Tool B is an Acheulean tool. Tool B is nice and thin, seems like it would be easier to hold, easier to transport, and has more of a sharp cutting edge. Tool A is thicker, less defined, and has more dull edges.
  • Oldowan tools consist of cores (river cobbles) or source material from which flakes are removed by striking with a hammerstone. The flakes or small fragments are extremely sharp and useful in butchering meat or slicing through animal hide.
  • Acheulean tools are standardized, convenient to transport, easier to hold and use without fatigue, and they maintain a sharp edge.
75
Q

What cognitive advancement is reflected in the Acheulean tools relative to Olduwan?

A

Acheulean tools are standardized, indicating that the hominids who made them had the ability to form a plan or mental template, and to foresee the consequences of their actions.

76
Q

See the table that you filled out from the last page of the worksheet for Lab 4

A

NOW!

77
Q

What 3 primary conclusions we can make about modern Homo sapiens based on patterns of genetic variation within living people and genetic material extracted from fossils?

A
  1. modern humans evolved in Africa between 200 and 90 kya.
  2. modern humans outside of Africa are all descended from a small population that left Africa 60 kya
  3. there was a small amount of interbreeding between the expanding modern human populations and the hominis already living in Eurasia including the Neandertals and the Denisovans

Advanced Topics in Human Evolution (3 decks)

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