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Human Evolution > Homo > Flashcards

Homo Flashcards

1
Q

What new evidence has come to light regarding the age of the oldest Homo Sapiens fossils in Africa

A

found in Omo-Kibish and Herto, Ethiopia, dating of deposites from an eruption of the Shala volcano, which overlies the fossils, shows a new minimum age to be 233+/-22kya

(Vidal et al. 2022)

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2
Q

Describe the juvenile pelvis of H naledi

A

showed incipient development of features expressed inadultH. nalediilia. The proportional height of the Lesedi ilium was within the rangeof human juveniles between 4–11 years of age

australopith-like iliac blade morphology

expanded auricular surface more similar to humans

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3
Q

Where have Homo erectus fossils been found

A

Europe (AKA Homo antecessor) between 1.6 and 0.5Mya

West Asia (georgicus) 2-1.6mya

Africa (ergaster) 2-0.7mya

E Asia - 2-0.4mya

SE Asia - 1.5-0.2mya

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4
Q

Who first defined H erectus

What was important about this fossil

A

Dubois based on fossil from Java

Large cc (950cc) from 0.5mya

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5
Q

How long could erectus have lived in Java

A

Oldest found in Sangiran ad is 1.6-1.3Ma
Youngest could be as young as 0.1Ma
Survived for 1.5My

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6
Q

What is the problem with fossils found in Sangiran

A

Sangiran hard to date cos often found and moved by farmers

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7
Q

How does erectus molars differ from habilis molars

A

in erectus M3 is reduced compared to the very large M3 of habilis

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8
Q

Describe the evolutionary trends in Javan Homo erectus morphology.

A

Early – many primitive features, large teeth, narrow dental arcade
Later – larger in cc, frontal less flat, AP extended cranial base, short temporal muscle attachment

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9
Q

How old is the Ngandong erectus material?

key features?

A

found along river so can be hard to date - Riza 2020 suggests ~110kya
CC:1132cc
Flat horiztontal orbital torus

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10
Q

Dubois found 2 femora and a calotte in Java which were all claimed to be erectus. Why is this doubted?

A

Trinil I femur is much closer to a late Pleistocene H. sapiens morphology (therefore not used in erectus analyses)

Trinil II is likely contemporaneous with the calotte and both are erectus

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11
Q

What is Meganthropus

A 
 Dubois’ paratype of 
Pithecanthropus erectus from 1891
 NOT HOMININ BUT APE(S), probably 
related to Lufengpithecus, and 
possibly including Gigantopithecus
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12
Q

Give some typical erectus features of the fossils in Sangiran

A

Large SO torus with supratoral sulcus

Long receding forehead

bregmatic eminence

Large face, with reduced alveolar prognathism

Salient nasal bones

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13
Q

Where were key erectus fossils found in 1920s and 30s

How old?

A

China

The fossils from Zhoukoudian, China were lost during WWII

 Estimated age: 780 – 400 Ka

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14
Q

How does the Zhoukoudian erectus material differ from that of Java? (3)

A
  • Size: 915-1225cc (upper is almost sapiens)
  • Forehead: not receding – arched and curved – allometry?
  • Sagittal keel: much less pronounced
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15
Q

Why is the material from Hexian interesting?

A

V young – 400ky

Affinities to early java material – more similar to older erectus – survival of more primitive erectus in some parts of china

Some dental (EDJ) affinities to early African Homo

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16
Q

What is the temporal pattern of Homo erectus occupation of Asia? What questions does it raise?

A

Early Pleistocene has fossils and stone tools but then large temporal gap – repopulation?
Fossils in Africa from ~2mya classed as erectus but that species is based off Dubois’ skull cap from ~0.5mya in SE Asia – surely there had been selective pressures etc – problems here

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17
Q

What is the type specimen of ergaster

A

KNM-ER 992 from Koobi Fora (1.7ma)

mandible with no retromolar space and a slender corpus

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18
Q

What is the retromolar space

A

The retromolar space or retromolar gap is a space at the rear of the mandible, between the back of the last molar and the anterior edge of the ascending ramus where it crosses the alveolar margin.

This gap is generally small or absent in modern humans, but it was more often present in Neanderthals

Not seen in ergaster but is in erectus and earlier hominins

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19
Q

What is the importance of the Turkana boy

A

first humanlike narrow skeleton (90%) complete

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20
Q

How old was the Turkana boy

A

8‐9 years old [developmental stage equivalent to a human 12 year old child]

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21
Q

What were the key features of the Turkana boy (4)

A

Resembles a very robust modern human from
the neck down

 Brachial and humero‐femoral index in the
modern human range

 Barrel‐shaped rib‐cage

Narrow bi-iliac breadth

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22
Q

What is interesting about KNM-ER 42700?

A

East African H erectus

Young adult – not fully fused synchondrosis
Mosaic – projecting glabella, distinct keels, no occipital torus, rounded back, max length at lambda, modern arrangement: tympanic bones orientated coronally(?) while petrous bones are sagittally

Thin bones in skull while erectus has thick bones – no prominent SO torus or trigones – outside range of erectus? But not habilis either

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23
Q

What was the range of cc in E African erectus

A

from 691 cc (KNM‐ER 42700) to 1067 cc (OH 9)

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24
Q

How does E African occipital compare to that of non-African erectus

A

 Occipital: less angular than in non‐African Homo erectus (except OH9)

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25
Q

What is important about the Buia and Bouri skulls?

A

Very different skulls but contemporaneous (1mya)

Bouri has the most features shared with later Middle Pleistocene hominins

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26
Q

Regardless of whether we classify them as populations of the same species or separate species, what can we learn from the mosaics of traits seen in different groups of “erectus”?

A

Tall, slender body, with narrow shoulders, barrel‐shaped rib‐cage, narrow pelvis, legs longer than arms

 Larger cranial capacity than Homo habilis

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27
Q

Why is StW 53 interesting

A

has been classified as Homo, Au. africanus, and P. robustus

existed 1.78‐1.49 Ma
• Small cc
• Large teeth
• M3 > M2

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28
Q

What is the temporal distribution of African H erectus

A

Homo ergaster

2-0.8mya

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29
Q

What evidence is there of regional erectus fossils being different species

A

morphometric studies show:
The frontal bone of African “erectus” fossils is different

The parietal bones of African “erectus” fossils are different

The occipital bone of African “erectus” is similar to Chinese “erectus”, but not Javanese erectus fossils

Different skull bones are different in ‘erectus’ from different regions – different trajectories?

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30
Q

Compare erectus and ergaster (8)

A 
 ergaster has thinner cranial bones
 No sagittal keel
 No bregmatic eminence
 More pronounced supratoral sulcus
 Less developed supraorbital torus
 Less developed occipital torus
 Slender mandibles
 Relatively gracile TMJ
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31
Q

What does Homo erectus sensu lato include

A
  • All post‐habiline hominins prior to major brain enlargement in the Middle Pleistocene
  • Widely distributed in Asia and Africa
  • 2.0 – 0.1 Ma
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32
Q

What is Homo erectus sensu stricto

A

Javanese fossils only, perhaps
including East Asian remains
• >1.6 Ma – 0.1 Ma

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33
Q

What is H ergaster

A 
African lineage only
• Ancestral to H. erectus ?
• 2.0 – 1.0 Ma
• Less specialized features
• Very variable
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34
Q

What does a) the fossil evidence and b) lithic evidence suggest about when hominins first left Africa

A

a) Crania from Dmanisi, Georgia ~1.77Ma
Longgudong - >2.14ma?

b) Stone tools from Southern China 2.12Ma – only 17 artefacts
N India – 2.6Ma
Indication but not substantial but does suggest OoA 2-3ky earlier than fossils suggest

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35
Q

Who was the first hominin in Georgia
How long were they there

Did they have tools

What was the cranial capacity of these hominins

A

Homo georgicus (Georgian Homo erectus)

1.77 Ma (fossils)
• ~ 100,000 years of occupation of the site
(from ~1.85 Ma)

 Oldowan artefacts (Mode 1)

Small cranial capacity: 546 cc to 730 cc - lots of variety
• D4500: 546 cc (EQ ~ Australopithecus)

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36
Q

What can we infer about the behaviour of Homo georgicus (Georgian Homo erectus)

A

toothless individual 9D3444/D3900) would not have had easy access to food so must have been looked after

o Paramasticatory use of anterior dentition of D2600 – teeth worn labially – used to hold objects

o Lateral extension of body of mandible near molars – typical of early hominins absent in ergaster and later Homo

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37
Q

What was the face shape of H georgicus

Zygomatics?

A

Prognathic – could be part of developmental process as D4500 has most pronounced cf D2282 and D2700 which are both not fully developed (adolescent and juvenile respectively) - same can be said for the supraorbital torus

Flared zygomatics cf not flaring in erectus

Less angular head – more similar to ergaster

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38
Q

What did Lordkipanidze et al. (2013) suggest about taxic diversity of early Homo, based on Dmanisi?

A

Early homo out of Africa were very diverse and should be considered as a single highly variable species

This implies the existence of a single evolving lineage of early Homo, with phylogeographic continuity across continents.

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39
Q
  1. What might the link between A.L. 666, SK847, and Dmanisi?
A

Similar shape of subnasal clavus and maxillary pillars and angle of zygomatics which are slightly flared – possible association
This would put Dmanisi material as descent from fossils in Africa that predate erectus or ergaster

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40
Q

Which species has the most similar body proportions to the Dmanisi postcrania

A

H sapiens

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41
Q

What are the derived traits of Homo georgicus (Georgian Homo erectus)

A

• Biomechanically efficient locomotion, both for long‐range walking and energy
storage/return during running
 Leg length and morphology similar to modern humans
 Adducted hallux and plantar arch

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42
Q

Homo georgicus (Georgian Homo erectus) is a mosaic. What are the primitive features

A 
Retention of primitive characters not seen in later hominins
 More medial orientation of the foot
 Absence of humeral torsion
 Small body size
 Low encephalisation quotient (EQ)
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43
Q

Why may the Dmanisi hominins not be a single species

A 
Significant differences between individuals
• Significantly larger size variation 
than in humans
• Significantly larger shape 
variation that any extant ape 
species

 Established early in ontogeny
 Independent of size or sexual dimorphism
 Not synchronic deposition of fossils
 2 different palaeodemes?

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44
Q

a) What is the oldest hominin fossil out of Africa

b) Oldest sites with stone tools or cut‐marks on fauna

A

a) Longgudong, China (>2.14 Ma? controversial)
Otherwise, Dmanisi, Georgia, W Asia 1.77 Ma

b) Quranwala, Siwaliks, N India 2.6 Ma (controversial)

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45
Q

When was there faunal exchange 1.5-2.5mya

A

 2.6 – 2.5 Ma: Afro‐Eurasian faunal exchange
Africa->Eurasia: Giraffa, Struthio
Eurasia->N. Africa: Ursus
Eurasia->Sub-Saharan Africa: equus

 1.8 – 1.6 Ma: important Afro‐Eurasian faunal exchange (mostly out of Africa) - carnivores, primates, hippos
 From Eurasia to Africa: wolves

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46
Q

What is the significance of the faunal exchange 1.5-2.5mya

A

• 1.8-1.6 Ma: out of Africa mostly – main point of dispersal

Why does it matter? – hippos are v water dependent like humans so not only was there a corridor but also fresh water was available

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47
Q

What might the relationship between hominins and carnivores have been? Why does this matter for dispersals?

A

Used same range bc humans acted as scavengers utilizing the carcasses left behind by giant carnivores

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48
Q

Why might the earlier dispersal (2.5mya) only have been a limited dispersal?

A

Were exchanges of fauna but limited – no archaeology

Did not colonise Maghreb(?) (Western N Africa) and Nile was not strong corridor of water to support the dispersal

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49
Q

Why do researchers suggest that ATD6-69 might be the LCA of Neanderthals and modern humans?

A

Sima del Elephante - maxilla of child 1.2Ma – LCA of neanderthals – v controversial
Intersection of Zygoma and maxillary has sharp depression – typical of early humans
Why in spain? – recurrent connection with Africa through middle east? – maybe just part of erectus diversity

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50
Q

What do proteomes tell us about Homo antecessor?

A

Antecessor’s ancient proteomic data (small sample size) suggests it is the sister group of sapiens

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51
Q

Describe Model 1 of the dispersals of early Homo out of Africa

A

MODEL 1 – one single dispersal early (2.5‐2.2 Ma)
Early dispersal of early Homo; tethered to highlands? (stone; water)
Giving rise to Homo georgicus and a population ancestral to Homo erectus in eastern Asia

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52
Q

Describe Model 2a of the dispersals of early Homo out of Africa

A

Main dispersal at 19‐1.8 Ma
[either no early dispersal, or extinction of those very early Asian populations]
Dispersal of early Homo, giving rise to Homo georgicus (and later European pops., including H antecessor) and ancestor of
Homo erectus in East Asia

1.6 ‐ 0.8 Ma EMPT
Regional isolation in Asia
Expansion in Europe

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53
Q

When did H erectus live?

What happened during this time to this species?

A

2-0.1mya

it regionalised, acquiring local differences due to different pressure in each local environment, as well as due to founder effects and drift

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54
Q

Many researchers argue that erectus differences should be recognized taxonomically, and several local populations have been given species names:

A

ergaster to the African fossils

georgicus to the Dmanisi fossils

antecessor to the fossils from Spain

erectus to the Javan and Chinese populations

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55
Q

What are the key features of erectus’ skull

what ergaster does not have

A

thick cranial bones (not ergaster), angled occipital (variable), with strong
superstructures, including a sagittal keel (not ergaster) and a pronounced
supraorbital torus

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56
Q

With which early members of Homo did the erectus group overlap temporally? And what about members of other hominin genera?

A

Rudolfensis and habilis

Boisei

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57
Q

How does the cranial capacity of erectus vary

A

546-1250cc

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58
Q

What are the body proportions of erectus

A

1.3-1.7m
Modern proportions
KNM-WT – share proportions of most recent Homo and v different from habilis and Lucy

Erectus achieved greater stature earlier on than modern humans

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59
Q

What can we learn from the hominin footprints from Ileret, East Turkana?

A

1.5mya

Modern human functional anatomy – adapted hallux, medial longitudinal arch and medial weight transfer before push-off – size and distance between are consistent with stature of erectus
Fully committed to terrestiality

60
Q

Describe the arboreality of H ergaster

A

Homo ergaster fully committed to life on the ground

 Adapted to long‐distance running

 Useful in long‐distance scavenging and hunting in open country

61
Q

Is there sex dimorphism of erectus

A

If all not habilis = erectus then there is dimorphism – size

62
Q

Describe the life history pacing of Homo erectus. How do we know?

A

Looking at microstructure of enamel can give age – KNM-WT15000 was 8yo (consistent with dental eruption and fusion of epiphyses) – same as chimp trajectory – stark contrast to human child (closer to a 10-15yo human child’s anatomy) – erectus still growing more like an ape than human but there is a shift to slowing of LHS

63
Q

How does the human brain grow after birth

A

Humans have sustained brain growth after birth – unique to humans (6 years after birth at foetal growth rate – fast and demanding)

64
Q

How long ago do we have evidence of humans eating meat

A

Efficiency through hunting, not just scavenging [cut‐marks on elephant bones at
Olorgesailie (~1 Ma) with no underlying carnivore marks]

65
Q

When is there evidence of controlled use of fire

A

Swartkrans, South Africa: burnt bones
in 20 levels (1.5‐1.0 Ma)
• Koobi Fora, East Turkana, Kenya (1.5 Ma)

66
Q

How long ago have we got evidence of fireside entertainment

A

15kya

plaquettes from France with ancient paintings as well as colouring suggesting they were placed by a fire

when AI was used to see what they would have looked like by the fire originally they moved

Needham (2022)

67
Q

What were key factors contributing to erectus’ LHS (2)

What did this mean for its LHS

A

 lived in a complex environment – broader diet, larger ranges, competition with carnivores
 was encephalised – larger brain to body size

 developed more slowly than australopithecines but still faster than modern humans
 had a reduced childhood in comparison to humans ‐ short period of learning
 Bigger at an earlier chronological age than humans

68
Q

Homo erectus  developed more slowly than australopithecines but still faster than modern humans
 had a reduced childhood in comparison to humans ‐ short period of learning
 Bigger at an earlier chronological age than humans

What allowed this to occur

A

high energy diet using cooking and hunting

69
Q

What was the importance of erectus being bigger at an earlier chronological age than humans

A

protect against predation

Erectus juveniles were energetically independent and may have contributed to the group - high energy environment

70
Q

How much more energy could cooked starch contribute to hominin diet?

What else did fire allow hominins to access?

How did the introduction of cooking affect time

A

> 30%

honey -> >100c more

> 4hr/day saved on chewing

71
Q

What is the temporal trend in encephalization in Homo erectus?

A

Australopithecines constant trend of encephalization, with increase in early homo, and progressive trend towards larger size from erectus
Complete pelvis of female suggests they could give birth to big headed babies – but not as big as humans

Different proportions of brain areas

72
Q

Comment on the cognition of Homo erectus.

A

Different cognition from other hominins – increased carnivory and archaeological sites
Care of old and young
Cannibalism?
Trinil, java – geometric scratches on shell from 0.54mya - notation/ symbolism

Problem solving in complex environment – wider ranges, new predators, new competitors, climate change

73
Q

What is the evidence for erectus’ care for elderly

A

toothless skull of individual >40y/o

Dmanisi 1.77mya

74
Q

What is the evidence for hominin cannibalism

A

cut marks on skulls
1.2mya in Spain
H antecessor

75
Q 
What were the conditions and constraints on H erectus becoming a fully terrestrial 
carnivore ape, with 
opportunistic range 
expansions and 
dispersals
A 
CONDITIONS: 
carnivory and stone‐
tool making; slender, 
narrow body with 
longer legs than arms
CONSTRAINTS: 
Permanent 
freshwater and raw 
materials for stone‐
tool manufacture; 
relatively fast growth
76
Q 
What were the causes and consequences on H erectus becoming a fully terrestrial 
carnivore ape, with 
opportunistic range 
expansions and 
dispersals
A 
CAUSES: 
Increased competition due 
to niche reduction as a 
result of climate change 
and inter‐specific hominin 
diversity; competition with 
carnivores

CONSEQUENCES:
Adaptive radiation of Homo
with new ancestral body plan
and large body size achieved
early in development, leading to geographical diversification, increased genetic variance, and new subsistence strategy (social predators) and a dependence on technology and high energy diet. These
consequences set the adaptive platform through which all descendant populations benefitted from slower growth, encephalisation, and greater social cognition, leading to convergent evolutionary trends

77
Q

Is cooking still important

A

Even now across the world it is v hard to find anyone who has not cooked in the last 3-4 waking hours
Evening meal is universally cooked
hard to thrive on raw food
Cooking helps more than eating meat

78
Q

What happens if modern humans don’t cook food

A

As raw food increases to 100% - amenorrhea even with domesticated food and there is no shortage of food – won’t be able to have baby – we are adapted to eat cooked food

Starch – when cooked v similar to just eating glucose – more productive – does this fit with digestive anatomy – different processes in large and small intestine

79
Q

How much honey to great apes eat

A

None
hunter gatherers eat lots – humans use cooking – honey guides Apis honey, reducing time looking for honey from 8 to 3 hours
Evolved behavior not learnt from parents
- ancient adaptation to high glycaemic load

80
Q

5 things we have learnt from ancient genomes about the evolution of hominins in the last 1 million years?

A
  1. LCA of modern humans – 280kya
  2. 300kya is when sapiens separated
  3. Neanderthals and denisovans separated 450kya
  4. Sapiens separated from N and D 750-550kya
  5. 950-750kya when N/D/Sapiens separated from other hominins
81
Q

What happened 800kya

Why did this happen

A

MAJOR shift in climate (early to middle Pleistocene)

Long‐term cooling of sea‐surface temperatures
• Increase in amplitude of glacial cycles
• Shift from 41,000 to 100,000 year mode

Due to changes in Earth’s orbit -

82
Q

What is eccentricity and how does this affect climate

A

Eccentricity refers to the shape of the Earth’s orbit around the sun, and its
natural variation from more or less elliptical.

When the orbit is more elliptical, Earth receives greater variation in energy from the sun throughout the year than when the orbit is circular

83
Q

What is obliquity

A

Obliquity refers to the axial tilt of the Earth, or angle between the axis and plane of rotation.

Earth’s obliquity oscillates between 22.1o and 24.5o on a 41,000 year cycle.

Obliquity is what causes the seasons.

84
Q

What is the precession of equinoxes

Why is it important

A

The precession of the equinoxes (the shift between a hemisphere being tilted away from or toward the sun) occurs on a 19,000‐23,000 year cycle.

Precession cycles define the timing and intensity of solar insolation.

85
Q

What are the 2 configurations of Milankovitch cycles

A

Glacial/Ice‐Growth configuration

Interglacial/Ice‐Melt configuration

86
Q

Describe the Interglacial/Ice‐Melt configuration of the Milankovitch cycles

A

High eccentricity (elliptical orbit)
 High obliquity (more seasonal contrast)
 Small Earth‐Sun distance in summer (more
ice melting, increased heat absorption)

EFFECT: warmer summers, cooler winters

87
Q

Describe the glacial configuration of the Milankovitch cycles

A

 Low eccentricity (circular orbit)
 Low obliquity (tilt)
 Large Earth‐Sun distance in summer (no ice
melting, increased heat reflection)

EFFECT: less seasonal contrast

88
Q

What happened to Climate change in the Early‐to‐Middle Pleistocene Transition (EMPT)

A

• Long‐term cooling of sea‐surface temperatures
• Increase in amplitude of glacial cycles
• Shift from 41,000 (dominated by obliquity) to 100,000 year (dominated by eccentricity) mode
• Shift to asymmetric glacial cycles: short warm and long cold phases with abrupt endings
(terminations)

89
Q

What are glacials/interglacials defined by?

A

Glacials/Interglacials are defined by insolation at 65 degrees N latitude

90
Q

What are “terminations”?

A

When a glacial cycle ends in an abrupt increase in temperatures

91
Q

What happened to the length of temperature cycles after the EMPT

A

Shift from 41,000 to 100,000 yr long cycles

92
Q

How do processional cycles affect the Sahara

A

• Hydrological response to eccentricity and its interaction with precessional cycles (ie, how the
amount of precipitation in the tropics [monsoons] relates to the interaction between the shape of
the Earth’s orbit around the sun and the timing and intensity of solar insolation at high latitudes)

  • EFFECT: amplification or dampening of tropical monsoons
    1. eccentricity minima: weak monsoons at precessional timescales, increased aridity in East Africa, “Yellow Sahara” phase
    1. eccentricity maxima: increase in tropical climate variability at 100,000 and 400,000 yr cycles [independent of continental ice volume] with alternating strongest and weakest monsoons [alternating “Green Sahara” and “Desert Sahara” phases]
93
Q

When was the most recent Green Sahara event

A

12 to 6kya – when monsoons are at max for short window of time – rained so much animals could cross and live there

94
Q

Do inferred population splits tend to happen in dry or wet Sahara episodes?

A

s-D-N split from other hominins was during dry spell – moment of fragmentation of African populations – sufficiently long to keep populations separate to maintain different evolutionary trajectories

s from N and D – intense wet episode with green Sahara – during contact between sub-Saharan and northern Africa

N from D during dry – fragmentation event again

S and other hominin again in aridity then followed by green Sahara event

95
Q

Why is the Middle Pleistocene a “muddle”?

A
  • Processes: different dispersals – lots of different interactions – complex
  • Analytical techniques: not enough organic stuff to date properly
96
Q

Describe African fossil record from EMPT

A

KNM-OL 45500 – one of smallest hominin fossils ever found - + the other two v different crania (Buia and Bouri)

97
Q

When/ where are Buia and Bouri from

A

erectus/ergaster crania

Buia
• Eritrea
• ~ 1.0 Myr
• 750‐800 cc

Bouri, Middle Awash, Ethiopia
~ 1.0 Myr
995 cc

98
Q

What are 2 of the oldest fossils of hiedelbergensis

A

fragmentary cranium from Algeria ~800‐700 Ka ?

Casablanca
• Morocco
• 600‐400 ?
• Cranial fragment

99
Q

Give the primitive and derived traits of the hiedelbergensis fossils found in North Africa from 400kya

A 
Primitive traits:
• ~930 cc
• Low position of max breadth
• Pronounced supramastoid crest
• Bregmatic eminence
Derived traits:
• Frontal convexity
• Rounded temporal squama
• Vertical wall of parietals
• Pattern of meningeal vessels
100
Q

What is the oldest evidence of heidelbergensis in South Africa?

What is the cc

A

> 600 Ka

1225 cc

101
Q

What the flora and fauna like in South Africa ~600kya

A

Over 50 different spp of mammals, as well as birds, reptiles and amphibians.

Vegetation: included bush and trees, at least around the spring‐fed water
bodies, and more open bush and grass than at present, but appears to have been fynbos.

102
Q

Describe the features of heidelbergensis in East Africa ~600kya

A

Bodo
Middle Awash, Ethiopia
630 Kya

  • ~1100 cc
  • broad, massive face
  • extremely broad nose (the largest of any Pleistocene hominin)
  • thick supraorbital torus

CUT MARKS - prehistoric defleshing/ cannibalism?

103
Q

When did Lahr place the LCA for humans and Neanderthals

A

virtually reconstructed 3 different scenarios and found one placing vLCA 700kya is most consistent with fossil record

suggest an Afro-European ancestral population in the Middle Pleistocene (Homo heidelbergensis sensu lato)

104
Q

What is the importance of Gesher Benot Ya’aqov (GBY)

Israel

A

800‐700 Ka
• ~ 100 Ka use of area, lacustrine
• Rich Acheulean industry

rich evidence of fire – points to north Africa dispersal

105
Q

Did heidelbergensis make it to the UK

A

Boxgrove - found a large tibia suggested to be heidelbergensis from 500kya

106
Q

Give a key heidelbergensis fossil from Greece

A 
Petralona
? [700‐200 Ka]
• 1220 cc
 ~90o angle nuchal/occipital planes
• very large, orthognatic face
• prominent transverse torus
107
Q

Describe the cranium from Ceprano Italy from ~400kya

A

Homo heidelbergensis ?
430‐385 Ka
• 1185 cc - large

  • Very pronounced, tall supraorbital torus
  • Angled occipital
  • No sagittal keeling
  • Very thick bones
  • No derived Neanderthal character

Nothing here preempts Neanderthals
Could have had different populations with different amounts of derived features around this time

108
Q

Give the cave in Spain that holds lots of individuals

Who are these individuals

A

Sima de los Huesos

> 29 individuals at bottom of cave shaft
More women than men – bar 1 child most are teens/young adults
Died simultaneously
May individuals from single population
together with bones of cave bears and 1 handaxe

109
Q

What is the cc of the crania in the Sima de los Huesos

Any other important bones?

A

from 1125cc to 1390cc (larger is average for model humans)

Complete pelvis – much more flared than modern – very tall -165-170cm
Radiating fractures in crania – interpersonal conflict
handaxe
child with serious pathology - care?

110
Q

Have heidelbergensis fossils been found in France?

A

yes in Arago from 400kya

smaller cc: 1166cc

111
Q

What is the importance of Steinheim

A

Partial cranium – not very derived and has small cc (~900cc) – survivor ship of an older population which was present before N arrived

112
Q

What is heidelbergensis broadly

A

Heidelbergensis has become associated with any middle Pleistocene specimen in Europe that fits the description of being very robust with teeth similar to the type specimen from Mauer

113
Q

Were Homo heidelbergensis hunters ?

A

• Large numbers of stone tools associated with large animal carcasses:
elephants, rhinos, buffalo, etc.
•‘Butchery’ sites, such as Torralba & Ambrona, Spain
•Hunting weapons – Schöningen spears, Germany
•Hunting & Scavenging ?v

114
Q

Is there any suggestion heidelbergensis could control fire

A 
Schöningen, Germany
 ~ 400 Kyr
 2‐3 m long wooden spears
 Tip hardened by fire
 Associated with butchered horse carcass

Temp would be so cold they would have needed control of fire and needed high energy diet

115
Q

When was the Neanderthal/ Denisovan split

A

450kya

116
Q

What are the possible Homo erectus remains found to be younger than Neanderthal/ Denisovan split in E Asia

A

Jinniushan - female (from pelvis) with 1400cc

117
Q

What is important about fossils found in Xujiayao

A

from 160‐220 Kya

Mosaic:
• Different from archaic and recent humans
• Some features shared with Neanderthals, but not exclusive
• Some primitive traits shared with older eastern Asian fossils

118
Q

Give some evidence for populational interactions across Eurasia during the late Middle and early Late Pleistocene.

A

fossils from Linjing; 105-125kya

overall cranial shape, and especially the combination of the wide cranial base and low neurocranial vault, indicates a pattern of continuity with the earlier, Middle Pleistocene eastern Eurasian humans. Yet the presence of two distinctive Neandertal features—one (iniac and nuchal morphology) unknown among earlier eastern crania, and the other (labyrinthine proportions) evident in only one similarly aged eastern Eurasian fossil

119
Q

What is the importance of fossils in Xiahe, Tibet

A

> 160kya mandible

proteomics indicate it is Denisovan

indicate that archaic hominins occupied the Tibetan Plateau in the Middle Pleistocene epoch and successfully adapted to high-altitude hypoxic environments long before the regional arrival of modern Homo sapiens.

120
Q

Why does a fossil found in Taiwan highlight Pleistocene Asian diversity

A

unexpectedly late survival (younger than 450 but most likely 190–10kya) of robust, apparently primitive dentognathic morphology in the periphery of the continent

cannot be simply explained by clinal geographic variation of Homo erectus between northern China and Java, and suggests survival of multiple evolutionary lineages among archaic hominins before the arrival of modern humans in the region.

121
Q

When was LCA of modern humans in Africa

A

280kya

122
Q

Which fossils may be attributed to Homo rhodesiensis

A

Ndutu
400kya, 1100cc

Eliye Springs, Kenya
350kya, 1300-1450cc, Chronic anemia in childhood?

both have no sagittal keeling and relatively rounded occipital

Kabwe, Zambia - Type specimen of Homo rhodesiensis
299kya
Bregmatic eminence like erectus so primitive but present 300kya

123
Q

What could Homo rhodesiensis be part of

A

Homo heidelbergensis

124
Q

What is Homo helmei

A

found in Florisbad, South Africa
• 259 ± 35 Ka

• Large orthognatic face
• Large orbits and nose
• Large supraorbital ridges, but not 
shaped like a torus
• Very broad

(Homo aff. Sapiens)

125
Q

What is important about fossils found in Jebel Irhoud

A

315kya

Very small face with many modern features – has beginnings of a chin

126
Q

Who is a possible contender for LCA of mid-Pleistocene hominins

A

Bodo, dating to 630 ka, shares features with later old world mid Pleistocene hominins pointing to that connectivity in time

127
Q

In pre-aDNA days, where did researchers place Homo heidelbergensis on a hominin phylogeny?

What did Krause et al. (2010), using aDNA, add to the phylogeny—and where on the phylogeny?

A

Believed to emerge out of Africa from erectus bottleneck
Bottleneck in heidelbergensis led to sapiens and a distinct bottleneck led to neanderthals who then died off

• Heidelbergensis as LCA between Neanderthals and sapiens
OR
• Rhodesiensis and heidelbergensis as sister taxa stemming from antecessor with the former leading to sapiens and the latter leading to Neanderthals
OR
• Rhodesiensis being LCA of neanderthals and sapiens with no hiedelbergensis

Separate branch of ghost hominin – Denisovan

128
Q

What other hominin genes does the Denisovan genome contain

A

0.0% modern human
• 0.5% Neanderthal (*** HLA)
• 0.5‐8% ANCIENT (Homo erectus?)

129
Q

Denisovan genes in what other hominins:

A

0.0% Denisovan in Neanderthals
• 0.2% Denisovan in modern Han Chinese, Dai of S China, Karitiana of Brasil
• ~4‐6 % Denisovan genes in PNG, Australia, Philippine Negritos

130
Q

What is strange about the genetic material from Sima de los Huesos (Homo heidelbergensis)?

A

mtDNA Clustered with Denisovans

Nuclear genome: Neanderthal ancestor

131
Q

What is the likely temporal range of the LCA of humans, N and D

A

900-700kya

extreme aridity

132
Q

What was the Competitive context (other hominins?) for the LCA of humans, Neanderthals, and Denisovans

A

north vs sub Saharan? Homo antecessor? At least co-existed with another hominin
No fitting fossil has been found

133
Q

When is genetic split of
a) humans x NEA/DEN

b) genetic split NEA x DEN

Where did each occur

A

a) 750-550kya (within Africa)

b) 450kya (in Eurasia)

134
Q

When did the African ancestors of NEA‐DEN exist?

What climatic event does this fit with?

How does this meet archaeological findings (2)

What does this suggest

A

Probably between 650‐550 Ka

Minor “Green Sahara” events between 600‐500 Ka

 Consistent with introduction of Acheulean into Europe
 Consistent with the similarities observed between African and European Middle
Pleistocene fossils
 Implies the rich, African looking (full of cleavers, absent in Europe) Acheulean at GBY
was an earlier (limited?) dispersal

135
Q
  1. Is a gene coalescence date the same as a population separation?
A

not necessarily

136
Q

Model 1 suggests Neanderthal and Denisovan lineages separate during the during out of Africa event. What does this imply?

What is the problem with this

A

the split would date to date of dispersal out of Africa , and implies that the LCA was not Eurasian, but African, and lived between 700-450 Ka.

Too late to fit fossil record
Achulean would have to be earlier dispersal

137
Q

What is model 1 of the LCA of Neanderthals and Denisovans

A

: Neanderthal and Denisovan lineages separate during the process of out‐of‐Africa
dispersal
 time of split = time of dispersal out of Africa
 Implies that ancestor of NEA‐DEN lived in Africa between 700 and 450 Ka
 Too late to fit the fossil record? Earliest ages (Ceprano, Sima) ~430 Ka; Petralona?
 Implies the rich, African looking (full of cleavers, absent in Europe) Acheulean at GBY
was an earlier (limited?) dispersal

138
Q

Give model 1 of the LCA of Neanderthals and Denisovans in the context of the related climatic events

A

900‐700 Ka
AFRICAN MEGADROUGHT
Populations fragment and
differentiate

700‐450 Ka
Populations expand
“Green Sahara” events

450 Ka
Dispersal out of Africa
and split between NEA
and DEN

139
Q

What is model 2 of the LCA of Neanderthals and Denisovans

A

: Neanderthal and Denisovan lineages separate in Eurasia some time after the out
of Africa dispersal
 time of dispersal out of Africa much before split NEA x DEN
 Implies that ancestor of NEA‐DEN lived somewhere in Eurasia between 700 and 450 Ka
 What Eurasian fossils match the LCA of NEA & DEN?
 Earliest “non‐erectus” fossils in China ~350 Ka – where were the Denisovans before?

140
Q

What is the problem with the idea of an Eurasian LCA of Neanderthals and Denisovans?

A

No Eurasia fossis match this

Earliest non-erectus fossils are ~350kya – where were Denisovans before this?

141
Q

Why could one argue that the non-erectus (e.g. Jinniushan, Dali) fossils in China are Denisovans?

A

temporal overlap between Homo erectus and a different hominin in China who shares
similarities with contemporary western Eurasian populations and Neanderthals

0.5‐8% ANCIENT genes in Denisovans - Perhaps this ancient gene is Asian erectus and occurred as these two populations met when the west entered china

142
Q

Why was the evolutionary geography complex in the middle Pleistocene

A

Afro‐Eurasian dispersal(s)
 Euro‐East Asian dispersal(s) – Siberian corridor
 Regionalisation of evolutionary trajectories

143
Q

Who were the hominins in Africa and Eurasia in the Middle Pleistocene

A

Homo heidelbergensis, Homo rhodesiensis (?) & Denisovans
 Acheulean in Europe and Africa
 Complex behaviours

144
Q

Who were the hominins in China in the Middle Pleistocene

A

late survivorship of H. erectus (~400 Kyr)
 China: co‐existence of H. erectus with a heidelbergensis‐related
hominin, presumably related to Denisovans

145
Q

Who were the hominins in SE Asia in the Middle Pleistocene

A

: late survivorship of H. erectus (~100 Kyr)
 Denisovans in Southeast Asia?
 Co‐existence with Homo floresiensis – the hobbit

Human Evolution (16 decks)

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