The Last Ape Standing It is therefore probable that Africa was formerly inhabited by extinct - PowerPoint Presentation

Slide1

The Last Ape StandingSlide2

It is therefore probable that Africa was formerly inhabited by extinct apes closely allied to the gorilla and chimpanzee: and as these two species are now man’s nearest allies, it is somewhat more probable that our early progenitors lived on the African continent than elsewhere.

-Darwin (1871)

The Descent of ManSlide3

Mt-DNA Primate TreeSlide4

Our Living Sisters

Pan

Gorilla

http://www.mnh.si.edu/anthro/humanorigins/ha/a_tree.htmlSlide5

Living Asian Apes

Gibbon (

Hyalobates

)

Orangutan (

Pongo

)Slide6

Apes in the PrimatesSlide7

Features that distinguish the

Hominins from other

living apes

Bipedal Locomotion

Loss of fur

Reduced dentitionEnlargement of the brainVocal communicationSlide8

Possible origins of bipedal locomotion

Figure 1 from Richmond, B. G., D. R. Begun, and D. S. Strait. 2001. Origin of human

bipedalism

: The knuckle-walking hypothesis revisited. Yearbook of Physical Anthropology. 44:70-105.Slide9

Bipedalism

Freed the hands and allowed more manipulative capabilities

Led to a higher thermoregulatory efficiency

Widened feeding potential

Reduced predation pressures

Was more energetically efficient mode of locomotionSlide10
Slide11

Oldest evidence of bipedalism

Australopithecus afarensis

footprints from

Laetoli

, Tanzania in volcanic ash following a rainfall around 3.4

mya

.Slide12

Footprint experiment

(Raichlen et al. 2010)

A. Normal gait in sand (

H.sapiens

)

B. Bent-knee, bent-hip gait in sand (similar to walk of apes)C. Footprint from

Laetoli

, Tanzania (similar to H. sapiens)Slide13

Neoteny

An explanation for:

Nakedness

Large Brain Size

Reduced DentitionSlide14

The Neotenic

Apes

Morphometry of the human skull changes little from fetus to mature adultSlide15

Hair loss and liceSlide16

Phylogeny of some living primates and their liceSlide17

Tales of the Lice

Human head louse vs

chimp louse (how long ago we diverged) ~6-7MYA

Human head louse

vs human body louse (how long ago we began to wear clothes) ~50-100KYAHuman pubic louse

vs gorilla body louse (how long ago we began to lose fur to patches of hair) ~3-4MYASlide18

Large Brain

Potts 2011

Navarette

et al. 2011Slide19

Reduced dentition

The lower jaw of modern humans is quite weak compared to the other apes. Our chin is the result of a small shelf of bone that provides some added strength to a relatively weak jaw.Slide20

Vocal communication

http://www.voice.northwestern.edu/VOICEBOX/Larynx.htm

Lower larynx

Fox P2 gene

The genetic basis for vocal communication seems to lie, in part, with the Fox P2 gene, which is shared with Neanderthals. The physical apparatus includes the larynx, and resonating chambers (mouth and nasal passages. Slide21

Vocal Communication

The larynx of a chimpanzee is so high in the back of the throat that it can drink and breathe at the same time. Ours is so low that we run the risk of choking every time we swallow. Clearly, the more subtle vocal communication afforded by the added range of sounds generated by humans through a larger resonating chamber outweighs the risks. Slide22

PBS NOVASlide23

Proconsul

Likely a sister to the apes with a mix of ape-monkey characters

14-23

MYA

AfricaSlide24

Dryopithecus

Early ape

15-9

MYA

Africa, EurasiaSlide25

Ardipithecus

Africa

Brain ~300-350cc

120 (f) cm tall

50 (f) kg

~6.0 – 4.2

MYASlide26

Miocene Epoch

23-5.3

MYA

Epoch of ape radiation (>100 species of apes in the latter part of the Miocene)

They ranged though Africa, Europe, and Asia

The end of the Miocene saw the separation between the African Apes (chimpanzees,

bonobos

, and gorillas) and the

Hominin

Apes

Africa moved northward and formed the Mediterranean Sea, which dried out multiple times.

Data from NASA,

USGS

, NOAASlide27

Pliocene Epoch

5.3-2.5

MYA

Epoch of bipedal ape radiation.

They ranged though Africa

Gracile

and robust lines

Pliocene relatively warm

Data from NASA,

USGS

, NOAASlide28

Human Phylogeny

The Smithsonian Institution

Museum of Natural History

http://www.mnh.si.edu/anthro/humanorigins/ha/a_tree.htmlSlide29

Human Phylogeny

Dembo et al. (2016)Slide30
Slide31

(A) 

Pan troglodytes

, chimpanzee, modern

(B)

Australopithecus

africanus, 2.6 My(C)

Australopithecus

africanu

s

, 2.5 My

(D) 

Homo habilis

, 1.9 My(E) Homo habilis, 1.8 My

(F) Homo rudolfensis, 1.8 My(G) 

Homo erectus, 1.75 My

(H) Homo ergaster (early 

H. erectus), 1.75 My(I) Homo heidelbergensis

,

300,000 - 125,000 y

(J)

Homo

neanderthalensis

, 70,000 y

(K)

Homo

neanderthalensis

, 60,000 y

(L)

Homo

neanderthalensis

, 45,000 y

(M)

Homo sapiens

, 30,000 y

(N) 

Homo sapiens

, modern

http://www.talkingorigins.com

Hominin

Series Slide32

Australopithecus

afarensis

Africa

Brain 375-550 cc

107 (f)-152 (m) cm tall

29 (f) – 42 (m) kg

~3.0-3.9

MYA

British Museum of Natural History and Smithsonian MuseumSlide33

Australopithecus africanus

Africa

Brain 420-500 cc

110 (f)-140 (m) cm tall

30 (f) - 41 (m) kg

~2.4-2.8

MYA

British Museum of Natural History and the Smithsonian MuseumSlide34

Paranthropus

robustus

Africa

Brain ~530cc

110 (f)-130 (m) cm tall

32 (f) – 40 (m) kg

~1.0 – 2.0

MYA

http://www.maropeng.co.za Slide35

Pleistocene Epoch

2.5-0.012

MYA

Appearance and radiation of

Homo

.

They ranged though Africa and emerged into the rest of the earth.

Global climates extremely unsettled and variable

Data from NASA,

USGS

, NOAASlide36

Homo habilis

http://macscience.files.wordpress.com

Africa

Brain ~500-800 cc

100 (f) – 135 (m) cm tall

32 (f) – 37 (m) kg

~1.44-2.3

MYASlide37

Olduwan stone tools in Ethiopia

2.6 -1.8

MYA

Chipped pebbles and choppers, usually lava

Likely made by

H.

habilisSlide38

Homo erectus

Africa, Eurasia

~Brain 750-1225 cc

145 (f) – 185 (m) cm tall

40 (f) – 68 (m) kg

~0.3-1.8

MYA

http://www.mnh.si.edu/anthro/humanorigins/ha/a_tree.htmlSlide39

Range of H. erectus

Evidence for controlled use of fire

Acheulean

tools (1.7-0.1

MYA

)

http://anthro.palomar.eduSlide40

Homo heidelbergensis

Africa, Eurasia

Brain ~1100-1400 cc

157 (f) - 175 (m) cm tall

51 (f) – 62 (m) kg

~0.2-0.6

MYA

Smithsonian InstitutionSlide41

Homo neanderthalensis

Eurasia

Brain ~1100-1400 cc

155 (f) – 164 (m) cm tall

54 (f) – 64 (m) kg

~0.03-0.3

MYA

Neanderthal MuseumSlide42

Range of the Neanderthals

http://www.rhesusnegative.netSlide43

Behaviors of H.

neanderthalensis

Scavengers and up close spear hunting of large animals (see Figure)

Relatively complex stone tools (Mousterian, see Figure)

Tools from wood, bone, tusks, and antlers

Evidence of burials and ceremonyPossible verbal communicationSlide44

Denisovans

Enigmatic group of archaic humans, sister group to Neanderthals, known only from a few bones and teeth. The genome has been sequenced.

Asia

50-400

kya

?Slide45

Range of Archaic HumansSlide46

Homo floresiensis

Asia (Indonesia)

Brain ~380-417 cc

~106 (f?) cm tall

30 (f?) kg

~

0.050-0.100

MYASlide47

Homo sapiens

Africa to all land surfaces

~1350 cc (975-1499)

US

ave

: 162 (f) – 175.8 (m) cm tall

US

ave

: 74 (f) – 86.4 (m) kg

~present-0.3 MYASlide48

Homo sapiens

Appeared ~200,000 years ago with a suite of behaviors similar to

neanderthals

Likely in small populations (~140) with a total number of 100,000

Bottleneck reduced to ~10,000 individualsSlide49

Theories regarding the origin of Homo sapiens

Recent Out of Africa

More consistent with the genetic data

Mitochondrial

Y-chromosome

Genetic variabilityConsistent with language familiesNeanderthals a different species

Multiregional Hypothesis

Explains racial differences by isolation and periodic mixing between populations

Connects

H. erectus

directly to

H. sapiens

Neanderthal a step in the evolution of modern humansSlide50
Slide51

Genetic variation in Homo sapiensSlide52

Classic archaeologically-accessible evidence of behavioral modernity includes:

finely-made tools

fishing

evidence of long-distance exchange or barter among groups

systematic use of pigment (such as ochre) and jewelry for decoration or self-ornamentation

figurative art (cave paintings, 

petroglyphs

, figurine)

game playing and music

foods being cooked and seasoned instead of being consumed in the raw

burial

Calvin. 2003.

A Brief History of Mind;

Stringer. 2011.

Origin of our SpeciesSlide53

Homo sapiens, the generalist

Rick Potts of the Smithsonian InstitutionSlide54

Why are we the last ape standing?

We were lucky

We outcompeted the other bipedal apes

We killed the other bipedal apesSlide55