The Last Ape Standing

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 Man

Mt-DNA Primate Tree

Our Living Sisters

Pan

Gorilla

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

Living Asian Apes

Gibbon (Hyalobates) Orangutan (Pongo)

Apes in the Primates

Features that distinguish the Hominins from other living apes

• 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.

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 locomotion

Oldest evidence of bipedalism

70 footprints in volcanic ash dated to 3.6 MYA, Laetoli, Tanzania, discovered by a team led by Mary Leakey in 1978

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

Features that distinguish the Hominins from other living apes• Neoteny

– Nakedness– Large Brain Size– Reduced Dentition

The Neotenic Apes

Hair loss and lice

Summarized in Reed et al. 2007. Pair of lice lost or parasites regained: the evolutionary history of anthropoid primate lice. BMC Biology 5:7. doi: 10.1186/1741-7007-5-7

Phylogeny of some living primates and their lice

Also from Reed et al. (2007)

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) ~50-100KYA

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

Large Brain

Potts 2011 Navarette et al. 2011

Reduced dentition

 Image from Anthropological Curiosities.

Features that distinguish the Hominins from other apes

• Vocal Communication– Lower larynx– Fox P2 gene

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

PBS NOVA

Proconsul

Likely a sister to the apes with a mix of ape-monkey characters14-23 MYAAfrica

Dryopithecus

Early ape15-9 MYAAfrica, Eurasia

Ardipithecus

• Africa• Brain ~300-350cc• 120 (f) cm tall• 50 (f) kg• ~6.0 – 4.2 MYA

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, NOAA

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, NOAA

Human PhylogenyThe Smithsonian Institution Museum of Natural History

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

(A) Pan troglodytes, chimpanzee, modern(B) Australopithecus africanus, 2.6 My(C) Australopithecus africanus, 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

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 Museum

Australopithecus africanus

• Africa• Brain 420-500 cc• 110 (f)-140 (m) cm tall• 30 (f) - 41 (m) kg• ~2.4-2.8 MYABritish Museum of Natural History and the Smithsonian Museum

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

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, NOAA

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 MYA

Olduwan stone tools in Ethiopia

• 2.6 -1.8 MYA• Chipped pebbles and

choppers, usually lava• Likely made by H. habilis

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.html

Range of H. erectus

• Evidence for controlled use of fire

• Acheulean tools (1.7-0.1 MYA)

http://anthro.palomar.edu

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 Institution

Homo neanderthalensis

• Eurasia• Brain ~1100-1400 cc• 155 (f) – 164 (m) cm tall• 54 (f) – 64 (m) kg• ~0.03-0.3 MYA

Neanderthal Museum

Range of the Neanderthals

http://www.rhesusnegative.net

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 ceremony

• Possible verbal communication

HEAD

TRUNK

SHOULDER/ARM

HAND

PELVISLEG

FOOT05

10152025303540

Neanderthal vs rodeo trama pat-terns (redrawn Berger & Trinkhaus

1995)

NEANDERTHAL

RODEO

Homo floresiensis

• Asia (Indonesia)• Brain ~380-417 cc• ~106 (f?) cm tall• 30 (f?) kg• ~0.013-0.095 MYA

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-0.2 MYA

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 individuals

Theories regarding the origin of Homo sapiens

Recent Out of Africa– More consistent with

the genetic data• Mitochondrial• Y-chromosome• Genetic variability

– Consistent with language families

– Neanderthals 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 humans

Genetic variation in Homo sapiens

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 Species

Homo sapiens, the generalist

Rick Potts of the Smithsonian Institution

Why are we the last ape standing?

• We were lucky• We outcompeted the other bipedal apes• We killed the other bipedal apes