TWENTY-NINE

Emergent Humanity -

Three Phases:

comprising the Miocene, Pliocene,  and  Pleistocene epochs

adapted from: The Last 2 Million Years of Human Evolution, Stringer, C., Royal Society of London, youtube, 2013;

Human Evolution 150 Years After Darwin, Lieberman, D., Leakey Foundation. youtube, 2014;

and Essentials of Physical Anthropology, Jurmain, R., et al, 2016/2017, pp. 199-284.

I) Early phase: Pre - Australopiths

7 mya - 4 mya - Central and East Africa

still relatively ape-like

arboreal/terrestrial

?origin of tool use

at least 8 Australopithecine species

7 - 6 mya: sahel man, "Toumai"........Sahelanthropus Tchadensis

6.2 - 5.6 mya: Tugen Hills man.........Orrorin Tugenensis

5.8 - 5.2 mya: ancient father.............Ardipithecus Kadaba

4.7 - 4.5 mya: "Ardi"............................Ardipithecus Ramidus

II) Australopithecine phase: 4 mya - 2 mya

"Taung Child" 

3.3 - 2.1 mya

Australopithecus Africanus

1925: Raymond Dart

upright walking

head held like humans

small canines

earliest biped

Toros-Menalla site, Chad, Africa

foramen magnum is more forward, and points downwards, not backwards,

as spinal column becomes perpendicular to the ground

still small, ape-like braincase (<400 cc)

canines become smaller,

as molars (cheek teeth) enlarge

III) Human phase: 2.4 mya - 200,000 ya

effect of climate change:

every 100,000 years - 

warm vs cold

aridity vs precipitation

small ice caps vs large ice caps

last 800 k - increasingly severe climate swings

last 12 k - inter-glacial warming phase

"Handyman" & "Toolmaker"

2.4 - 1.6 mya

H. Habilis

earliest genus "Homo"

fossils resemble human skeletons

"Turkana Boy"

1.8 - 0.05 mya

H. Erectus

out of Africa around 1.8 mya

fossils found in Dmanisi

found in Java

- prominent brow ridge, large face, skull long and low, no chin 

2.4 - 1.6 mya:    Homo habilis - "toolmaker: earliest genus "Homo".

                                                        Fossils resemble the human skeleton

1.9 - 1.5 mya:    Home ergaster - becomes H. erectus after leaving Africa; Nariokotome Boy

                            Homo georgicus

1.8 - .05 mya:    Homo erectus -Turkana Boy

                                                       - prominent brow ridge, large face, skull long and low, no chin

                                                       - out of Africa, around 1.8 mya

                                                       arrives in Europe, 1.5 mya

1.2 - 0.5 mya:    Homo antecessor - "Pioneer Man" - possible cannibalism (800K)

0.6 - 0.2 mya:    Homo heidelbergensis - lineage possibly diverged into H. Sapiens and                                                                                      Neanderthal 0.37 mya

                                                                       - 1907 -1908 Heidelberg jaw  found and published by 

                                                                                                    Otto Schoentensack

0.4 - 0.3 mya:    Homo neanderthalis

                            Homo floresiensis

0.2 - 0.0 mya:    Homo sapiens: exits Africa 200 kya

                                                         possible descent from H. heidelbergensis

                                                         enters Middle East 100 kya

                                                         enters Asia 60 kya

                                                         enters Europe 40 kya

                                                         enters the Americas 30 kya

"Nariokotome Boy"

1.9 - 1.5 mya

H. Ergaster

becomes H. erectus after leaving Africa 1.8 mya

9 y/o from Kenya

most complete early human skelton

first to use complex tools and fire 

"Pioneer Man"

1.2 - 0.5 mya

 H. antecessor

 possible cannibalism (800K)

 

 "Broken Hill skull"

1921: Tom Zwiglaar

dated 0.3 - 0.125 mya

Zambia, Africa

in the Kabwe limestone caves

the first, early human fossil ever discovered in Africa

demonstrates the centrality

of Africa

for human evolution

Homo heidelbergensis

0.6 - 0.2 mya

representative of

Middle Pleistocene  

780 kya - 125,000 kya

hominins of

Africa and Europe,

in contrast to those of Asia

abundant fossil find in Northern  Spain

(Sima de los Huesos)

 split into

H. Sapiens and Neanderthal

0.37 mya

0.2 mya - to present

    H. Sapiens

there follows globalization of several species

with continued encephalization

(although Neanderthal has a larger brain)

final cephalic/head anatomical changes:

braincase becomes more spherical and globular

forehead becomes steeper

face is less protruding, and shifts below braincase

enlargement of temporal lobe:

language, creativity, innovation

accompanies development of

temporal lobe

and

vocal apparatus

increased (omnivorous) dietary range means

energy-rich foods

increased behavioral complexity

includes explosion in

art, language, intelligence, cooking, and tool innovation

endurance athletes in heat

good breeders: females can conceive every 3 - 4 years

brain growth from birth requires 6 more years

"Lucy"

3.7 - 3.0 mya

Australopithecus Afarensis

 1974: Donald Johannson

Hadar region, Ethiopia

probable origin of the Laetoli footprints,

embedded in the volcanic ash in Tasmania

A) Early Pleistocene 2.4 - 1.0 mya

B) Middle Pleistocene (pre-modern) 0.75 - 0.125 mya

C) Modern 0.125 mya - present