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Australopithecines
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Group of species with the following broad
characteristics:
Fully bipedal
Intermediate teeth
Brains slightly larger than apes
Existed 4.5 – 2 mya
Many species co-existed
Genus Homo
Australopithecines
Early hominids
Australopithecines !!
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CLADOGENESIS OF HUMANS
Homo
Graciles
Robusts
Early hominids
Gracile Vs Robust
More prognathic
Smaller molars
Bigger canines/incisors
Dished face
Bigger molars
Smaller canines/incisors
Australopithecines!!!! More!
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Australopithecus afarensis
This is one of the IMPORTANT ones
Found in Hadar, Ethiopia (East Africa), dating back 3.4 to 3.0
million years ago.
n More apelike in the skull (small brain and jutting-out face).
n Considerable evidence of bipedalism.
n Teeth still more primitive than genus Homo.
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Type specimen:
Lucy
— One of the most complete early
hominid skeletons ever found
— Discovered by Don Johanson of
ASU in 1974
— Provide key data:
— Height – 3’8”
— Weight – 60-70 lbs
— Sexual dimorphism
— Age at death : 18-30
— 3.2 mya
Lucy
Human vs. Lucy
Male afarensis vs. Lucy
Sexual dimorphism is a
product of sexual selection
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Don Johanson
AKA FSLHNTR
Richard Leakey
Brother of Maeve
Laetoli Footprints
Laetoli
Southern Ethiopia
3.6 mya
2 individuals walking
bipedally through ash
- short stride length
- no sign of knuckle
prints
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Just moseyin’ along
Australopithecus africanus
Australopithecus africanus
— Australopithecus
africanus is found
exclusively in South Africa.
— Dates: 3.5-2.2 mya
— Face: Less prognathism
than previous versions
— Skull: less bell-shaped
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Hominid Site: Sterkfontein
— Cave site in South Africa
— Contains the remains of
four different A. africanus
individuals
— All were dinner for some
predator
OR TRY THIS
Homo
Graciles
Kenyanthropus
Robusts
Australopithecus
anamensis
AUSTRALOPITHECUS BOISEI
É Australopithecus
boisei is found in
East Africa.
É Sometimes referred
to a Paranthropus
boisei
É Characteristics
Ð
“Hyper” Robust
Huge cheek teeth
Ð
Large sagittal crest
Ð
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Note manly Fu Manchu mustache
Masticatorymuscles
temporalis
masseter
GORILLA SKULL
Sagittal crest
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MOLARIZARION OF THE PREMOLARS
human
afarensis
boisei
ECOLOGY OF THE ROBUST LINEAGE
Ò Paleoecology
É Edaphic
grasslands and associated wetlands
for hard food items
É Adaptation
Ò Robusts
were highly specialized to their
environment and food source
POSSIBLE FOOD FOR ROBUSTUS
Ò Almost
entirely vegetables
Ò Harder/tougher foods
Ò Nuts, hard seeds, fibrous tubers
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OR WAS IT?!!?
Ò New
research (2009) on boisei examined “usewear” of teeth
É Use
wear are patterns of marks and abrasions left
by some hard substances
Ò This
research did not produce the results we
would expect
Ò What does this mean?
É Anatomy
suggests was [boisei] could eat, but not
necessarily what it did eat
EXTINCTION OF ROBUSTS
Ò Robusts
persist for ~ 1.3 million years (2.5 –
1.5 mya)
Ò World-wide climate grows colder during this
time
Ò Grasslands dry out
Ò Change may have occurred too quickly for
robusts to adapt
Ò Completely disappear from the fossil record
Genus Homo
ICE AGE
Australopithecines
Early hominids
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TheIceAge
DidNOTlooklikethis
—
Pleistocene
Epoch
— ICE AGE – series of
warm and cold
periods (8-10 degrees
cooler on average)
◦ Lasts from 2 million
years ago until 10,000
years ago
— Impact
◦ More water locked in
ice than now
◦ Less water = lower sea
levels (up to 400 feet in
some places)
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IceAgepoint#1– itwasn’talwayscold
IceAge#2:Morewaterwaslockedinice.
Sealevelswere200-300feetlower
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Milankovich Cycles
• Changestotherotation
andrevolutionoftheearth
aroundthesun
– Eccentricity
– Tilt
– Precession
• Evenminorchangescan
havemajorimpacts
• Thesearecycles– not
singleevents
HOMO!
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Genus Homo
Australopithecine
s
Early hominids
HOMO LINEAGE
Ò Definitely
incorporated meat into diet
in both south and east Africa
Ò Co-existed with robust species
Ò First appear 2.5-2.0 mya
Ò Associated with stone tools
Ò Existed
HOMO DERIVED CHARACTERISTICS
Ò Larger
cranial capacity ( all > 500 cc)
rounding of cranium
Ò Facial prognathism is further reduced
Ò Increased
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HOMO SPECIES
Ò H.
Ò H.
Ò H.
Ò H.
Ò H.
Ò H.
Ò H.
Ò H.
Ò H.
Ò H.
habilis
rudolfensis
georgicus
ergaster
erectus
antecessor
heidelbergensis
neanderthalensis
floresiensis
sapiens
The Origin of the Genus Homo
—
Homo habilis
oLived in Africa
between at least 2
and 1.44 mya.
¡The first discovered
specimens were
found at Olduvai
Gorge in Tanzania in
East Africa.
Homo habilis
—
Physical
Characteristics
◦ 500 cc brain
◦ Teeth – almost
completely humanlike
◦ Still short like a chimp
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The Handy Man
—
—
—
Cranial capacity – 500 cc
Teeth – almost completely
human-like
Most primitive of all Homo
◦ long arms
◦ Short legs
◦ Short stature overall (4.5 ft
fully grown)
◦ Smaller face than
Australopithecus
Homo habilis
—
Cultural Behavior
◦ Developed the
Oldowan tradition—
the oldest known
stone tool culture.
◦ Tools were made from
flint, obsidian, or
quartz.
Oldowan Chopper
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Marrow consumption
Highly nutritious
— Inaccessible to most
carnivores
— First occurrence of
hominids regularly eating
meat
—
Scavenging or Hunting?
If Homo habilis is hunting animals, then we
would expect: cut marks on bone first
then carnivore marks second
— What we get is the exact opposite
—
Last month! (MW)
SUN
MON
TUES
WED
10
Great Apes
12
Great Apes
17
Human Ancestors
19
Human Ancestors
24
Human Ancestors
26
NO CLASS
1
Neanderthals
3
Modern humans
Final Quiz
8 Final exam
@1:00
Final homework
10
THUR FRI
SAT
Thanksgiving Holiday
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Modern Homo sapiens sapiens
Homo sapiens
neandertalensis
Homo sapiens sapiens
TIME
Archaic Homo sapiens
Homo ergaster / erectus
Homo habilis
Australopithecus
More than one species?
◦ It is hard to accurately determine species
differences for genus Homo
H. habilis
H. rudolfensis
Theproblemis…
Homo speciesOVERLAPintime
Homohabilis
Homo
rudolfensis
Homoheidelbergensis
Homoerectus
3.0
2.0
1.0
0
MYA
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H. rudolfensis
◦ Lived in Africa about
1.9 mya.
◦ Its cranial capacity is
larger than H. habilis
(400-800 cc), but more
similar to australopiths
in certain facial
features.
◦ Evolutionary
relationships between
species of early Homo
are very difficult to pin
down.
1.8 million year old fossil
—
1.8 million years
ago
New discoveries…in the Middle East
Dmanisi Hominids
Several individuals
— Very physically
variable…but they
seem to be part of
the same
populations
— Multiple
overlapping species
of hominids
—
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Homo erectus / ergaster
—
—
—
—
—
1.9 – 0.04 mya
“Upright Man” – so
named b/c they were
some of the first
bipedal hominids
identified
Brain size – 8501100 cc
Low forehead
Brow ridges
Youngest (37,000)
Oldest 1.9 my
Homo ergaster
Homo erectus
Homo Erectus
¡ Has a larger brain than
earlier hominids, and
there was a slight
increase in size over
time.
¡ The overall brain case is
still smaller than
modern humans
¡ Brow ridges also
developed over the eyes,
possibly for support for
chewing forces, or as
facial or eye protection.
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Homo Erectus
— Physical Characteristics
¡ Jaws were still large but
smaller than those of
earlier hominid.
¡ Body proportions are
similar to modern
humans.
¡ Limb proportions reflect
a modern bipedal form,
and suggest endurance
running.
Disadvantages
Advantages
— Metabolically expensive
— Intelligence
— Lose heat more quickly
— Toolmaking and tool use
— Can complicate child birth
— Technological skill
— Problem-solving ability
— Language ability
— Social intelligence
Advantages must outweigh disadvantages
The evolution of larger brains
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Acheulean Tools
Acheulean Tools
Used high quality
stone
— Long distance
exchange or transport
— Hunting, not
scavenging
—
SUN
MON
TUES
5
Neanderthals
WED
THUR
FRI
SAT
7
Modern Humans
Final Quiz
12
Final Exam (13)
Final Project
Due
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5/3/16
800,000 years ago
Homo ergaster
Homo erectus
Archaic Homo sapiens
Development and spread of early H. sapiens (500,000)
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Homo sapiens neandertalensis
Homo erectus
Homo sapiens (archaic)
Homo floresiensis
Homo sapiens sapiens
SPECIATION (200,000 years ago)!
Homo floresiensis
Speciation
Homo neanderthalensis
Homo sapiens
Homo heidelbergensis (?)
Homo erectus
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Archaic Homo sapiens
— Has been found at
sites in Europe, Africa,
and Asia.
— Date from 800,000 to
200,000 years ago, a
period of frequent ice
ages, below average
temperatures, and
spreading glaciers over
large continental areas.
— Cranial capacity –
1100-1200 cc
Atapuerca, Spain
400,000 years
ago
— Cave system in
Spain
— First humans in
Europe
— First evidence of
burial culture?
—
Hominids on Ice!
—
Archaic H. sapiens
in Europe had to
deal with cold
temperatures, ice,
and dramatic
weather changes
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Temperature over the last 400k years
Inter-glacial…its warm!
Now
Glacial…its cold!
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