Kingdom
Phylum
Class
Order
Family
Genus
Species
Animal
Chordate
Mammal
Primates
Hominids
Homo
Sapiens
Paleoanthropologist
 Scientist who studies
fossil evidence of
human evolution.
Homininds
 Group that includes
humans and their
immediate ancestors.

It is very rare to find a complete skeleton of a
fossilized hominid.

Scientists need to look at many different things to try
and piece together the puzzle of human evolution.

When hominid fossils are found, several important
characteristics can help determine origin and lifestyle
of the species.
 Did organism walk upright?
 Curvature of spine, position where spine
attaches to skull and shape of pelvis
 Brain size?
 Examine skull fragments
 Diet?
 Wear and tear on fossilized teeth
 How and where did it live?
 Fossils found in same area & environment found

2 Divisions of
Primates



1. Anthropoid primates
2. Prosimean primates
Characteristics:



Flat Nails (no claws)
Prehensile hands and
feet (grasping)
Color vision and depth
perception

Include:

marmosets
Monkeys
Apes
Humans

Brain size



 Large relative
to their body
size
Opposable
thumbs
 Similar dental
formula

 number and
arrangement
of teeth






Bipedalism – Ability to walk on 2
feet
Aligned toes = Bipedalism
Enlarged brain =Vertical face
Areas for speech in the brain
S- shaped spine
Bowl-shaped pelvis

Include:



Lemurs
Lorises
Tarsiers



Hominids include humans and extinct
humanlike primates
The oldest known hominid fossils are between
6 and 7 million years old
First fossils found in Africa





Oldest known genus of hominids
Lived more than 4 million years ago
Knee joints- Allow bipedalism!
Australopithecus anamensis
Australopithecus afarensis – believed to have given
rise to:




A. africanus
A. robustus
A. boisei
more than 1 million years ago
NOT ancestral to modern humans!
Australopithecus, 4-3 myrs ago
Chimpanzee
Modern human

!

!


Fossils of nearly half
complete early hominid
Australopithecus afarensis
suggests hominids became
bipedal before their brains
began to dramatically
enlarge



Recent discovery
Not clear whether it was bipedal
4.4 million years old
Hominid phylogenetic tree is
very branchy in appearance
 Representing species died out,
leaving no descendants.




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Ancestors to modern humans
Larger brains than australopithecines
May have had speech
Started to develop tools
Homo habilis
Homo erectus
Homo Erectus
Neanderthal
Homo Sapiens

For years, the thinking among anthropologists was that
homo sapiens, being superior to Neanderthal man, ran
him off the planet. More recently, that view has been
discarded and the picture become more complicated.
For one thing, Neanderthals may have mixed with the
ancestor of modern man, which means that we could
be carrying Neanderthal genes.

Reconstructed
Neanderthal
skull
characterized
by prominent heavy
brow ridges and week chin




Cro-Magnons coexisted with
Neanderthals in Europe and
the Middle East for as many
as 50,000 years
Cro-Magnons had domed
heads, smooth brows, and
prominent chins
30,000-year-old Cro-Magnon
artifacts include:
Bone flutes
 Ivory sculptures
 Evidence of elaborate burial
ceremonies


Evolved about 800,000 years ago

A) Neanderthals
 Were early Homo sapiens
 They may be ancestral to modern humans OR
 They may have died out and been replaced by modern
humans


1. some anthropologist think H. sapiens
evolved in PARALLEL from populations of H.
erectus all over the world. (interbreeding)
2. some anthropologists propose that H. sapiens
DESCENDED from H. erectus in Africa and
then dispersed across Earth.

*

Two hypotheses have been proposed for the
evolution of Homo sapiens

“African replacement” hypothesis
 Also called Out of Africa, Recent-African-Origin

“Multiregional origin” hypothesis



Members of the genus Homo made repeated
long-distance migrations out of Africa
beginning 1.8 million years ago
H. sapiens emerged from Africa about 150,000
years ago and spread across the Near East,
Europe, and Asia
The dispersing H. sapiens populations replaced
all other hominids



H. erectus emerged from Africa 1.8 million
years ago and spread across the Near East,
Europe, and Asia
Continued migrations and interbreeding
occurred among widespread H. erectus
populations
Regional populations of H. erectus evolved into
H. sapiens