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BiologyHSC CourseStage 6
The human story
Part 3: The hominin debate
Incorporating October 2002
AMENDMENTS
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Part 3: The hominin debate 1
Contents
Introduction ................................................................................3
The hominins .............................................................................5
The Australopithecines.......................................................................12
The genus Homo................................................................................20
The Leakey family....................................................................37
Louis Leakey ......................................................................................37
Mary Leakey .......................................................................................40
Richard Leakey...................................................................................41
Alternative models of human evolution ....................................43
Different theories ................................................................................45
Summary..................................................................................51
Suggested answers .................................................................53
Exercises – Part 3....................................................................55
Additional resources ................................................................61
The Human story................................................................................62
2 The human story
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Part 3: The hominin debate 3
Introduction
Continuing the human story you will be looking at human evolution and the debate about
human evolution. Humans developed from primates or ape–like ancestors. The first fossil
skull found was in the Neander Valley in Germany in 1856. This strange skull was at first
thought to belong to a man suffering a disease such as rickets. It took a while before
scientists would accept that you could have a creature showing both ape and man like
features. This skull was Homo neanderthalensis and since then there have been many fossils
discovered fuelling the debate on human evolution.
In this part you will have the opportunity to learn to:
• examine at least two alternative views of human evolutionary relationships using the
same fossil evidence including:
– Ardipithecus ramidus (Australopithecus ramidus)
– Australopithecus afarensis
– Paranthropus robustus (Australopithecus robustus)
– Paranthropus boisei (Australopithecus boisei)
– Australopithecus africanus
– Homo habilis
– Homo ergaster
– Homo erectus
– Homo heidelbergensis
– Homo neanderthalensis
– Homo sapiens
4 The human story
• compare these hominid groups, including comparisons of:
– body structure
– cranial capacity
– fossil ages and regional locations
– inferred culture
In this part you will have the opportunity to:
• gather process, present and analyse information to provide an overview of the similarities
and differences of the named hominid species and discuss the role of any two species in
tracing evolutionary relationships
• process secondary information and use available evidence to assess the contribution of
one of the following to our increased understanding of hominid evolution:
– the Leakey family
– Johanson
– Broom
– Tobias
– Dart
– Goodall
• gather and process information from secondary sources to analyse and evaluate the
evidence for the alternative models of human evolution
Extract from Biology Stage 6 Syllabus © Board of Studies NSW, originally issued 1999 modified
November 2002. The most up–to–date version can be found on the Board's website at
http://www.boardofstudies.nsw.edu.au/syllabus_hsc/syllabus2000_lista.html
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Part 3: The hominin debate 5
The first hominins can be defined as an animal that walked upright and had characteristics
that were more human than ape–like. There is only one living hominin– Homo sapiens but
this was not always the case. There is evidence to believe that early hominins lived at the
same time and in some cases in the same area.
The hominin story begins four million years ago. There were four major evolutionary phases
during the development of the hominins.
• Australopithecus stage and the occurrence of bipedalism (four million years ago).
• Evolution of the genus Homo with a large brain and the ability to make durable tools (2.5
million years ago).
• Migration of Homo erectus out of Africa (two million years ago).
• Homo sapiens stage (50 000 years ago).
Before looking at the hominins in more detail, it is important to know some of the features of
hominins. An important part of the definition of a hominin is bipedalism.
Recall from an earlier part of this module the meaning of the term
bipedalism.
_________________________________________________________
Check your answer.
The anatomical structures that support bipedalism are:
• position of the foramen magnum centrally located under the skull
• S–shape spine rather than the C–shape of apes
6 The human story
• non–opposable toe
• straight finger bones
• the femur sloping inwards.
If a fossil has these features then this is evidence for an advanced hominin.
As well as the features that support bipedalism (walking on two feet), there are some other
features that anthropologists look for. These are the increase in brain capacity (apes are less
than 400 cc), a parabolic jaw rather than the rectangular jaw of apes, no eyebrow ridges and
the presence of a chin.
The foreman magnum in humans is located centrally under the skull.
Femur sloping inwards is an indication of bipedalism.
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Part 3: The hominin debate 7
The human spine is S–shaped rather than C–shaped ape spine.
Increased brain capacity from 400 cc in apes to 1500 cc in humans.
Human feet have an arch and a non–opposable big toe.
8 The human story
The human jaw is parabolic compared to the rectangular shape of the ape jaw.
Complete the table below to show the features that anthropologists look for
in fossil hominins.
Anatomical feature Ape – like (primitive) Human – like (advanced)
foramen magnum
shape of spine
big toe
shape of finger bones
slope of the femur
eyebrow ridges
chin
jaw shape (dentalarcade)
brain capacity
Check your answers.
You are going to read about the following species that illustrate the
development of the hominins. Below is a table to summarise the
information that is given. Fill in the table as you read through the
information. The first one is done for you.
• Ardipithecus ramidus
• Australopithecus afarensis
• Australopithecus africanus
• Paranthropus robustus
• Paranthropus boisei
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Part 3: The hominin debate 9
• Homo habilis
• Homo ergaster
• Homo erectus
• Homo heidelbergensis
• Homo neanderthalensis
• Homo sapiens
minin Bodystructure
Cranialcapacity (cc)
Fossil age andlocations
Inferred culture
pithecus ramidus ape–like body unknown butless than 420cc
Eastern Africaand Ethiopia4.4 millionyears ago
unknown
tralopithecus afarensis
tralopithecus africanus
anthropus robustus
anthropus boisei
0 The human story
mo habilis
mo ergaster
mo erectus
mo heidelbergensis
mo neanderthalensis
mo sapiens
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Part 3: The hominin debate 11
The map below shows the location of important hominin sites throughout Africa. As you read
through the information, locate the sites mentioned on the map.
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The Australopithecines
A general description of an Australopithecus is an animal 1.2 to 1.5 m tall, which stood
upright and walked bipedally with a cranial capacity of 450 to 650 cc. The cranial capacity is
the internal capacity of the skull case.
To get an idea of the size of this hominin’s brain fill a container with
400 mL of water. This is similar in size to an Australopithecus brain.
Now fill a container with 1550 mL this is approximately the size of
your brain.
The foot of Australopithecus had a human appearance but the fingers were not as nimble as
ours. The spine was S–shaped and the foramen magnum pointed down both evidence for a
bipedal gait. Australopithecus was an ape–like human.
Australopithecines are split into the gracile form and the robust form. The gracile form was
smaller and had thinner bones while the robust form had thicker bones and much larger teeth.
There were different species of Australopithecus living at the same time. There was a
light–bodied meat eating species called Australopithecus africanus living at the same time as
Australopithecus afarensis and a heavier herbivorous species called Australopithecus
aethiopicus.
Two other species called Australopithecus boisei and Australopithecus robustus lived more
2 The human story
recently and at the same time as the first Homo species. The robust australopithecines are
sometimes put into the separate genus Paranthropus.
As you read about these groups you will see different naming systems in nearly every
resource that you read. This is an indication of the arbitrary nature of classification systems.
If you look at the table below you will see two classification systems for Australopithecus.
One genus–Australopithecus
Two genera– Australopithecusand Paranthropus
A. afarensis A. afarensisgracile
A. africanus A. africanus
A. robustus P. robustusrobust
A. boisei P. boisei
Australopithecus may or may not have been ancestral to modern humans but they were
around for at least three million years so they were a very successful group of animals.
Ardipithecus ramidus
Ardipithecus ramidus (also known as Australopithecus ramidus) lived in woodlands in eastern
Africa, and the Awash Valley in Ethiopia 4.4 mya (million years ago). It is characterised by
having thinner tooth enamel and to show more primitive features relative to other
Australopithecines. The brain size is unknown. It is thought to be close to the divergence of
the African apes from the hominins.
Don’t forget to fill in the table as you read through the information.
Body structure
A small body, more ape–like than hominin. Possibly bipedal or semi–bipedal approximately
122 cm tall. The teeth are intermediate between extinct apes and Australopithecus afarensis.
Cranial capacity
The cranial capacity is unknown because not enough pieces of the skull have been found. It is
assumed to be smaller than Australopithecus afarensis.
Fossil age and locations
Eastern Africa and the Awash Valley, Aramis in Ethiopia 4.5 to 4.4 mya (millions of years
ago).
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Part 3: The hominin debate 13
Inferred culture
The culture of the animal is unknown but it has not been found in conjunction with tools. It is
suggested that this hominin lived in a woodland environment but was bipedal which goes
against the general idea that bipedalism evolved in an open savannah. Some classification
systems do not put this species in Australopithecus.
Australopithecus afarensis
Australopithecus afarensis (the southern ape of Afar) is humanlike in that it has small canines
and thick enamel on the teeth. The shape of the teeth row shows neither the U–shaped
(rectangular) arch of apes nor the parabolic arch of humans. The overall head shape is like an
ape with a small brain but with strong adaptations for bipedal walking although with slightly
curved feet and hands which suggests that they climbed in trees as well.
Fossil jaw from Australopithecus afarensis. The jaw is more rectangular than parabolic.(Photograph: © Dr. Mark Leney hominid.webjump.)
This was named after the Afar region in Ethiopia where the first fossil was found three to four
million years ago.
These creatures were intermediate between apes and modern humans; they had a small brain
but an upright posture and bipedal gait. They did not use fire or tools. Key sites for this
species include Laetoli in Tanzania and Hadar in Ethiopia and two sites in South Africa,
Sterkfontein and Makapansgat. Australopithecus is not found outside of Africa.
4 The human story
Body structure
This hominin was bipedal with an upright posture. The spine was
S–shaped and the foramen magnum pointed downwards. The teeth are small and
unspecialised. They were 1.0 m to 1.5 m tall and weighed 28 kg (30 to 40 kg). They were
sexually dimorphic with the males larger than the females. The build was light with some
ape–like features, for example the shape of the thorax, long arms relative to legs and curved
finger bones. This suggests that they spent some time in the trees.
They also had a low flat forehead, projecting face and prominent eyebrow ridges.
Cranial capacity
Cranial capacity was between 420–490 cc.
Fossil age and locations
The fossil age is three to four million years. It was found in eastern Africa.
The most famous example of this species is ‘Lucy’ who was discovered by Donald Johanson
and Tom Gray in 1974. Lucy is thought to be 3.2 million years old. She was unusual because
nearly half of the skeleton was preserved. She was called Lucy because the Beatles song
‘Lucy in the sky with diamonds’ was popular at the time. Since the discovery of Lucy at least
thirteen individuals of this species had been found in the area and are collectively known as
the ‘first family’.
Another important fossil are the Laetoli footprints discovered by Paul Abell and Mary Leakey
in 1978. This amazing fossil shows that at least two bipedal hominins walked through this
area more than three million years ago. These footprints were preserved because of a
volcanic eruption which left a fine layer of ash. The ash layer was then rained on making a
type of cement.
The footprints were set in the mixture and then covered by another layer of ash and further
layers of volcanic material. The footprints lay beneath the surface for millions of years until
they were exposed by weathering and erosion. Remarkably they were discovered by Mary
Leakey’s team before they weathered away completely.
Inferred culture
Not known to have used tools. Lived in small foraging social groups.
Australopithecus africanus
Raymond Dart, an anatomist named the first Australopithecus, in 1924. It was found in South
Africa leading to the name Australopithecus that means ‘southern ape’. This specimen was
the skull of a child and is called ‘The Taung baby’. It belongs to the species Australopithecus
africanus (southern ape of Africa).
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Part 3: The hominin debate 15
The Taung baby Australopithecus africanus.(Photograph: © Mark Leney hominid webjump)
Robert Broom discovered adults of the same species in the 1930s and since then many
specimens have been found extending north into east Africa. Australopithecus has an
ape–like appearance.
Body structure
Small light build with relatively long arms and more human features such as a high forehead
and less prominent eyebrow ridges. Reduced sexual dimorphism.
Cranial capacity
420–490 cc
Fossil ages and regional locations
Southern Africa extending into East Africa about 2–3 mya.
Inferred culture
Lived in groups.
Paranthropus robustus
Paranthropus robustus (also known as Australopithecus robustus) had a larger brain size
with a heavy body and obvious crest on the head for the attachment of large jaw muscles. It is
not a direct ancestor for modern humans. It was a heavy bodied and heavy jawed herbivore.
This hominin is more massively built than Australopithecus afarensis or Australopithecus
africanus, with a flatter face.
6 The human story
Skull of Australopithecus robustus.
Body structure
The body had a height of 1.75 m and weighed 60 kg. The bony crest on skull, called the
sagittal crest, was the attachment point for the large chewing muscles.
The face was long, flat and broad. The body was robust. They had very thick jaws, small
incisors and canines and very large molars.
The pre–molars were like molars giving a large chewing surface for the vegetarian diet.
Cranial capacity
The cranial capacity was between 450–550 cc.
Fossil age and locations
Found in southern Africa (Kromdraai) and Swartkrans around
3–1 million years ago.
One skull of this species was found with puncture marks in the skull that fit the teeth of a
leopard. It was thought that this fossil was a leopard’s meal but fell into a sinkhole below the
leopard’s feeding tree and became fossilised in the cave deposits.
Inferred culture
Lived in groups. This species arose as the climate became drier and the environment changed
into more open woodland.
Paranthropus boisei
Paranthropus boisei is also known as Australopithecus boisei. This is a hyper–robust form
from East Africa originally called Zinjanthropus boisei by Louis Leakey (nicknamed ‘Zinj’ or
‘Nutcracker man’).
Lived at the same time as Homo habilis in Olduvai Gorge.
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Part 3: The hominin debate 17
Paranthropus boisei showing the sagittal crest and large molars.
Body structure
Thought to be a robust Australopithecus. A shortened but heavily buttressed face, tiny front
teeth and large cheek teeth and enormously developed chewing muscles attached to a sagittal
crest.
Walked upright with a foramen magnum further forward than Australopithecus. Short legs
and long arms.
Cranial capacity
The cranial capacity was between 500–545 cc.
Fossil age and locations
The fossil age is between 1.75 to 1.4 million years ago. Many fossils at Kooba Fora (Kenya).
Olduvai Gorge (Tanzania) and eastern Ethiopia. Similar to Australopithecus robustus but
found in eastern Africa.
Inferred culture
A large robust vegetarian. Possible stone tool user. This species was at first thought by the
Leakey family to be the tool user who belonged to the tools found in Olduvai Gorge but these
were later attributed to Homo habilis who lived at the same time.
The Australopithecines were more ape–like than human and so are not placed in the same
genus as humans.
Do Exercise 3.1 now.
The genus Homo
Australopithecus were found in Africa at the same time as the first of the true humans, Homo
habilis. The Homo genus contains large–brained bipedal animals that use tools.
8 The human story
This next stage of hominin evolution moves out of Africa. The first member of the genus
Homo was discovered in Java by Eugene Dubois in 1890. It had characteristics between
Australopithecus and modern humans and was called ‘Java–man’.
The next discovery was in China and was given the name ‘Peking man’. These have both
been put into the same species, Homo erectus
(‘upright man’). Homo erectus was found throughout Europe 800 000 years ago. In Spain, a
particularly large group of Homo erectus has been named Homo heidelbergensis. Homo
erectus then evolved into archaic Homo sapiens and may be the ancestors of Homo
neanderthalensis. Homo erectus has been found in many locations including southern and
central Europe and east Africa.
The species of the genus Homo that you will be studying are:
• Homo habilis
• Homo ergaster
• Homo erectus
• Homo heidelbergensis
• Homo neanderthalensis
• Homo sapiens.
Homo habilis
By two million years ago the genus Homo was around in the form of Homo habilis. This was
the first toolmaker.
The skull of Homo habilis.
Homo habilis was discovered by the Leakeys in Olduvai Gorge during the 1960s and 70s.
Homo habilis means “handy man”. This name was given because of their simple pebble tools
found with the hominin fossils. This is the first true human.
Body structure
The body had a height 1.3 m and weighed 40 kg with a larger brain size than
Australopithecus. The males are larger than females. They had a rounder head with smaller
molars and less projecting jaws. They had large molars, no chin and a sloping forehead.
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Part 3: The hominin debate 19
Cranial capacity
The cranial capacity was between 500–800 cc.
Jaw of Homo habilis . Compare the shape of this jaw to the shape of the Australopithecus afarensisjaw.(Photograph: © Dr. Mark Leney hominid.webjump )
Fossil age and locations
Found on the shores of Lake Turkana, East Africa, 2.2 million to
1.6 million years ago. Also found at Koobi Fora in northern Kenya and Olduvai Gorge.
Inferred culture
They made and used simple stone tools called Oldowan technology, built shelters, and
cooperated in groups. They ate a mixed diet of plants and animals.
Use the map of Africa to locate these sites. Olduvai Gorge, Lake Turkana,
Koobi Fora, Swartkrans, Kondraii, Sterkfontein.
Simple pebble chopper, part of the Oldowan technology.
20 The human story
Homo ergaster (Turkana boy)
Known as African Homo erectus or early Homo erectus.
Specimens were originally given the name Homo erectus but the name Homo ergaster is
being used more and more for the African finds.
The first discoveries of this species were made by Louis and Mary Leakey at Olduvai Gorge.
Richard Leakey (their son) and his team discovered many finds on the shores of Lake
Turkana. The most spectacular find was Nariokotome (or Turkana) Boy.
Body structure
Homo ergaster had a projecting brow ridge, a short face and the beginnings of a projecting
nose. The cranium was rounded with essentially modern body structure with moderately
large faced skulls that had brains twice the size of modern apes but still half the size of
modern humans. Turkana boy died as an adolescent but would have reached a height of six
feet with long slender limbs. There was a different in brain case construction from the Asian
Homo erectus.
Cranial capacity
Cranial capacity was between 848–908 cc.
Fossil age and locations
This fossil was is dated at 1.7 million years ago. It was found in northern Kenya (Koobi
Fora), to the east of Lake Turkana, Ethiopia, Eritrea. Homo ergaster was the first hominin to
move out of Africa. This species is known as Homo erectus in China and Indonesia.
Inferred culture
Homo ergaster made stone tools called Acheulian industry. Large flakes were made into hand
axes which were very versatile for cutting, and chopping. These tools were more complex
than the simple pebble tools of Homo habilis.
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Part 3: The hominin debate 21
Home erectus
Homo erectus (Peking man) skull cap. Notice the heavy eyebrow ridge.(Photograph: © Dr. Mark Leney hominid webjump)
The skull of Homo erectus (800 00–400 000 years ago.)
Famous examples of Homo erectus are ‘Java man’ and ‘Peking man have been found that
existed 1.7 million to 400 000 years ago. Eugene Dubois discovered the first of these fossils
in 1890 and called it the ‘missing link’ between apes and man. The fossils from China were
lost during the chaos of the last world war (1939–45) but good casts remain of the skulls.
Homo erectus is the earliest trace of humans outside of Africa.
The earliest are in Africa at 1.7 million years of age.
Homo erectus stood upright and was a large brained hominin. Its cranial capacity overlaps
with some modern humans.
Body structure
Homo erectus had a stocky skeleton; the skull had a sloping forehead and large brow ridge.
The face was not as flat as modern humans but was less protruding than Homo habilis. Long,
low skull vaults with sharp angles at the back and protruding eyebrow ridges.
22 The human story
Cranial capacity
The cranial capacity is 900–1200 cc which is about 70% of modern humans but falls within
the range of modern humans.
Homo erectus (Peking man) frontal view.(Photograph: © Dr. Mark Leney hominid.webjump)
Fossil age and locations
Lived 1.7 million to 400 000 to 250 000 years ago. Lived in East Africa for a million years
and spread out of Africa to Asia.
Inferred culture
Homo erectus had a stone tool technology of scraping, chopping, cutting, piercing and
pounding tools. This type of tool is called Acheulian.
More of a scavenger than a true hunter, Homo erectus lived on fruits, nuts, berries, small
animals and larger animals killed by other predators. They lived in caves and used fire. The
flake tools were manufactured from local rock including chert and flint. It is suspected that
they also used wooden and bamboo tools which have not survived to the present day.
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Part 3: The hominin debate 23
Tools of Homo erectus.
Homo heidelbergensis
Specimens that were previously called archaic Homo sapiens have been placed in this group.
They were large brained hominins that may have developed into Homo neanderthalensis 400
000 years ago.
Skull of Homo heidelbergensis.
24 The human story
Views of Homo heidelbergensis skull.(Photograph: © Javier Trueba/Madrid Scientific Films)
Body structure
Sometimes called a large Homo erectus with a bigger brain capacity.
Cranial capacity
The cranial capacity is between 1100 and 1300 cc.
Fossil age and locations
Homo heidelbergensis lived in Europe and western Asia 500 000 to
120 000 years ago. They were in Africa 600 000 years ago.
Inferred culture
Homo heidelbergensis was a stone tool user. They may have invented the prepared core stone
tools.
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Part 3: The hominin debate 25
Homo neanderthalensis
Homo neanderthalensis.(Photograph: © Dr. Mark Leney hominid.webjump)
Neanderthals lived at the same time as early Homo sapiens
(Cro Magnon).
Skull of Homo neanderthalensis (Neanderthal man) 35 000 years ago.
Body structure
Neanderthals were 1.6 m tall. They had a smaller forehead, with a large eyebrow ridge and
more prominent jaw, little or no chin, and a large nose. There was a distinctive swelling at
the rear of the skull with a big area for the attachment of the neck muscles.
Their bodies were strong and muscular. Neanderthals were stronger and more robust than
modern humans but generally shorter with a broad rib cage. The forearms and lower legs
were relatively short and the lower limb bones were heavily built with broad fingertips. They
lived through the European ice ages and were adapted to cold conditions.
26 The human story
Cranial capacity
They had a rounded cranium, sloping forehead, thick brow–ridges and an underdeveloped
chin. Cranial capacity 1500 cc (1400–1750 cc). On average, larger than the modern
population.
Fossil age and locations
Lived in Europe and western Asia during the ice age, 230 000 to 30 000 years ago.
Inferred culture
Their culture was called Mousterian and their tools consisted of scrapers, stone knives, and
projectile points for spears and arrows. Tools crafted from bone were also used. They were
wandering hunter/gatherers.
They dug traps and had a high degree of social organisation. They had burial rituals and built
shelters from animal skins, wore clothes and jewellery. They had a complex social
organisation that allowed them to hunt large animals such as woolly mammoth, bears and
bison.
They lived in the cold conditions of the last ice age. Lived in caves and used fire. Specimens
have been found that were partially blind, one armed and crippled. This indicates that there
was a complex social system that looked after the weaker members of the group.
Tools of Homo neanderthalensis (Mousterian technology).
The group died out 30 000 years ago. There is some controversy about whether Cro Magnon
killed or interbred with the neanderthals.
Some recent fossils show intermediate characteristics between the two while the results from
DNA examination shows no interbreeding between the species.
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Part 3: The hominin debate 27
Homo sapiens
Cro Magnon skull.(Photograph: © Dr. Mark Leney hominid.webjump)
The earliest types of this modern species are called archaic Homo sapiens. Archaic Homo
sapiens is a classification that contains fossils that do not fit easily into existing groups.
These hominins were not quite Homo sapiens but they possessed many modern features.
Cro Magnon is the same species as present day humans and is structurally identical to
humans. Their hunting skills surpassed the Neanderthals. They killed dangerous species like
woolly mammoths, sabre toothed tigers and giant ox. They may have contributed to the
extinction of these species. Cro Magnon left behind artworks on the walls of caves.
Skull of Cro Magnon.
Body structure
Well–developed chin, no eyebrow ridges, high forehead, skull long and narrow but the face
was wide. Structural identical with modern humans.
28 The human story
Cro Magnon skull showing the position of the foramen magnum and the parabolic shaped dental arch.(Photograph: © Dr.Mark Leney hominid.webjump)
Cranial capacity
Cranial capacity was between 1350 – 1500 cc.
Fossil age and locations
130 000 years ago in Omo in East Africa. Cro Magnon man moved into Europe. Fossils
found all over the world.
Inferred culture
Cro Magnon had a sophisticated culture with complicated tools.
They constructed lean–tos and huts with stone foundations.
They buried their dead with ritual, made cave paintings, and made bone and ivory tools.
Their art is found in the famous caves of Lascaux in France and Altimira in Spain.
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Part 3: The hominin debate 29
Cro Magnon cave art.
Further development included the domestication of animals, agriculture, wooden weapons,
city dwelling, and eventually leading up to today's technology.
Cro Magnon blade tools.
Make sure you have finished filling in the table and check your answers.
Summary of hominin evolution
There are a number of trends from early Australopithecus to present day humans. These are
• increasing brain size
• increasing body size
30 The human story
• increasing use and sophistication of tools
• decrease in tooth size
• decrease in skeletal robustness.
There is much debate on the shape of the hominid family tree.
The robust australopithecines are not ancestral to humans but are on a separate branch. It is
possible that Homo habilis is a descendant of Australopithecus afarensis but it is still a matter
for debate. It is thought that Homo habilis became Home erectus but there is still debate
about the evolution of and relationship between Homo sapiens, Neanderthal and other archaic
sapiens. You will be looking at the different classification schemes later in this part.
Use the following table to graph the cranial capacity for each of the
hominins listed.
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Part 3: The hominin debate 31
Hominin Cranial capacity range (cc)
Ardipithecus ramidus Unknown but less than 420
Australopithecus afarensis 420–490
Australopithecus africanus 420–490
Paranthropus robustus 450–550
Paranthropus boisei 500–545
Homo habilis 500–800
Homo ergaster 848–908
Homo erectus 900–1200
Homo heidelbergensis 1100–1300
Homo neanderthalensis 1400–1750
Homo sapiens 1350–1500
Graph the time span of each of the hominids using a different colour for
each.
Hominid Time span (years)
32 The human story
Ardipithecus ramidus 4.4 million
Australopithecus afarensis 4 to 3 million
Australopithecus africanus 3 to 2 million
Paranthropus robustus 3 to 1 million
Paranthropus boisei 1.75 to 1.4 million
Homo habilis 2 to 1.6 million
Homo ergaster 1.7 million
Homo erectus 1.7 million to 250 000
Homo heidelbergensis 700 000 to 400 000
Homo neanderthalensis 200 000 to 35 000
Homo sapiens 130 000 to present day
You need to learn the names of all the hominins that have just been mentioned. Take some
time now to learn the names and the similarities and differences between the different fossils.
Do Exercise 3.2 now.
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Part 3: The hominin debate 33
The Leakey family
In the last section the names of Louis, Mary and Richard Leakey occurred as the first to find
species of hominins. The Leakey family has been foremost amongst anthropologists. No
other family has so dominated a field of research as the Leakey family. Their combined
research has added much to the knowledge of hominin evolution.
The three most famous members of this family are:
• Louis Leakey
• Mary Leakey
• Richard Leakey.
Louis Leakey (1903–1972)
Louis Leakey was described as ‘brilliant, passionate, energetic, eccentric and occasionally
erratic’.
He was born outside of Nairobi in 1903. His parents were English missionaries to the Kikuyu
tribe. Louis grew up playing with the tribe; he spoke the language fluently and was initiated
into the tribe. At the age of 13 he found some stone tools and he was determined to study in
this area.
When he attended University in England a rugby accident gave him epilepsy and headaches
and stopped his studies but he still managed an expedition to Africa. He returned to his
studies in 1925 with brilliant passes in anthropology and archaeology. He married Frida
Avern in 1928. His studies led him to believe that man developed in Africa rather than Asia
as was popularly thought at the time.
In 1930 he was awarded a PhD. In 1933 he started an affair with Mary Nicol despite the fact
that he had a pregnant wife and one child.
This scandal plus his work with the geologist Percy Boswell, who ridiculed his aging of his
Olduvai finds, destroyed his chance of an academic career.
In 1936 he married Mary Nicol. During World War II Louis worked in intelligence as a spy.
After the war he took a poorly paid job as curator of the Coryndon Museum (now Kenya
National Museum). In 1947 he organised the first Pan–African Congress of Pre–history and
restored his reputation as an important scientist.
He and his wife Mary excavated Olduvai Gorge in Tanganyika (now Tanzania). In 1959
Mary discovered a hominin skull that they called Zinjanthropus boisei. This outstanding find
brought them celebrity and grants came pouring in. The National Geographic Magazine took
34 The human story
an interest in their work and from that time on wrote many articles about their discoveries and
provided funds for them to continue their work. With this funding they were able to widen
their excavations and found many more hominin fossils including the toolmaker that they had
been looking for, Homo habilis.
While Mary stayed behind continuing the excavations Louis spent more time travelling the
world and raising funds for the digs. He was also interested in other projects and it was his
influence that started some major projects into primate behaviour. The most famous
examples of these were Jane Goodall’s work on chimpanzees, Dian Fossey’s gorilla work and
Birute Galikas studies of orangutans. He was also involved in the search for ancient
civilisations. He travelled constantly speaking to groups of people and raising money for the
work that Mary was doing in Olduvai Gorge. He developed medical problems and collapsed
and died in England in 1972 aged 69.
A few days before his death his son Richard showed him his latest fossil find which supported
Louis’s theory that the hominins had been around for a long period of time and were not
descended directly from the Australopithecines.
Louis Leakey is remembered for his study of Olduvai Gorge and the hominin fossils within it.
He successfully put forward the idea that East Africa was an important area for the evolution
of the hominins and that the evolution of humans was slower than previously thought.
Most fossil finds are open to different interpretations due to the lack of actual remains. Often
only a few pieces of a fossil are found. The nature of fossilisation is such that it is mainly the
teeth and the skull bones that remain to be found. Therefore a whole species may be based on
just a few pieces of bones. This is true for the first remains of Homo habilis found at Olduvai
Gorge by Louis Leakey.
At the same time that Paranthropus boisei lived in Olduvai Gorge there lived another fossil
hominin. The Leakeys were finding many tools in their diggings and they wanted to find the
toolmaker. At first they thought it was Paranthropus boisei but then they started finding
small pieces of bone that belonged to another species.
When they announced in Nature magazine that they had found the toolmaker and it belonged
in the same genus as modern humans there was a public outcry. Experts disagreed with the
reconstruction of the find and the reasons for placing the fossil in the genus Homo. It was
said that Homo habilis was not significantly different from Australopithecus africanus.
The fossil evidence was originally a few fossil bits and pieces–a lower jaw, parts of a brain
case and some body bones. Added to these parts of another brain case and a pair of upper and
lower jaws. This was described at the time as a ‘jumble of fossils’. Up to this point it was
thought that only one species of hominin lived at any one time and that this species evolved
directly into the next hominin. The evidence from Olduvai Gorge was that there were more
than one species living at the same time. This was the first time it was suggested that there
were two species of hominins living at the same time and the same place. It meant that not
every hominin was on a direct line to modern humans.
Another problem was placing the fossil into an already existing genus with only a few pieces
of bone as evidence. A criterion for inclusion in the genus Homo is a brain size of 700–800
cc. When announcing the discovery the Leakey team suggested that a brain size of more than
600 cc was sufficient for inclusion in the genus Homo. Their first specimen had a brain size
of 680 cc, walked upright and used tools with a precision grip.
Tool use as a criterion for inclusion in Homo also caused debate.
Species are usually defined by anatomical features not by behaviour. Leakey wanted to use
tool–use as a definitive part of the genus, Homo.
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Part 3: The hominin debate 35
Amongst taxonomists there are two main groups called the ‘splitters’ and the ‘lumpers’. As
the name suggests splitters want to put each new find into a new group of its own while
lumpers want to place each new find into an already existing group.
The new species Homo habilis was greeted by these two groups with two different points of
view. The lumpers wanted it placed with either Australopithecus or Homo erectus. The
splitters wanted it placed into a species of its own. Louis Leakey was known as a splitter and
had already named fossils as different species that had been discarded by the scientific
community.
The main difference between Homo habilis and Australopithecus africanus was the tool
making and a slightly bigger brain although the teeth were similar.
He popularised the search for hominins bringing many new scientists into this field of study
with his unique style and enthusiasm. He furthered the research into primate behaviour by
setting up the studies of Jane Goodell, Dian Fossey and Birute Galika. His enthusiasm was
infectious.
He traveled the world raising funds and lecturing while Mary stayed behind and carried out
the research.
Mary Leakey (1913–1996)
Mary was born Mary Nicol in 1913. Her father was a landscape artist and she spent much of
her childhood in Europe. When she was 13 her father died and she was shattered. She moved
back to England where she had trouble settling down. She was expelled from two schools
and was known as a rebellious girl.
She became interested in archaeology and worked as a scientific illustrator. She met Louis
Leakey in 1933 and started an affair with him soon after. On his next expedition to Africa she
arranged to meet him on one of the digs. Louis’s wife divorced him and Mary and Louis
were married in 1936. She returned to Kenya with Louis and worked on many excavations in
the following decades.
Her first fossil find was of an extinct primate Proconsul. In 1959 she found Zinjanthropus
boisei (now Australopithecus boisei). From the mid 1960s she lived at Olduvai Gorge often
by herself. She grew apart from Louis partly because of his womanising and partly because
he was working on so many projects. For twenty–five years she worked at Olduvai Gorge
with Louis only making occasional visits.
In 1974 she excavated near Laetoli and in 1978 her team discovered a footprint track left by
two bipedal hominins. The footprints gave a glimpse into the life of Australopithecus
afarensis 3.2 million years ago.
In 1983 she retired from active fieldwork. She died in 1996. Although she never achieved
any academic degrees her work was recognised as outstanding and she is known as a better
scientist than her husband because of her perseverance and meticulous care. She set new
standards in the study of pre–history with her rigorous approach. She was intensely focussed
and diligent. Her major discoveries were the early ape Proconsul, the skull of
Australopithecus boisei and the Laetoli footprints.
36 The human story
Richard Leakey (1944–)
Richard was the second son of Louis and Mary Leakey. At an early age he decided not to
follow in the footsteps of his parents and he dropped out of high school. He started a safari
business and learnt how to fly.
In 1964 he led an expedition to an area that he had observed from the air. He realised that
fossil hunting was in his blood.
In 1966 he married another fossil hunter, Margaret Cropper who had worked with the Leakey
family.
In 1968 he was appointed director of the National Museum of Kenya.
He started looking for fossils in the Lake Rudolf area (now Lake Turkana). The expedition
was a success and many fossils were found including Homo habilis and Homo erectus.
In 1969 his wife had a daughter and later that year they divorced.
The following year he married Maeve Epps, a zoologist.
In 1969 he was diagnosed with terminal kidney disease. His younger brother Philip donated
one of his kidneys to save his brother.
Richard nearly died at this stage but recovered after eight months of near death illness.
In 1984 Richard’s team discovered the most impressive fossil, Turkana boy, this fossil is
nearly a complete skeleton of Home ergaster.
The following year another major find was made the first skull of a new species
Australopithecus aethiopicus. From 1989 to 1994 Richard took up the fight against elephant
and rhino poachers. In 1997 he was elected in the Kenyan parliament.
In 1993 he had a crash in his plane. At the time he was campaigning against poachers and
there is some suspicion that the malfunction of his plane was an attempt to silence him. He
was badly injured in the accident and had both legs amputated below the knees.
His wife, Maeve, continues the family tradition. In 1995 she described a new species
Australopithecus anamensis and in 2001 she announced another species Kenyathropus
platyops. The tradition of the Leakey name lives on.
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Part 3: The hominin debate 37
The table below outlines the events of the Leakey family history.
Year Event
1933 Louis and Mary meet.
1944 Richard is born in Kenya
1959 Mary finds Zinjanthropus (Australopithecus boisei)
1964 Louis finds Homo habilis the tool–maker
1972 Richard finds 1.8 million year old skull and Louis dies a few dayslater
1978 Mary reveals Laetoli footprints (Australopithecus afarensis)
1984 Turkana boy (Homo ergaster) is found, Mary retires
1985 Black skull at Lake Turkana (Australopithecus aethiopicus)
1989 Richard enters wildlife conservation
1993 Richard loses both legs in a plane crash
1995 Maeve Leakey announces new species Australopithecusanamensis
1996 Mary dies at 83
2001 Maeve Leakey announces new species Kenyathropus platyops
There are many sites that deal with the Leakey family. Access them through
http://www.lmpc.edu.au/science
Use your local library, CD ROMs or the Internet to assess the contribution
of the Leakey family to our increased knowledge of hominin evolution.
Do Exercise 3.3 now
38 The human story
Alternative models ofhuman evolution
As each new fossil hominin is discovered, the debate on the evolution of humans is rekindled.
Depending on which classification system you use and whether you are a lumper or a splitter,
there are between eight and eighteen species amongst the fossil hominins. The evidence is
open to different interpretations. As new evidence is found researchers can refine or change
their ideas on human evolution.
Below is a table of alternative names that show the same fossil with different names.
Australopithecus ramidus Ardipithecus ramidus
Australopithecus robustus Paranthropus robustus
Australopithecus boisei Zinzanthropus boisei
Paranthropus boisei
Paranthropus aethiopicus
Homo habilis Homo rudolfensis
Homo erectus Homo ergaster
Archaic Homo sapiens Homo heidelbergensis
Homo sapiens neanderthalensis Homo neanderthalensis
Homo sapiens sapiens Homo sapiens
Table of alternative names.
Some anthropologists believe that all of the hominins may have been on a direct line or there
may have been branches that led to extinction. Others think that there were two or three
parallel lines of evolution with only one leading directly to modern humans. Some of the
scientists want them to group together the fossil hominins others want each new find to be a
separate species.
Below is a collection of family trees for hominins. These are arranged chronologically and
show the changes that have occurred as each new fossil was discovered.
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Part 3: The hominin debate 39
Homo sapiensHomo sapiens Homo sapiens Homo sapiens Homo sapiens
Homoneanderthal
Homoneanderthal
Homoneanderthal
Homo habilis Homo erectusHomo erectus Homo erectus
Homo erectus
Homo habilisHomo habilis
Homohabilis
Homo erectus
Australopithecus
Ramapithecus Ramapithecus
Australopithecus Australopithecus
Australopithecus
Ramapithecus
Ramapithecus
Australopithecus
Le Gros Clark Napier Brace Louis Leakey Richard Leakey
recent
50 000 yrsupperPleistocene150 000 yrs250 000 yrsmiddlePleistocene650 000 yrs750 000 yrslowerPleistocene1.8 million yrs2 million yrsPliocene
5 million yrs
Miocene22 million yrs
?1420
10 00 yrs
Different family trees devised for hominins.
Often the fossils found in different layers in the same area will have a variety of form, sizes
and shapes. There is sexual dimorphism between the sexes of the same species. This leads to
different interpretations.
There is some general agreement about the evolutionary progression from a species of
Australopithecus to Homo habilis to Homo erectus.
In this progression brains become larger, faces shortened, the teeth become smaller and
bipedal walking increased.
Below are three views about the relationship of Australopithecus and its evolution into the
genus Homo.
0.5
Mill
ions
of y
ears
ago
1.5
2.5
3.5
4.5(a)
A. a
fare
nsis
A. a
fric
anus
Hom
o
P. b
oise
i
P. r
obus
tus
Hom
o
(b)
A. a
fare
nsis
A. a
fric
anus
P. b
oise
i
P. r
obus
tus
Hom
o
(c)
A. a
fare
nsis
A. a
fric
anus
P. b
oise
i
P. r
obus
tus
?
?
a) Australopithecus afarensis is the common ancestor of two lineages, one that leads to the Homohabilis branch and the other to the rest of Australopithecus and Paranthropus.
b) Australopithecus afarensis was the ancestor of Australopithecus africanus which then gave rise tothe Homo line and the rest of the Australopithecines
40 The human story
c) A common ancestor gave rise to Australopithecus afarensis and Australopithecus africanus. TheAustralopithecus afarensis line evolved into the genus Paranthropus while an intermediate ancestorAustralopithecus afarensis and Australopithecus africanus became the genus Homo.
Different theories
On a broader view there are several different theories on the shape of the hominin tree.
Below are three diagrams of well–known anthropologists’ view of the hominin family tree.
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Part 3: The hominin debate 41
Johanson’s theory
Australopithecus afarensis is the ancestor of Australopithecines and the genus Homo. The
other Australopithecus and Paranthropus fossils do not lead directly to modern man.
42 The human story
Leakey's theory
Richard Leakey's theory is that the Australopithecines and Homo have a different ancestor. In
Leakey's view the missing link is still to be found and is further back in time.
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Part 3: The hominin debate 43
Tattersall’s theory
The emergence of Homo sapiens has not been a single transformation of one species into
another but a meandering path with extinctions that led nowhere. The robust
australopithecines were a separate branch as was Homo erectus and Homo neanderthalensis.
44 The human story
There is a collection of cut–out cards in the Additional resources.
Each card is one of the species that you have to include in your study of
hominins. Cut these out and them use them to form alternative theories of
hominin evolution such as Johanson, Tattersall and Leakey shown in the
information above.
When you have finished making the trees keep these cards as a handy study item for revision.
Do Exercise 3.5.
You have come to the end of this part of the module. In the next part you will look at the
migrations of hominins from their African origins to their present distribution, worldwide.
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Part 3: The hominin debate 45
46 The human story
Summary
Evolution of hominins
There has been biological evolution in the hominin line over the last five million years from
Australopithecus to modern Homo sapiens.
This change has included:
• Increased size and shape of the skull and cerebral cortex with the size of the brain going
from 400 to 1600 cc.
• Skeletal structures have changed to allow bipedal gait and leaving the hands free to
manipulate tools.
• The larger brain allowed the development of speech and cognitive awareness.
• Changes in the facial shape allowed the development of speech.
• Bipedal locomotion allowed the hands to be free to manipulate tools.
If you were given a skull and asked to determine whether it was more human or ape–like here
are some features to look for.
Human –like features
• small canines, uniform teeth
• shortened jaw–line and face
• no massive eyebrow ridges
• a nasal bridge
• larger brain capacity
• foramen magnum under the skull
• erect head S–shaped spine,
• narrow pelvis
• locking knee joints
Ape–like features
• large canine teeth
• receding chin
• prominent eyebrow ridge
• small brain capacity
• foramen magnum towards the rear of the skull
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Part 3: The hominin debate 47
• C–shaped spine
Leakey family
Louis, Mary and Richard Leakey have been outstanding contributors to the study of hominins.
Their finds include:
Proconsul, Australopithecus boisei, Homo habilis, Homo erectus Australopithecus
aethiopicus. Kenyathropus platyops
Louis Leakey was also instrumental in encouraging the research into primates and in
changing the view that hominins evolved in Asia.
48 The human story
Suggested answers
What is a hominin?
A definition of bipedalism is walking on two feet. Quadrapedalism is walking on four feet.
Anatomical feature Ape–like (primitive) Human –like (advanced)
foramen magnum located towards the rear of theskull
centrally located under the skull
shape of spine C–shaped S–shaped
big toe opposable non–opposable
shape of finger bones curved straight
slope of the femur straight sloping inwards
eyebrow ridges present reduced
chin absent present
jaw shape rectangular parabolic
brain capacity less than 400 cc greater than 400 cc
Hominin Body structure Cranialcapacity(cc)
Fossil age andlocations
Inferred culture
Ardipithecus ramidus ape–like body unknown eastern Africa andEthiopia 4.5 to 4.4million years ago
unknown
Australopithecus afarensis bipedal uprightt
420–490 eastern Africa 4 to3 illi
unknown
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Part 3: The hominin debate 49
posture,S–shapedspine, foramenmagnumpointing down
3 million years ago.
Australopithecus africanus bipedal, upright,slight build
420–490 Southern Africa3–2mya
Lived in groups
Paranthropus robustus height 1.75m.Bony crest onskull, robust
450–550 southern Africa 3 to1 million years ago.
unknown
Paranthropus boisei robust, shortbut heavilybuilt, sagittalcrest, shortlegs, long arms
500–545 east Africa 1.75 to1.4 million yearsago.
possible stonetool user
Homo habilis rounder headand smallermolars
500–800 Africa 2.2 to 1.6million years ago
Oldowan tools,shelters.
Homo ergaster projecting browridge, longlimbs, tall
848–908 Africa 1.7 to 1.4million years ago.
Acheulian tools.fire–users
Home erectus stocky, lessprotruding face
900–1200 Africa, Asia,Europe, 1.7 millionto 250 000 yearsago
Acheulian tooltechnology
Homo heidelbergensis large Homoerectus
1100–1300 Europe, westernAsia125 000–500 000years ago
Acheulian tools
Homo neanderthalensis 1.6 m tall,smallerforehead, largeeyebrow ridge,little or no chin
1400–1750 Europe, westernAsia200 000–30 000years ago
Mousterian tools,burial rituals, builtshelters fromanimal skins
Homo sapiens well developedchin
1350–1500 All over the world130 000 to present
complicated toolsand socialstructure
50 The human story
Exercises – Part 3
Exercises 3.1 to 3.4 Name: _________________________________
Exercise 3.1: Australopithecusa) Name two members of the Australopithecus genus.
_____________________________________________________
b) What is the difference between gracile and robust body structures and give an example of
each type.
_____________________________________________________
_____________________________________________________
_____________________________________________________
c) What are the cranial capacities for?
Ardipithecus ramidus, Australopithecus afarensis and Paranthropus robustus.
_____________________________________________________
_____________________________________________________
_____________________________________________________
d) Some Australopithcines have been placed in the separate genus Paranthropus. Why?
_____________________________________________________
_____________________________________________________
_____________________________________________________
Exercise 3.2: The genus Homoa) Brain capacity is used in the classification of hominin fossils. What is the difference
between the brain capacity of Homo habilis and Homo sapiens?
_____________________________________________________
_____________________________________________________
_____________________________________________________
b) Name five members of the genus Homo and give the cranial capacity of each.
_____________________________________________________
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Part 3: The hominin debate 51
_____________________________________________________
_____________________________________________________
c) Bipedalism is thought to have reduced the surface area for heat to strike the human body
and increase the surface area for cooling breezes. Name another advantage of
bipedalism.
_____________________________________________________
d) What features of a fossil would you look for to indicate that it was bipedal?
_____________________________________________________
_____________________________________________________
_____________________________________________________
e) From your graph how has the cranial capacity of fossil skulls changed?
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
52 The human story
Exercise 3.3: The Leakey familya) The Leakey family is famous for the work they have done on early hominins. What
contribution to the understanding of human evolution is attributed to this family?
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
b) Name three early hominins and name the people who discovered them.
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
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Part 3: The hominin debate 53
Exercise 3.4: Alternative models of human evolutiona) Different anthropologists have different views of the shape of the hominin tree. In the
space below draw two different hominin family trees. State the anthropologist that put
forward the theory and express your opinion on which is the most likely from the
available evidence.
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
54 The human story
b) Below are two different interpretations of hominin family trees. Why is it possible to
draw different conclusions from the same evidence?
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
c) Discuss the role of any two hominins in tracing evolutionary relationships.
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
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Part 3: The hominin debate 55
56 The human story
Additional resources
Australian hominin fossils
People first arrived in Australia by sea 60 000 to 40 000 years ago. The fossil remains that
have been found show great differences and unexpected dating.
The earliest remains were found at Lake Mungo in NSW and are dated at 60 000 years old.
The most famous skeleton of this group belongs to a skeleton known as Mungo man. This is
the skeleton of a tall man. Red ochre is present in the grave suggesting the idea that the site is
a ritual burial. Some researchers sat that the bones of Mungo man are gracile and share
features with fossils from China.
Another type of fossil hominin comes from Kow swamp in Victoria. These fossils are robust
and share features with fossils found in Indonesia. They have large heads with thick bones
with prominent brow ridges and flat foreheads.
It is possible that there was more than one migration into Australia and the present population
is a result of the interbreeding between these two populations.
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Part 3: The hominin debate 57
This article comes from the magazine New Scientist. This is a respectable scientific
magazine. Each article has been peer reviewed and is a good source of secondary material.
The human story
Ann and Patrick Fullick
‘Humans could justifiably be called the most successful of all living organisms. We have
colonised every continent, and our technology, cultures, communication skills and use of
world resources make us appear very different from the rest of the animal world. Yet we
have a remarkable biological similarity to our nearest living relatives, the chimpanzees.
No one knows for certain when our lines diverged the evidence is hard to find and difficult
to interpret, so models of human evolution are constantly disputed and altered. In 1859,
Charles Darwin’s book On the Origin of Species made the idea of ape ancestry a compelling
scientific hypothesis. Since then, many hundreds of fossils and many tens of thousands of
stone tools have been found to prove that Darwin’s theory applies to humans.
The prehistoric evidence as well as comparisons between living humans and other animals,
and the study of human culture–tell us more each day about the path we trod between the
African forest and modern life.
Humans are mammals, just like horses, mice and dolphins. More precisely, we are primates,
a group of mammals that first appeared more than 60 million years ago and which includes
the lemurs, monkeys and apes. Primates are especially good at surviving in the trees.
Climbing and running through branches requires dexterity, good eyesight and excellent
judgment – a fall from a tree can be fatal, and food trees and insects must be discovered,
remembered, gathered and caught. Primates are well endowed with brains. They can
manipulate food items with their hands. They generally give birth to only one offspring at a
time, and consequently have good maternal care, which ensures a good chance that at least a
couple of the low number of offspring survive to reproductive age. The primates are long
lived by comparison with other mammals of similar size. Chimpanzees regularly reach their
forties in captivity, while the much bigger horse is old in it’s twenties.’
58 The human story
Ardipithecus ramidus
Unknown
tructure: some ape–like features
al capacity: unknown
ons: Eastern Africa, Ethiopia.
4.4 to 4.5 mya
e: Lived in groups.
Australopithecus afarensis
Body structure: Gracile, some ape–like features
Cranial capacity: 420–490 cc
Locations: Eastern Africa, Ethiopia.
Age: 3 to 4 mya
Culture: Possibly made and used tools.
Australopithecus africanus
tructure: Small gracile type,
al capacity: 420–490 cc
ons: Southern Africa.
2 to 3 mya
e: Lived in groups.
Paranthropus robustus
Body structure: robust, sagittal crest.
Cranial capacity: 450–550 cc
Locations: Southern Africa
Age: 1 to 4 mya
Culture: Lived in groups
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Part 3: The hominin debate 59
Paranthropus boisei
dy structure: Hyper–robust
anial capacity: 500–545 cc
ations: Eastern Africa
e: 1.75–1.4 mya
ture: Possibly made and used tools.
Homo habilis
Body structure: Gracile
Cranial capacity: 500–800 cc
Locations: Eastern and southern Africa
Age: 2 to 1.6 mya
Culture: Oldowan tool technology.
Homo ergaster
dy structure: Gracile
anial capacity: 848–908 cc
ations: Africa
e: 1.7 to 1.4 mya
ture: Acheulian tools technology.
Homo erectus
Body structure: Stocky with a large brow ridge.
Cranial capacity: 900–1200 cc
Locations: Africa, Europe and Asia
Zhoukoudian Cave, China
Age: 1.7 million to 250,000 years ago
Culture: Acheulian tool technology.
60 The human story
Homo heidelbergensis
dy structure: Large bodied.
anial capacity: 1100–1300 cc
cations: Europe and western Asia
e: 700,000 to 125,000 years ago.
lture: Made and used tools.
Homo neanderthalensis
Body structure: Very strongly built, strong
muscular body
Cranial capacity: 1400–1750 cc
Locations: Europe and western Asia
Age: 100,000 to 35,000 years ago.
Culture: Mousterian tool technology. Buried
dead.
Homo sapiens
dy structure: Modern human structure
anial capacity: 1350–1500 cc
cations: World wide
e: 130,000 to present
lture: Art, burial practices, advanced tool
king
Cut–out cards forming family tree.