    
Ecological history
of Australia
AN ECOLOGICAL HISTORY OF AUSTRALIA AND ITS
PEOPLES : Tim Flannery
INTRO
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Australia has some of the most
ancient rainforests on Earth
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22nd Dec 1993 Native
Title: brings to a close a period of history when we possessed a purely
European view of land.
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Today one-quarter of all living
Australians grew up in other lands.
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Nature has not endowed Australia
with a good fossil record
IN THE BEGINNING
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120 million years ago
southern Victoria was very much
cooler with a mean temperature of 10 degrees Celsius. Southern Victoria at
this time had to endure between six weeks of total darkness each year. The
plants were dominated by ancient types such as conifers, ferns, cycads,
mosses and lichens with only a few flowering plants. Scientists have
discovered the world’s oldest flower in the rocks – a diminutive magnolia
like bloom perfectly preserved between two layers of clay. Grevilleas and
waratahs evolved after this time. Most of the dinosaurs of Victoria were
curiously small – the most common chicken to dog sized bird-hopping
dinosaurs that ran on their hindlimbs and ate plants. The very largest
Victorian dinosaur was Allosaurus at about 2 metres high. In addition to
the dinosaurs: pterosaurs (flying reptiles) lungfish, turtles and crocodiles
have also been found. Enormous amphibians known as labryrinthodonts were
found in rocks in Victoria too which was a huge surprise for they had become
extinct elsewhere in the world some 80 million years earlier. Also found
preserved were cockroaches, cicadas, fleas, water beetles and
horseshoe-crabs (now extinct in Australia)
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Between 86 and 82 million years
ago a large sliver of land detached itself from eastern Australia – now
largely submerged beneath the sea it included New Zealand, New Calendonia,
Lord Howe and Norfolk Islands.
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New Caledonia:
James Cook in Sept 1774 was the first
European to see the strange island and name it New Caledonia. He noted the
great similarity of it to Australia. There are 3000 species of plants there
– New Zealand has only 1460 species. New Caledonia has some of the most
wildly beautiful and primitive plant species to be found on Earth. Humans
arrived about 3500 years ago
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Gondwana: Antarctic, New Guinea
and parts of Indonesia : 80 million years ago – one land mass. Gondwana
straddled the South pole. Plants still inhabit the fragment that was once
Gondwana ; proteas, waratahs and Macadamia. It was then that Tasmantis
broke adrift raising Australia’s Great Dividing Range
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Australasia = Australia, New
Zealand, New Caledonia and New Guinea
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Australia in one the world’s
most ancient landmasses with rocks 4,000 million years old found in Western
Australia by a North American palaeontologist. This is magnificent as the
earth itself is only 4 600 years old. Life on this earth has existed for
about five-sixths of the planets history.
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Dinosaurs
ruled the planet until 65 million years ago when the asteroid hit Mexico.
Birds and mammals and many familiar plants were already in existence. At
Cape Paterson an anklebone of an Allosaurus was found. Hamilton in Western
Victoria is the site of Australia’s most important fossil localities. It
gives a glimpse of the Victorian rainforest 4.5 million years ago complete
with tree kangaroos, tiny diprotodons and forest wallabies
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New Guinea was named after
Guinea in Africa – both places are home to a dark skinned, crinkle-haired
people.
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Aborigines arrived in Australia
from South-East Asia at least 40,000 and more probably 60,000 years ago.
They travelled on the most basic of watercraft.
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Maoris arrived in New Zealand
from Polynesia between 1000 and 800 years ago
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At present the North Pole has a
positive terminal, but over the past 76 million years the Earth’s magnetic
field has reversed 71 times. No- one knows why but at present the magnetic
field is weakening each decade
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Australia is moving north at the
rate of approximately 6 cm per year.
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We can imagine the earth as
being like an enormous pot of boiling pea soup. The continents are the thin
scum on the top
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For over 40 million years
Australia has been physically isolated from the rest of the world’s
landmasses and in that time the world has chilled considerably.
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25 million years ago the
Australian plate came into contact with the Asian plate causing buckling and
the result was the formation of New Guinea with peaks reaching 4000 metres
high. Erosion from these peaks has produced wondrous soils. The highland
valley of Papua New Guinea
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support some 1614 people per
square kilometre which is the highest rural density supported anywhere on
Earth.
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10 – 5 million years ago much of
Victoria’s Western district was under the sea – the majestic Grampian
mountain range was an island
Papua New Guinea
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210 species of mammals only 35
less than Australia
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840 bird species – Australia has
750
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300 reptile and 220 frog species
against Australia’s 750 reptiles and 250 frog species.
Mammals of Australia
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Marsupials evolved from a South
American ancestor some 60 million years ago.
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Platypus – 20 million year old
fossil found in Northern Australia
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In Queensland 55 million years
ago in “Joh Country” remains of crocodiles and large soft-bellied turtles
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Today half of the Australian
mammal fauna is composed of rats and bats
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23 native mammal species have
become extinct in Australia since the arrival of the Europeans. Tragically,
many of these extinction’s have occurred in the last 30 to 40 years when
environmental awareness might have helped to save them. These historic
extinction’s of Australian mammals are the worst that the world has
experienced in the last 500 years. Many extinction’s happened as late as the
1960’s following the departure of Aboriginal people from their tribal
lands. They suggest that Aboriginal firestick farming was an important
factor in maintaining suitable conditions for the middle-sized mammal
species. A further factor would be feral cats, foxes, dingoes etc.
Fauna of Australia
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Australia supports at least 25
000 species of plants
Rivers
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Most of the rivers of the east
coast have maintained their positions for tens of millions of years
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Some rivers have cut as little
as a few tens of metres deeper into their beds in over 30 million years.
Why are Australia’s soils so poor?
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Without geological activity
(volcanoes) or glaciers, soil cannot be renewed. As a result Australia has
by far the poorest soil of any continent.
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Eroded volcanoes produce some of
the only fertile soil in Australia. Wherever this occurs it supports
intensive agriculture or prime grazing land. The basalt plain of Victoria’s
Western District is the largest of these area.
Arrival of humans
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Until around a million years
ago, the entire panorama of hominid evolution had been played out on the
wide plains and rift valleys of Africa. It was our immediate ancestor,
‘Homo erectus’, that became the first member of our family to leave the
ancestral African home
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‘Homo sapiens’ began to spread
across the landscape
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All living people spread out of
Africa, possibly some 130 000 years ago.
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50 000 years ago our ancestors
had progressed even further as hunters. South African cave deposits show
the remains of prey such as pigs and buffalo, rhino and elephant.
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By 40 000 years ago people
living in northern Africa were making stone points with tangs to which a
handle was attached. Traps were being made using nets and spears
Aborigines – where did
they come from?
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There are no people presently
resembling Aborigines and New Guineas in South-East Asia. One has to go as
far afield as the Phillippines, peninsular Malaysia and the Andaman Island
to find a few tiny groups of pygmy negrito people who look anything like
Australian Aborigines. Researchers have therefore long assumed that the
ancestors of the Australian Aborigines were displaced from their South-East
Asian home by invading Mongoloid peoples.
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1970 – Lake Mungo in Western New
South Wales – remains of cremated woman found in a sand dune dated around 38
000 years ago
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1974 – uncremated fully
articulated skeleton of a adult man was discovered. Pink ochre powder had
been sprinkled over the upper part of his body – 32 000 years old.
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Western Australia revealed human
presence from 30 000 years ago
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Tasmania show caves in the
south-western part of the island at 35 000 years. 7000 years ago evidence
of bone tools and needles used for sewing skin cloaks. 5000 Aborigines
lived in scattered small groups over the Island. By 1830 only 300
Aborigines survived. By 1847 all but 47 had died. The remainder were send
to Flinders Island. Truganini was the last Aborigine in Tasmania dying in
1876. She brought to an end a disastrous close to a chapter of murder and
cruelty. No European was ever tried for the murder of a Tasmanian Aborigine
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Disease was a more important
factor: measles, flu, smallpox, gonorrhoea, syphilis etc.
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Tasmanian Aborigines in 1802
lived in often bitterly cold climates but they lacked clothing and the
ability to make fire – they did not eat
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fish. They had no hafted
implements such as axes, no boomerangs or spearthrowers, no dingoes and no
stone tools
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5000 years ago the manufacture
of stone axes with fine edges became very popular throughout Australia
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Arnhem Land art galleries show
paintings over 3000 years old holding boomerangs
Seas
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Poor land means poor seas too.
The low productivity of Australia seas means that with a mere 17 million
people, it imports $500 million worth of seafood each year
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Our oceans are mirror images of
our land – they are biological deserts of great fragility.
Ice age
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Reached its peak 25 000 to 15
000 years ago.
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Sea levels fell as much as 160
metres.
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Large landmasses suddenly
appeared in the world’s oceans
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Australia was particularly
dramatically affected for the continent became cold and extremely arid.
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The centre was turned into a
vast dustbowl of swirling sand dunes where vegetation could not survive.
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Trees vanished from most of the
land.
Melting of the ice age
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Suddenly 15 000 years ago the
ice-caps melted rapidly
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By 9 000 years ago the world
resembled the one we know today
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Papua New Guineans would have
been in contact with Aboriginal people until 10000 years ago.
1699
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31st August William
Dampier, Captain of the Roebuck met with a party of 10 Aborigines while
searching for fresh water. One Aborigine was shot
1788
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Before European contact
Australia was home to 300000 – 600000 people who spoke 250 languages
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Trade took place with stone axes
quarried at Mount Isa and later found in the Gulf of Carpentaria and pearl
shell from the Kimberley was traded down in southern Australia
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By 1788 Aboriginals had
developed a large number of sophisticated practices for conserving animal
resources. ‘Story places’ were off limits to hunters and acted as
reservoirs for such mammals as tree kangaroos
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The traditional European view of
Aboriginal cultures has been that life stood still for the Aborigines since
they had arrived in Australia. They arrived in the stone age and were still
in it by the time Cook arrived. No agriculture, widespread nomadism (this
was a response of adaption to the erratic availability of resources), simple
dwellings and limited material possessions. This is a superficial and naïve
view. A lack of agriculture ahs long been cited as evidence of the
‘backwardness’ and ‘laziness’ of Aborigines. Many of the features of
Aboriginal lifestyles that we continue to view a primitive are highly
specialized responses to Australian conditions.
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First fleet of convicts arrived
26th January 1788
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It was indeed the British legal
concept of ‘terra nullius’. It gave the British the right to occupy
‘unused’ land.
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Between 1788 and 1890 the
Aboriginal population of Australia was reduced to 50 000.
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In Victoria there were only 1907
Aboriginal people left by 1863. By 1967 there were 3 people of pure
Australoid descent
Corroborees
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Often involved hundreds of
participants drawn from several tribal groups. They could only take place
in exceptional circumstances for enough food to be present in one place to
feed hundreds of people for weeks
Land degradation
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Already after less than 200
years of use, 70% of the 22 million of arable land is degraded and in need
of soil restoration.
Exports
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Today mining earns Australia
some 29 billion dollars while agriculture earns only 16 billion dollars
1993
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22nd December, Prime
Minister Keating recognised the legality of native title in Australia. With
it ‘terra nulius’ was abolished from the law books and gave recognition that
Aboriginal tribal law has a place in Australian society.
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