||Also called recent. In Australia biotas are much the same as
||Aborigines arrived between 50,000 and 120,000
BP, probably about 60,000 BP.
Extinction of many megafauna species. Those represented at
Naracoorte around 35,000 BP - perhaps because of climate change
and human activity. Dingoes introduced about 4,000 BP. Cool dry
climate and low sea levels alternate with warm wet climate and
high sea levels as polar ice caps expand and contracted.
||Australia drifts into lower latitudes, cools and aridity
sets in. Rainforests continue to decline and eucalypts and
grasslands continue to spread. First appearance of a variety of
modern types of animals including specialised grazers. Many
lineages become gigantic - megafauna.
||Early to Mid Miocene characterised by lush forests (e.g., at
Riversleigh). Australia crashed into
islands of south-eastern Asia, and soon
after rodents enter Australia. By Late Miocene rainforests
decline and grasslands begin to spread.
||By the end of this period koala, kangaroos, possums and
other modern families present. Fossil deposits in Tasmania,
South Australia and Queensland contain diverse vertebrates
faunas, most indicative of forest communities.
||Rainforest covers much of southern Australia. Australia's
oldest marsupials, bats, frogs, and snakes. (Murgon). Non-marine
mammals known from Antarctica-where forests still flourish.
||World climates cool. Mammals begin to diversify on all
continents following decline of dinosaurs. First horses,
primates, carnivores and other groups appear. Marsupials
diversify at least in South America.
||In the early part of this period, Australia is covered by
shallow seas. There were many giant aquatic reptiles in the
seas. Flowering plants appear and rapidly spread. Conifers and
cycads decline. At the end of the period dinosaurs and other
groups became extinct. Australia's oldest known mammal is a
platypus-like animal. Australia's oldest birds. At least some
exchange of plants took place between Australia and the lands to
||Australia's climate is warm and wet. Conifers, ferns and
cycads are plentiful. Many large herbivorous and aquatic
reptiles. Ray-finned fishes present. Earliest birds found in
Mammals diversify, but are tiny, not bigger than mice.
||Mammal-like reptiles present on all continents. Australia's
climate gets warmer and drier. Insects, primitive amphibians and
reptiles well represented. Gondwana begins to break up. First
mammals known from many continents, but not Australia. Many
groups went extinct or sharply declined at the end of this
||Glaciers cover parts of Gondwana. Climates changes to
more temperate with swamp forests. Insects, fish and early
amphibians plentiful, but in Australia, no reptiles. Trilobites
go extinct, major
mass extinction at the end of this period.
||Starts with warm conditions, then glaciers over much of
Gondwana rifts from Laurasia and drifts towards the South Pole.
Club mosses die out and are replaced by hardier seed ferns. Many
kinds of fish and amphibians. First reptiles appear in the
||Plants spread from water margins into swampy areas forming
thick vegetation with tree-like
club mosses and ferns. Fish have
diversified, lungfish, sharks and armoured fish in sea and
fresh water. First
amphibians evolve and move onto the land.
||Life invades the land. Land plants evolve from seaweeds.
Jawless fish and sea "scorpions" live in fresh water. First fish
with jaws appear in seas. First coral reefs formed.
||Varieties of marine life become extensive, brachiopods,
first jawless fish
evolve. Australia's being among the earliest.
||No life on land, but seas teaming with life, including
jellyfish, sea anemones, sponges, trilobites, brachiopods and
|Oxygen becomes abundant in atmosphere and life diversifies.
Multicellular organisms develop from single cellular organisms.
Algae, jellyfish, primitive worms and sponges appear.
|Life evolves at least by 3.5 Ga. Some
cyanobacteria produce oxygen that
forms ozone that shields the Earth from UV radiation that allows
life to exist.