Presentation: Australian Region (Zoogeography)

1. AUSTRALIAN REGION
SYED MUHAMMAD KHAN
(BS HONS. ZOOLOGY)

2. INTRODUCTION
■ The Australian region (also referred to as the Australasian region) includes:
1. Whole of Australia
2. New Guinea
3. Tasmania
4. A few of the smaller islands of Indonesian Archipelago
5. New Zealand
6. Other Pacific Islands
■ Australian and Neotropical regions are the regions which are present in the Southern
hemisphere, hence they were grouped together as a super-region: Notogaea (which
comprises of the southern half of the world’s zoogeographical realms).

3. SUB REGIONS
■ The Australian region, like every other realm, has four sub-regions:
1. Australian Sub-region: It includes Australia and Tasmania, it is located in the
Southern Pacific Ocean.
2. Austro-Malayan Sub-region: This region includes the Malayan Archipelago islands,
New Guinea, Solomon Islands, etc.
3. Polynesian Sub-region: Polynesia is a group of more than 1,000 islands scattered
over central and southern Pacific Ocean (to the east of mainland Australia).
4. New Zealand Sub-region: It is a group of ancient islands, situated to the south-east
of mainland Australia.

4. THE AUSTRALIAN REGION

5. BOUNDARIES
■ It is the only region that does not have any land connections whatsoever with
the world.
■ It is linked with the Oriental region via the Malayan archipelago (which is a
chain of islands extending between these two regions).
■ It has the following boundaries:
1. Pacific Ocean: Eastern boundary (including Northeast and Southeast).
2. Indian Ocean: Western boundary (including Northwest and Southwest).
3. Wallacea: This transitional zone (which lies in the Malayan Archipelago)
separates the Australian and Oriental regions.

6. CLIMATE
■ The northern section of Australia has a more tropical climate, hot and humid in the
summer, and quite warm and dry in the winter.
■ The southern parts are cooler with mild summers and cool, sometimes rainy winters.
■ The seasons are the opposite of those in the Northern Hemisphere-when it's summer in
the north, it’s winter south of the equator.
■ December and January are the hottest months in Australia, July and August the coldest.
■ Tasmania has a cool temperate climate with four distinct seasons.
■ New Zealand's climate is complex and varies from warm subtropical in the far north to
cool temperate climates in the far south, with severe alpine conditions in the
mountainous areas.
■ The climate of New Guinea is tropical.

7. BIOMES
■ The most dominant biomes of Australia are deserts and arid planes, which
are found in its interior.
■ Forests are present in the northern, eastern and southern regions.
■ Grasslands are also present.
■ Most of New Zealand’s biomes are temperate forests. But it is also partly
composed of shrublands, temperate grasslands and savannas.
■ Tasmania is mostly composed of temperate forests.
■ New Guinea contains tropical forests.

9. Some biomes of the Australian region (top left to bottom right) – desert, temperate rainforest, tropical
rainforest, swamp and snow covered mountains.

10. VERTEBRATE FAUNA
■ The Australian region has a huge number of endemic animal species, i.e.
they are not found anywhere else in the world.
■ Most of this endemic fauna is very primitive in comparison to that of the rest
of the world.
■ This region is also referred to as the “veritable museum of archaic animals”.

12. FRESHWATER FISH
■ Freshwater fish fauna is primitive.
■ Queensland Lungfish (Neoceratodus frosteri) and osteoglossids (Arowana) are
unique fish species of the Australian region.
■ A lot of other species such as bass, perches, catfish, etc. are also found here.
■ For its land-size, Australia has a low diversity of native freshwater fish with only 280
described species. This is largely because Australia is a very dry continent with
sporadic rainfall and large areas of desert.

13. FRESHWATER FISH
Queensland lungfish (Neoceratodus frosteri)
■ Endemic to Australia.
■ Neoceratodus has remained virtually
unchanged for well over 100 million years.
■ It inhabits mud, sand or gravel bottoms. It
is a sluggish species that prefers still or
slow-flowing waters, usually in deep pools.
■ It can live for several days out of the water,
if it is kept moist, but will not survive total
water depletion.
■ It is a facultative air-breather that will die if
forced to depend on air breathing.
■ It is nocturnally active and feeds on frogs,
tadpoles, fishes, shrimp, earthworms,
snails, aquatic plants and native fruits
fallen from trees overhanging the creeks.
Queensland lungfish (Neoceratodus frosteri)

14. FRESHWATER FISH
Arowanas
■ These are freshwater bony fish of the
family Osteoglossidae.
■ They are also known as bonytongues
(because of a toothed bone on the floor of
the mouth equipped with teeth that bite
against teeth on the roof of the mouth).
■ It is a facultative air breather and can
obtain oxygen from air by sucking it into its
swim bladder.
■ They are carnivorous, often being
specialized surface feeders.
■ They can leap more than 6 feet from the
water surface to pick off insects and birds
from overhanging branches.
■ They grow around 2 to 3 feet in captivity.
Australian Arowana (Scleropages jardinii)

15. FRESHWATER FISH
Australian bass (Macquaria
novemaculeata)
■ It is a small to medium-sized,
primarily freshwater (but estuarine
spawning) species of fish.
■ It is found in coastal rivers and
streams along the east coast of
Australia.
■ Australian bass is an important
member of the native fish
assemblages found in east coast
river systems.
■ It is a predatory native fish.
■ It is an extremely popular angling
species. Australian Bass (Macquaria novemaculeata)

16. AMPHIBIAN FAUNA
■ It is the only region where the common toad is not naturally found.
■ Although an invasive species – the Cane Toad, was introduced.
■ Frogs and tree frogs are present.
■ Tailed amphibians (newts and salamanders) and caecilians are absent.

17. AMPHIBIAN FAUNA
Leaf Green Tree Frog (Litoria
phyllochroa)
■ It is a species of stream-dwelling
frog, native to eastern Australia.
■ This is a fairly small species of tree
frog, up to about 40 mm in length.
■ It can be light green to dark olive
green to light brown to dark brown
on the dorsal surface.
■ The toes are three-quarters webbed
and toe discs are large.
■ The belly is white.
Leaf Green Tree Frog (Litoria phyllochroa)

18. AMPHIBIAN FAUNA
Cane Toad (Rhinella marina) – Introduced
/ Invasive Species
■ It is a large, terrestrial true toad
native to South and mainland Central
America.
■ It has been introduced to various
islands throughout Oceania and the
Caribbean, as well as Northern
Australia.
■ It is the world's largest toad.
■ It has poison glands.
■ The tadpoles are highly toxic to most
animals if ingested.
■ Its toxic skin can kill many animals.
■ It has disturbed the native ecology of
Australia.
Cane Toad (Rhinella marina)
MALE
FEMALE

19. REPTILIAN FAUNA
■ This region includes some exclusive families of reptiles such as:
1. Carettochelyidae – pig nosed turtles / pitted shell turtles
2. Pygopodidae – legless / flap-footed lizards
3. Sphenodontidae – which has only one member – Tuatra, confined to New Zealand
■ Lizards such as Varanus spp. (monitor lizards – most notably the Komodo dragon),
geckos and agamids are found here.
■ Snake species include typhlops (blind snakes), pythons, cobras and elapsids (among
many others).
■ Two species of crocodiles (the aggressive salt-water and passive fresh-water crocodiles)
are also present.

20. REPTILIAN FAUNA
Tuatara (Sphenodon puctatus)
■ It is a reptile endemic to New Zealand.
■ It is a part of the order Rhynchocephalia.
■ It is the only surviving member of its order,
which flourished around 200 million years ago.
■ Tuataras are referred to as “living fossils”.
■ Some of their unique properties include:
1. They have two rows of teeth in the upper jaw
overlapping one row on the lower jaw.
2. They have a “third / parietal eye” (on the top
of their head, it is distinctly visible when they
are young), which is thought to be involved in
setting circadian and seasonal cycles.
3. They are able to hear, although no external
ears are present.
Tuatara (Sphenodon punctatus)
MALE
FEMALE

21. REPTILIAN FAUNA
Komodo dragon (Varanus komodoensis)
■ It is a species of lizard found in the
Indonesian islands of Komodo, Rinca,
Flores, and Gili Motang.
■ It is the largest living species of lizard.
■ These lizards dominate the ecosystems in
which they live.
■ They hunt and ambush prey including
invertebrates, birds, and mammals.
■ The diet of big Komodo dragons mainly
consists of Timor deer, though they also eat
considerable amounts of carrion (decaying
meat of dead animals).
■ Komodo dragons also occasionally attack
humans. Komodo dragon (Varanus komodoensis)
MALE
FEMALE

22. REPTILIAN FAUNA
Burton's Legless Lizard (Lialis burtonis)
■ It is a species of legless lizard (also known
as flap-footed lizard) in the family
Pygopodidae.
■ The species lacks forelegs and has only
rudimentary hind legs.
■ This species is endemic to Australia and
Papua New Guinea.
Burton's Legless Lizard (Lialis burtonis)
MALE
FEMALE

23. REPTILIAN FAUNA
Pig-nosed Turtle (Carettochelys insculpta)
■ It is also known as the pitted-shelled turtle
or Fly River turtle.
■ It is native to northern Australia and
southern New Guinea.
■ It is unlike any other freshwater turtle.
■ The feet are flippers, resembling those of
marine turtles.
■ The nose looks like that of a pig, having the
nostrils at the end of a fleshy snout, hence
the common name.
■ The carapace is typically grey or olive, with a
leathery texture.
■ The plastron is cream-colored.
Pig-nosed Turtle (Carettochelys insculpta)
MALE
FEMALE

24. REPTILIAN FAUNA
Diamond Python (Morelia spilota)
■ It is a large (non-venomous) constrictor snake
of the family Pythonidae.
■ It is found in Australia, New Guinea, Bismarck
Archipelago, and the northern Solomon
Islands.
■ It is a large species of python.
■ Males are typically smaller than females.
■ The head is triangular.
■ The coloring is highly variable, ranging from
olive to black with white or cream and gold
markings.
■ The patterning may be roughly diamond-
shaped or have intricate markings made up
of light and dark bands on a background of
gray or a version of brown.
Diamond Python (Morelia spilota)
MALE

25. REPTILIAN FAUNA
Saltwater Crocodile (Crocodylus porosus)
■ It is a crocodilian populating the brackish
and freshwater regions of eastern India,
Southeast Asia, and northern Australia.
■ They are excellent swimmers and have often
been spotted far out at sea.
■ It is among the largest crocodiles.
■ It ambushes most of its prey and then
drowns or swallows it whole.
■ It is capable of prevailing over almost any
animal that enters its territory, including
other apex predators such as sharks.
■ It is well known for its aggressive attacks on
humans.
Saltwater Crocodile (Crocodylus porosus)

26. AVIAN FAUNA
■ The Australian region is rich in its bird fauna.
■ Parrots and pigeons are present.
■ It is famous for ratites (flightless birds without a keel on their sternum bone) like:
1. Emus (Australia)
2. Cassowaries (New Guinea)
3. Kiwis (New Zealand).
■ King fishers, honey-eaters, bowerbirds and birds of paradise are also common.

27. AVIAN FAUNA
Emu (Dromaius novaehollandiae)
■ It is the second-largest living bird by height,
after its ratite, the ostrich.
■ It is endemic to Australia where it is the
largest native bird.
■ Emus are soft-feathered, brown, flightless
birds with long necks and legs.
■ Emus can travel great distances, and when
necessary can sprint at 50 km/h (31 mph).
■ They forage for a variety of plants and
insects, but have been known to go for
weeks without eating.
■ They drink infrequently, but take in copious
amounts of water when the opportunity
arises. Emu (Dromaius novaehollandiae)

28. AVIAN FAUNA
Cassowaries (genus Casuarius)
■ These are ratites that are native to the
tropical forests of New Guinea, East Nusa
Tenggara, the Maluku Islands, and
northeastern Australia.
■ Cassowaries feed mainly on fruit.
■ Although all species are truly omnivorous
and will take a range of other plant food,
including shoots and grass seeds, in
addition to fungi, invertebrates, and small
vertebrates.
■ If provoked they are capable of inflicting
serious injuries, occasionally fatal, to dogs
and people.
■ It is often referred to as “the world's most
dangerous bird”.
Cassowaries (genus Casuarius)
ADULT
JUVENILE

29. AVIAN FAUNA
Kiwis (genus Apteryx)
■ They are flightless birds native to New
Zealand.
■ Approximately the size of a domestic
chicken, kiwi are by far the smallest living
ratites.
■ The kiwi's egg is one of the largest in
proportion to body size (up to 20% of the
female's weight) of any species of bird in the
world.
■ Other unique adaptations of kiwi, such as
their hair like feathers, short and stout legs,
and using their nostrils at the end of their
long beak to detect prey before they even
see it, have helped the bird to become
internationally well-known.
Kiwis (genus Apteryx)

30. AVIAN FAUNA
Bowerbirds (family Ptilonorhynchidae)
■ They are renowned for their unique
courtship behavior, where males build a
structure and decorate it with sticks and
brightly colored objects in an attempt to
attract a mate.
■ These are medium to large-sized
passerines, their diet consists mainly of fruit
but may also include insects (especially for
nestlings), flowers, nectar and leaves in
some species.
■ They occupy a range of different habitats,
including rainforest, eucalyptus and acacia
forest, and shrublands.
Golden bowerbird, Great bowerbird and
Tan-capped catbird

31. MAMALIAN FAUNA
■ Australian region is famous for its primitive mammals.
■ Placental mammals are absent, except for those which were later introduced by man.
■ Egg laying mammals (Subclass Prototheria) have one order – Monotremata (monos –
“single” and trema – “hole”, referring to the cloaca), of which two families are present:
1. Tachyglossidae (Echidna – spiny anteaters)
2. Ornithorhynchidae (Ornithorhynchus anatinus – Platypus)
■ The Australian region is also the real home of marsupials, although they are also found
in the Americas (North, Central and South), i.e. opposums.
■ The basic character of marsupial mammals is the presence of a pouch / marsupium in
females where the babies are carried and nourished by a duct from the mammary
glands.
■ Examples of marsupials include kangaroos, wallabies, thylacines, koalas, etc.

32. MAMALIAN FAUNA
Platypus (Ornithorhynchus anatinus)
■ It is sometimes referred to as the duck-
billed platypus.
■ It is a semiaquatic egg-laying mammal
endemic to eastern Australia, including
Tasmania.
■ It is one of the five extant species of
monotremes (the only mammals that lay
eggs instead of giving birth to live young).
■ It senses prey through electrolocation.
■ It is one of the few species of venomous
mammals, as the male platypus has a spur
(spike) on the hind foot that delivers a
venom capable of causing severe pain to
humans. Platypus (Ornithorhynchus anatinus)

33. MAMALIAN FAUNA
Echidnas (family Tacchyglossidae)
■ They are sometimes known as spiny
anteaters.
■ They belong to the monotreme order of egg-
laying mammals.
■ The diet of some species consists of ants
and termites.
■ They are not closely related to the true
anteaters of the Americas, along with sloths
and armadillos.
■ Echidnas live in Australia and New Guinea.
■ They evolved between 20 and 50 million
years ago, descending from a platypus-like
monotreme. This ancestor was aquatic, but
echidnas adapted to life on land. Short-beaked Echidna, Western Long-beaked Echidna
and Eastern Long-beaked Echidna

34. MAMALIAN FAUNA
Koala (Phascolarctos cinereus)
■ It is an arboreal herbivorous marsupial
native to Australia.
■ It is easily recognizable by its stout, tailless
body and large head with round, fluffy ears
and large, spoon-shaped nose.
■ Pelage color ranges from silver grey to
chocolate brown.
■ Koalas typically inhabit open eucalypt
woodlands, and the leaves of these trees
make up most of their diet.
■ Koalas are largely sedentary and sleep up
to 20 hours a day.
■ They are asocial animals, and bonding
exists only between mothers and dependent
offspring.
Koala (Phascolarctos cinereus)

35. MAMALIAN FAUNA
Kangaroos (family Macropodidae)
■ These are the largest species from their
family, especially those of the genus
Macropus (smaller members of this
family are referred to as wallabies and
wallaroos).
■ Kangaroos are indigenous to Australia.
■ Kangaroos have large, powerful hind legs,
large feet adapted for leaping, a long
muscular tail for balance, and a small
head.
■ Like most marsupials, female kangaroos
have a pouch called a marsupium in
which joeys (young ones) complete
postnatal development.
Kangaroos (family Macropodidae)

36. MAMALIAN FAUNA
Thylacine (Thylacinus cynocephalus)
■ Now extinct, it was one of the largest known
carnivorous marsupials.
■ It is commonly known as the Tasmanian tiger
because of its striped lower back, or the
Tasmanian wolf because of its canid-like
characteristics.
■ It was native to Tasmania, New Guinea, and
the Australian mainland.
■ The thylacine was relatively shy and nocturnal.
■ The thylacine was a formidable apex predator.
■ Because of convergent evolution it displayed a
form and adaptations similar to the tiger and
wolf of the Northern Hemisphere, even though
not related.
Thylacine (Thylacinus cynocephalus)

37. BOUNDARY BETWEEN AUSTRALIAN AND
ORIENTAL REGIONS
■ The two main continents of the Australian and Oriental regions are
separated by a string of islands known as the Malayan Archipelago.
■ Of these islands, the western ones belong to the Oriental region while the
eastern ones belong to the Australian region.
■ But the main problem is to decide where to adjust several other smaller
islands in between these larger ones.
■ Several attempts were made to divide these islands between the two
neighboring realms, three most important lines (imaginary) of divisions
proposed by various scientists are as follows:

38. BOUNDARY BETWEEN AUSTRALIAN AND
ORIENTAL REGIONS
1. WALLACE’S LINE
■ It is a faunal boundary line drawn in 1859 by the British naturalist Alfred
Russel Wallace and named by English biologist Thomas Henry Huxley.
■ It separates the Oriental region and Wallacea (a transitional zone between
Asia and Australia).
■ The line runs through Indonesia, according to this line, Java, Borneo,
Mindanao and Bali islands have been given to the Oriental region whereas
Celebes, Sangi, Talaud, Lombok, etc. have been given to the Australian
region.
■ Wallace noticed this clear division during his travels through the East Indies
in the 19th century.

39. BOUNDARY BETWEEN AUSTRALIAN AND
ORIENTAL REGIONS
2. LYDEKKER’S LINE
■ In 1895, Richard Lydekker proposed the Lydekker's line, which separates
Wallacea (west) from Australia and New Guinea (east).
■ It follows the edge of the continental shelf of New Guinea to Australia.
■ Continental shelf is the area around the continent which is submerged under
shallow water.
■ It is the eastern most proposed boundary.

40. BOUNDARY BETWEEN AUSTRALIAN AND
ORIENTAL REGIONS
3. WEBER’S LINE
■ In 1904, Max Carl Wilhelm Webber proposed the Webber’s line.
■ It is a hypothetical boundary that lies approximately along the continental
shelf of Australia and New Guinea.
■ It is based on the molluscan and mammalian fauna of the islands, it is
eastwards from the Wallace’s line and is sometimes preferred over it.

41. BOUNDARY BETWEEN AUSTRALIAN AND
ORIENTAL REGIONS
WALLACEA – THE FINAL SOLUTION
■ The middle islands of the Malayan archipelago have been populated in a
haphazard manner by migrations across the ocean from either side.
■ The fauna of each island has evolved into a unique assemblage which does
not resemble with that of the other islands or the two regions.
■ Hence instead of debating on the validity of either Wallace’s or Webber’s
line, both lines can be accepted and the area between them can be referred
to as a transitional zone (which acts as a boundary) between the two regions
– Wallacea (named in the honor of Alfred Russel Wallace).

42. A map showing Wallace’s line, Webber’s line and Lydekker’s line, separating the Australian and Oriental regions.
Wallacea lies between Wallace’s and Webber’s lines.

43. THANK YOU