Australia's Vanished Beasts
The marsupial lion is just one of
numerous megafauna, or "big animals," that lived in Australia
during the Pleistocene Epoch (1.7 million to 10,000 years ago). All of them are
gone forever, rendered extinct under still mysterious circumstances sometime
after humans first arrived on the continent some 50,000 or 60,000 years ago. In
this slide show, see evocative illustrations of some of these extinct wonders
as they might have appeared when alive, and find out what made them stand
"Few extinct mammals have
aroused so much curiosity, so much conjecture as to their way of life and their
relationship to other forms as the enigmatic marsupial lion," the
paleontologist Rod Wells has written. What Wells and other experts know about
this creature they have gleaned from fossil bones, including the complete
skeleton discovered in 2002 and featured in "Bone Diggers." Despite
its name, T. carnifex was no lion. It
raised its young in a pouch, like all marsupials, and its anatomy suggests it
was built for dropping onto prey animals from trees rather than chasing them
down. Once it grabbed hold of a victim, with help from its large, clawed thumb,
the marsupial lion may have dragged it into a tree (as shown here) to devour it.
This was the first fossil mammal
from Australia given a name (in 1838). Meaning "two forward teeth,"
Diprotodon featured two incisors that
jutted straight out from its upper jaw, giving it a buck-toothed look. It may
have sported a trunk as well, though experts will never be sure unless they
turn up a mummified carcass (like the dessicated remains of giant ground sloths
found in caves in the Americas) or perhaps unequivocal rock drawings by ancient
Aborigines, who are known to have lived alongside diprotodontids for at least
10,000 years. From its teeth, experts have determined that the plant-eating Diprotodon was a browser. Here, a mother watches helplessly as
its infant bogs down in mud on the edge of a drying lake.
This animal has been deemed
"among the most unusual mammals ever to have lived." It bore
massive forearms with impressive claws, which it may have used to rip bark from
trees, as seen here. The palorchestids may
have been the Australian equivalent of the giant ground sloths of the Western
Hemisphere. Their remains have turned up only in eastern coastal Australia,
which today has extensive wet and dry forests; indeed, this animal may have
been confined to woodlands. The shape and positioning of the nasal bones in its
skull suggest it had a trunk, though, again, experts can't be certain.
The palorchestids have no modern analogues—when they went extinct, their
In 1873, working only from
fragments of skulls and jaws, the British comparative anatomist Sir Richard
Owen named this genus of kangaroo Sthenurus,
meaning "strong-tailed beast." Owen was prescient, for a century
later when full skeletons were uncovered, this creature was revealed to have a
tail stronger and shorter relative to body size than that of all living
kangaroos. Its anatomy and teeth suggest it was a large, leaf-eating ‘roo
that walked almost exclusively on its monodactyl ("one-toed") hind
feet. The only survivor of its lineage may be the banded hare-wallaby, which
survives on only two small islands off the coast of Western Australia.
Giant Rat Kangaroo
One of the rarest and least
understood of the extinct Pleistocene marsupials is the giant rat kangaroo,
which is known from fewer than 20 individual specimens, most of them represented by jaw bones. Its
jaw and teeth are similar to those of the living musky rat kangaroo, but,
befitting its megafaunal status, it was much larger, weighing up to 150 pounds
compared to the roughly 18 pounds of its surviving cousin. Based on its
dentition, experts have suggested that it may have been both a meat- and
plant-eater. Like the baboon, for instance, it may have been an opportunistic
feeder that dined on meat, eggs, insects, and vegetation. Here, a giant rat
kangaroo devours emu eggs.
You would not want to have run into
a hungry giant goanna. For one thing, its kind was huge: experts have estimated
that the largest M. prisca for which
there is some fossil evidence was 23 feet long and weighed about 1,350 pounds.
That's about eight times the mass of the living Komodo dragon, which the
giant goanna may have resembled in basic ecology and behavior. Like the Komodo,
it may have lurked in undergrowth before ambushing prey—such as the
diprotodontid downed at a waterhole in this illustration—then ripped
apart its victim with its large, serrated teeth. (Its genus name means
In 1970, deep inside
Australia's Tea Tree Cave, a caver discovered a skull lying upside down
on the cavern floor. It turned out to be from a large, previously unknown
crocodilian. The reptile resembled an extinct type of croc called a ziphodont,
whose snouts were both broad and deep. (The snouts of most of today's
crocs are broader than they are deep.) The caver's find was subsequently
named after the "quinkans," mythical humanoids of the Dreamtime,
the creation time in Aboriginal mythology. Growing to perhaps 10 feet in
length, the land-based quinkan was one of the largest carnivores of the Australian
Pleistocene and probably was capable, like the giant goanna, of taking down the
largest marsupials, including diprotodontids.
Giant Australian Python
The longest surviving snake in
Australia today is the carpet python, which grows to not much longer than 10
feet in length. The extinct giant Australian python, by contrast, was thought
to reach over 16 feet long. It is similar to other extinct giant boids from
Patagonia, Madagascar, and northern Africa, suggesting they all shared a common
ancestor when the southern continents were attached to one another in the
ancient supercontinent Gondwana. Much remains unknown about W.
naracoortensis, however. Did it lay eggs or
give birth to live young? How widely was it distributed? How long did it live
on Earth? Future fossil discoveries may tell.
This giant flightless bird compared
in size to the biggest of New Zealand's extinct moas and
Madagascar's extinct elephant birds—the largest birds that ever
lived. But anatomically it is different from all other birds, including
Australia's living emus. Altogether, at least six genera and eight
species of mihirungs—which are commonly known as thunderbirds—lived in Australia in the past 15
million years; all are extinct. What role humans might have played in their
extinction remains unknown, although people and mihirungs did overlap.
Indeed, one Aboriginal tribe had a name for "giant emus"—mihirung
paringmal. Here, a mihirung collects pebbles from a Genyornis carcass; the swallowed pebbles help break down food.
"Giant" is relative
here—this bird was simply bigger than all existing coucals, which are
members of the cuckoo family. The giant coucal probably spent most of its time
on the ground, feeding on insects, amphibians, and lizards. Perhaps only in
emergencies, such as during an attack by a predator, would it take flight, likely
in short, labored bursts—all its smallish wings could provide. This
illustration shows the giant coucal in breeding (top) and nonbreeding plumage,
though it's entirely speculative; no one knows the actual color of its plumage. Like so much about the vanished Australian megafauna, answers may lie
in fossils still unfound, awaiting discovery and analysis by paleontologists.
Note: Illustrations by Frank Wright
for the book Kadimakara: Extinct Vertebrates of Australia, edited by P. V. Rich and G. F. van Tets (1st
edition Pioneer Desgin Studio, 1985; 2nd edition Princeton University Press,
1991). Used with kind permission of editor and writer P. Vickers Rich.
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