THE THYLACINE
SUPER COHORT MARSUPIALIA
COHORT AUSTRALIDELPHIA
FAMILY THYLACINIDAE
The family Thylacinidae comprises only one species,
the thylacine or tasmanian wolf (Thylacinus cynocephalus).
Following
the arrival of Europeans, the thylacine developed a reputation for
killing sheep, and hunting and epidemic disease appear to have brought
about its extinction.
There have been no official
sightings of this animal since the last thylacine in captivity died in
Hobart Zoo in 1936.
Fossils show that the thylacine lineage arose about 15 millions years ago.
The thylacine's dental and pedal morphology was unlike any
other Australian marsupial and it is presumed to be
a sister group to the dasyurids.
The thylacine was the largest of recent marsupials,
weighing between 15 and 35 kg. It was a nocturnal animal, tending
to feed in woodland and
grasslands and nesting in dense forests on
hilly terrain.
Thylacines were thought to have hunted alone or in pairs,
preying upon wallabies, possums, bandicoots, rodents and birds.
Superficially thylacines resembled dogs, about 60 cm
high at the shoulder,
with a dog-like head, short neck, short legs and a long stiff tail. Sandy
yellow in colour, they had brown/black stripes across the back.
They ran on diagonally opposing limbs, sat upright on their tail and
hindlimbs like a kangaroo, and could leap 2 - 3 metres high.
Thylacine skull |
Wolf skull |
The thylacine's long-snouted skull shows remarkable evolutionary
convergence with the
skulls of wolves and dogs but closer inspection reveals typical marsupial
features.
- Thylacines have a relatively small brain case compared to the wolf
- The thylacine's dental formula is I4/3; C1/1; PM3/3; M4/4
- The wolf's dental formula is I3/3; C1/1; PM4/4; M3/3;
- Thylacines lack the carnassial tooth of wolves and dogs;
- The thylacine skull has palatal vacuities, like skulls of primitive
mammals;
- Wolf and dog skulls lack palatal vacuities.
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