Midway through the program, Dr. Frank Carrick of the Department of Zoology at UQ provided a lecturs on Australian on marsupial biology with a special emphasis on koalas and the reproductive adaptions of these animals. Dr. Carrick's lecture was given at the University of Queensland Vet Farm in Pinjarra Hills, about a 15 minute ride from the main campus at St. Lucia.
After the lecture, we were able to have a first hand look at the Koala Study program run at the Vet Farm by Dr. Carrick. Among other things, the program cares for koalas that have suffered injuries (usually from encounters with cars or dogs) or that are ill with some other disease.
"Bertie" and Dr. Carrick.
|Sub-class Prototheria||Sub-class Metatheria||Sub-class Eutheria|
|Order Monotremata||Order Diprotodonta||Order Carnivora|
|Order Polyprotodonta||Order Cetacea|
There are also several feral mammals (including camels, cats dogs, donkeys, hares, horses, pigs, and rabbits) with populations established in the wild, but these will not be considered in the notes that follow.
Eutherians: Many of the native eutherian mammals are very interesting. They include the following species: Dugong, Coconut Rat, Giant Rabbit Rat, Water Rat, Flying Foxes, and Ghost Bat.
Monotremes: There are three kinds of living monotremes: Platypus, Short-beaked Echidna, and Long-beaked Echidna (now only found in New Guinea). Although their best known feature is egg laying, they have other unique features such as electro-receptors in their snouts and the males have poison spurs on their heels.
Marsupials: Although biology textbooks often talk about marsupials as being primitive animals, this is quite untrue. For example, Kangaroos have evolved fairly recently and have the most sophisticated lactational physiology and temperature regulation known fora ny mammal. Most of the characteristics which distinguish marsupials are reproductive or embryological. A major characteristic is that they produce very small young after a short pregnancy, which is less than the length of the oestrous cycle.
Kangaroo adaptations to the unpredictable Australian environment include postpartum oestrus (a female can mate two or three days after giving birth) and embryonic diapause (after mating fertilization occurs, the embryo can remain viable in the uterus for many months without any development). The cue for the embryo to develop is when the young in the pouch stops suckling and becomes a young at foot. So most of the time, a female will be looking after three young: one at foot, one in the pouch, and one on "pause" in the uterus. If times are bad and food is scarce, the pouch young may die. But another will be ready to go as soon as conditions improve.
The Australian marsupials can be subdivided into two major groups on the basis of their dentition: polyprotodonts, which are mostly carnivores and insectivores, and diprotodonts, which are mostly omnivores and herbivores. There is a great diversity of marsupials. Even though there are no "marsupial bats" or "marsupial whales," virtually every other mammalian lifestyle has been evolved by marsupials now or in the past.
|Common Planigale, Common Dunnart, Brown Antechinus, Yellow-footed Antechinus||Pygmy Possum, Feahtertail Glider, Sugar Glider|
|Numbat, Kowari, Phascogale, Tiger Quoll, Long-nosed Bandicoot, Brown Bandicoot, Bilby||Squirrel Glider, Fluffy Glider, Greater Glider, Common Ringtail Possum, Green Ringtail Possum, Herbert River Ringtail, Common Brushtail Possum, Rufous Bettong, Potoroo, Brush-tail Rock Wallaby|
|Tasmanian Devil, Thylacine||Koala, Northern Hairynosed Wombat, Red-legged Pademelon, Yellow-footed Rock Wallaby, Red necked Wallaby, Swamp Wallaby, Wallaroo, Eastern Grey Kangaroo, Red Kangaroo|
Class: Mammalia Subclass: Theria Infraclass: Metatheria Order: Marsupialia Species: Thrichosurus vulpecula "Common Brushtail Possum"The common brushtail possum is a medium sized diprotodont with a body length of 500 mm, tail length of 380 mm, and a weight of 4 kg. They are the most commonly encountered Brisbane marsupial. They are nocturnal and are found in either wet or dry forests.
(Photo taken on the UQ campus.)
Class: Mammalia Subclass: Theria Infraclass: Methatheria Order: Marsupialia Species: Pseudocheirus peregrinus "Common Ringtail Possum"The common ringtail possum is another medium sized diprotodont with a body length of 350 mm, tail length of 350 mm, and a weight of 4 kg. They are common even in inner city suburbs, parks, along watercourses, and in backyard gardens. They are nocturnal and feed on flowers or leaves.
(Photo taken on
the UQ campus.)
Class: Mammalia Subclass: Theria Infraclass: Methatheria Order: Marsupialia Species: Thylogale thetis "Red-necked Pademelon"The red-necked pademelon is a somewhat larger diprotodont with a body length of 500 mm, tail length of 400 mm, and a weight of 6 kg. They are common in restricted habitats of rainforest and vine thickets. They are nocturnal and because they graze on grass they are encountered more frequently than most other pademelons.
(Photo taken at Lamington National Park.)
Class: Mammalia Subclass: Theria Infraclass: Methatheria Order: Marsupialia Species: Macropus agilis "Agile Wallaby"The agile wallaby is a larger diprotodont with a body length of 80 cm, tail length of 77 cm, and a weight of 15 kg. They are uncommon and perhaps dying out. They are found in dry open forests, heath, and adjoining grasslands.
(Photo taken at South Stradbroke Island.)
Class: Mammalia Subclass: Theria Infraclass: Methatheria Order: Marsupialia Species: Wallabia bicolor "Swamp Wallaby"Body , tail The swamp wallaby has a body length of 66-85 cm, tail length of 64-86 cm, and a weight of 15 kg. They are very dark with a charcoal back, a black "mask" with a yellowish face stripe, and black feet. They are reasonably common and may be found in not only in swamps and gullies, as their name would indicate, but also in open forests, heathlands and along shrubby waterways.
(Photo taken at South Stradbroke Island.)
Class: Mammalia Subclass: Theria Infraclass: Methatheria Order: Marsupialia Species: Macropus gigantus "Grey Kangaroo"The grey kangaroo is a large diprotodont with a body length of 1 m, tail length of 90cm, and a weight of 50 kg. They are uniform woolly grey-brown with a black-tipped tail. They are now uncommon.
(Photo taken at 18-Mile Swamp, North Stradbroke Island.)
Class: Mammalia Subclass: Theria Infraclass: Methatheria Order: Marsupialia Species: Phasolarcotis cinerus "Koala"The koala is a somewhat larger diprotodont with a body length of 90cm and a weight of 6kg. It is not commonly seen in the greater Brisbane area. Its nocturnal and feed mainly on the leaves of certain gum trees. Dogs, cars and guns are the main threats. In two six-month visits, the only koalas in the wild I saw were at Noosa, 200km north of Brisbane.
(Photo taken at UQ Vet Farm in Pinjarra Hills.)
Class: Mammalia Subclass: Theria Infraclass: Eutheria Order: Cetacea Species: Tusiops truncatus "Bottle-nose Dolphin"Mature adults reach 2 to 2.5 m in length. Body fairly robust and light grey. Dorsal fin recurved at back. Most common dolphin in Moreton Bay with a population estimated to be in excess of 350.
(Photo taken at Point Lookout, North Stradbroke Island.)