Kinds of specimens
- Introduction
- Mounted skins
- Study skins
- Skulls
- Skeletons
- Teeth
- Spirit specimens
- Spirit organs
- Frozen tissues
- Parasites
- Baleen
- Owl pellets
- Trophies
Introduction
The Mammal collection is made up of different types of specimens including mounted skins, 'study' skins, skulls, skeletons, whole animals or organs preserved in spirit and parts of animals such as teeth or baleen. Each type of specimen has a range of uses and storage requirements.
The collection contains representatives from almost all of the mammal genera in the Australia Pacific region with particular emphasis on species found within New South Wales. Approximately 400 specimens in the collections are 'types', the original specimen or series of specimens on which a particular species was described. Other historically important specimens include those of species that are now extinct, such as the Pig-footed Bandicoot, Chaeropus ecaudatus, Crescent Nailtail Wallaby, Onychogalea lunata, Lesser Bilby, Macrotis leucura, Broad-faced Potoroo, Potorous platyops, Thylacine, Thylacinus cynocephalus and Long-tailed Hopping Mouse, Notomys longicaudatus, as well as specimens collected by early explorers.
Mounted skins
The most familiar and certainly the most lifelike types of specimens are mounted skins. These are generally used for educational purposes, particularly for display in exhibitions or for teaching. Mounts make up only a small percentage of the collection as they take up more space than study skins and are easily damaged.
This mounted lion skin has been prepared in a lifelike pose for display.
Mounted skin of a Short-beaked Echidna, Tachyglossus aculeatus.
Study skins
A large part of the collection is made up of 'study' skins. Study skins are mainly prepared for scientific reference but also reduce the risk of damage and storage space needed. Like mounts, study skins have had all the internal organs and most of the skeleton removed and replaced with an inert material such as cotton or straw.
These Northern Quoll, Dasyurus hallucatus study skins are used mainly for research. Study skins are easier and cheaper to prepare than mounted skins, take up less space and are less likely to be damaged during handling and storage.
Study skin of Gould's Long-eared Bat, Nyctophilus gouldi.
Skulls
Skulls are one of the most intensively used parts of the Mammal collection and are particularly useful for identification purposes. These have usually been prepared by 'maceration', a technique that involves immersing the skull in water and allowing the flesh to rot. Some skulls have been prepared by allowing colonies of small beetles (dermestids) to eat off the flesh.
Some of the smallest and most fragile items in the Mammal collection are the skulls of microchiropteran bats such as this Gould's Wattled Bat, Chalinolobus gouldii measuring less than 1cm in length.
One of the largest specimens in the Mammal collection is this skull of a Bryde's whale, Balaenoptera edeni obtained from an animal that stranded on the south coast of New South Wales in 1989.
Skull of a Rousette Bat, Rousettus amplexicaudatus, a small flying fox found in New Guinea, Solomon Islands and south-east Asia.
Skeletons
Skeletons are another scientifically important part of the Mammal collection. A few skeletons have been reassembled or 'articulated' for educational purposes and some of these can be seen on display in the Skeleton exhibition. However, a much larger number of skeletons are stored as unarticulated bones, each individual bone being marked with the specimen's unique registration number.
This skeleton of a Grey-headed Flying Fox, Pteropus poliocephalus has been articulated for display in a museum exhibition on bats. It shows some of the adaptations of the bat skeleton for flight such as the elongated bones of the hand to form the wing and the small pelvis.
These articulated (reconstructed) skeletons of placental mammals such as the hyaena, dingo and fox are on display in the Skeleton exhibition. Most skeletons in the Mammal collection are stored unarticulated as this is more useful to researchers.
Teeth
The Mammal collection also contains individual teeth from a range of species including some of the larger toothed whales such as the Sperm Whale, Physter macrocephalus (sailors once used their teeth for carvings known as scrimshaw) and narwhals, as well as exotic species such as hippopotamus and elephant.
Spirit specimens
A large part of the collection comprises whole animals stored in alcohol. These types of specimens are particularly important for scientific study as many of the diagnostic features (such as ears, tails and feet) are still intact and the internal organs such as stomach and reproductive system have not been removed.
Nearly half the Mammal collection consists of whole animals preserved in ethanol like these juvenile Bandicoots, Echymipera kalubu from New Guinea. In spirit-preserved specimens most internal organs are preserved largely intact and so are used for a diverse range of research studies.
Spirit specimen of a Northern Quoll, Dasyurus hallucatus.
Brain of a baleen whale, Balaeonoptera sp. preserved in formalin.
Spirit organs
A small part of the collection consists of organs preserved in ethanol or formalin. These organs can be used for a range of studies including examining diet, reproduction, development and disease.
Frozen tissues
Samples of muscle, liver and other tissues taken from mammal specimens are transferred to the Evolutionary Biology Unit where they become part of the Museum's frozen tissue collection.
Small samples of tissue such as muscle, liver, heart or kidney are taken from specimens as they are being prepared. Samples are either frozen or preserved in ethanol as part of the Museum's tissue collection. These become the basis for a wide range of evolutionary studies based on DNA extracted from the tissues.
Parasites
Many mammal species host a variety of internal and external parasites that can be removed and preserved in ethanol. Some examples of these are bat flies (a highly specialised group of wingless flies) from bats, ticks from marsupials and tapeworms from whales and dolphins. These specimens are transferred to the appropriate Australian Museum Collection.
Baleen
Small sample of baleen from a Pygmy Right Whale, Caperea marginata.
The fringed plates, known as baleen, that hang from the roof of the mouth of baleen whales (mysticetes) such as Humpback, Megaptera novaeangliae and right whales, also form a small part of the Mammal collection. These triangular shaped plates that vary in number, size and colour between species, are used to filter krill and other small prey from the water.
Owl pellets
Tiny skulls or bone fragments recovered from regurgitated owl pellets often reveal the presence of species not detected using other wildlife survey techniques. Some samples sent in to the Museum are evidently over 50 years old as they contain remains of species that are now extinct in New South Wales.
Owls regurgitate some of the most indigestible parts of their meals and these pellets, often filled with fur and bones, are occasionally preserved for many years in caves and other rock overhangs. Collections of owl pellet material have recently been donated to the Museum. Because these may be more than 50 years old, they sometimes contain scientifically valuable items including the skulls and skeletons of species that are now either locally or totally extinct.
Trophies
Another source of valuable skull and skeletal material are the cooking fires or homes of people who rely on native mammals as a source of food. These specimens, mostly from New Guinea, are often discoloured or broken but represent a unique opportunity to acquire a broad range of marsupial, bat and rodent species from this part of the Pacific.
Copyright © Australian Museum, 2003
