HOME

TheInfoList



OR:

The short-beaked echidna (''Tachyglossus aculeatus''), also called the short-nosed echidna, is one of four living species of
echidna Echidnas (), sometimes known as spiny anteaters, are quill-covered monotremes (egg-laying mammals) belonging to the family Tachyglossidae . The four extant species of echidnas and the platypus are the only living mammals that lay eggs and the ...
and the only member of the genus ''Tachyglossus''. It is covered in fur and spines and has a distinctive snout and a specialized
tongue The tongue is a muscular organ (anatomy), organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive system, digestive process, and is the primary organ of taste. The tongue's upper surfa ...
, which it uses to catch its insect prey at a great speed. Like the other extant monotremes, the short-beaked echidna lays
eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...
; the monotremes are the only living group of
mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s to do so. The short-beaked echidna has extremely strong front limbs and claws, which allow it to burrow quickly with great power. As it needs to be able to survive underground, it has a significant tolerance to high levels of
carbon dioxide Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...
and low levels of
oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
. It has no weapons or fighting ability but repels
predators Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
by curling into a ball and deterring them with its spines. It lacks the ability to sweat and cannot deal with heat well, so it tends to avoid daytime activity in hot weather. It can swim if needed. The snout has
mechanoreceptor A mechanoreceptor, also called mechanoceptor, is a sensory receptor that responds to mechanical pressure or distortion. Mechanoreceptors are innervated by sensory neurons that convert mechanical pressure into electrical signals that, in animals, ...
s and
electroreceptors Electroreception and electrogenesis are the closely-related biological abilities to perceive electrical stimuli and to generate electric fields. Both are used to locate prey; stronger electric discharges are used in a few groups of fishes to st ...
that help the echidna to detect its surroundings. During the
Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
n winter, it goes into deep
torpor Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time ...
and hibernation, reducing its
metabolism Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...
to save energy. As the temperature increases, it emerges to
mate Mate may refer to: Science * Mate, one of a pair of animals involved in: ** Mate choice, intersexual selection ** Mating * Multi-antimicrobial extrusion protein, or MATE, an efflux transporter family of proteins Person or title * Friendship ...
. Female echidnas lay one egg a year and the mating period is the only time the otherwise
solitary animals Sociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies. Sociality is a survival response to evolutionary pressures. For example, when a mother was ...
meet one another; the male has no further contact with the female or his offspring after mating. A newborn echidna is the size of a
grape A grape is a fruit, botanically a berry, of the deciduous woody vines of the flowering plant genus ''Vitis''. Grapes are a non- climacteric type of fruit, generally occurring in clusters. The cultivation of grapes began perhaps 8,000 years ago, ...
but grows rapidly on its mother's milk, which is very rich in nutrients. Baby echidnas eventually grow too large and spiky to stay in the pouch and, around seven weeks after hatching, are expelled from the pouch into the mother's burrow. At around six months of age, they leave the burrow and have no more contact with their mothers. The species is found throughout Australia, where it is the most widespread native mammal, and in coastal and highland regions of eastern
New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...
, where it is known as the ''mungwe'' in the Daribi and Chimbu languages.Flannery, T. 1990. ''Mammals of New Guinea'' Robert Brown & Associates It is not threatened with extinction, but human activities, such as hunting,
habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
, and the
introduction Introduction, The Introduction, Intro, or The Intro may refer to: General use * Introduction (music), an opening section of a piece of music * Introduction (writing), a beginning section to a book, article or essay which states its purpose and g ...
of foreign predatory species and parasites, have reduced its distribution in Australia.


Taxonomy and naming

The short-beaked echidna was first described by
George Shaw George Shaw may refer to: * George Shaw (biologist) (1751–1813), English botanist and zoologist * George B. Shaw (1854–1894), U.S. Representative from Wisconsin * George Bernard Shaw (1856–1950), Irish playwright * George C. Shaw (1866–196 ...
in 1792. He named the
species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
''Myrmecophaga aculeata'', thinking that it might be related to the
giant anteater The giant anteater (''Myrmecophaga tridactyla'') is an insectivorous mammal native to Central and South America. It is one of four living species of anteaters, of which it is the largest member. The only extant member of the genus ''Myrmecophag ...
. Since Shaw first described the species, its name has undergone four revisions: from ''M. aculeata'' to ''Ornithorhynchus hystrix'', ''Echidna hystrix'', ''Echidna aculeata'' and finally, ''Tachyglossus aculeatus''. The name ''Tachyglossus'' means "quick tongue", in reference to the speed with which the echidna uses its tongue to catch ants and termites, and ''aculeatus'' means "spiny" or "equipped with spines".Augee, Gooden and Musser, p. 5. The short-beaked echidna is the only member of its
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
, sharing the family Tachyglossidae with the extant species of the genus ''
Zaglossus The long-beaked echidnas (genus ''Zaglossus'') make up one of the two extant genus, genera of echidnas, spiny monotremes that live in New Guinea; the other being the short-beaked echidna. There are three living species and one extinct species in ...
'' that occur in New Guinea. ''Zaglossus'' species, which include the western long-beaked, Sir David's long-beaked and eastern long-beaked echidnas, are all significantly larger than ''T. aculeatus'', and their diets consist mostly of worms and grubs rather than ants and termites. Species of the Tachyglossidae are egg-laying mammals; together with the related family
Ornithorhynchidae The Ornithorhynchidae are one of the two extant families in the order Monotremata, and contain the platypus and its extinct relatives. The other family is the Tachyglossidae, or echidnas. Within the Ornithorhynchidae are the genera '' Monotrem ...
, they are the only extant monotremes in the world.Augee, Gooden and Musser, p. 10. The five subspecies of the short-beaked echidna are each found in different geographical locations. The subspecies also differ from one another in their hairiness, spine length and width, and the size of the grooming claws on their hind feet.Augee, Gooden and Musser, pp. 6–7. * ''T. a. acanthion'' is found in
Northern Territory The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an states and territories of Australia, Australian territory in the central and central northern regions of Australia. The Northern Territory ...
and
Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...
. * ''T. a. aculeatus'' is found in
Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...
,
New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...
,
South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
and
Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seychelle ...
. * ''T. a. lawesii'' is found in coastal regions and the highlands of New Guinea, and possibly in the rainforests of Northeast Queensland. * ''T. a. multiaculeatus'' is found on
Kangaroo Island Kangaroo Island, also known as Karta Pintingga (literally 'Island of the Dead' in the language of the Kaurna people), is Australia's third-largest island, after Tasmania and Melville Island. It lies in the state of South Australia, southwest ...
. * '' T. a. setosus'' is found on
Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...
and some islands in
Bass Strait Bass Strait () is a strait separating the island state of Tasmania from the Australian mainland (more specifically the coast of Victoria, with the exception of the land border across Boundary Islet). The strait provides the most direct waterwa ...
. The earliest fossils of the short-beaked echidna date back around 15 million years ago to the
Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
epoch, and the oldest specimens were found in caves in
South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
, often with fossils of the long-beaked echidna from the same period. The ancient short-beaked echidnas are considered to be identical to their contemporary descendants except the ancestors are around 10% smaller.Augee, Gooden and Musser, p. 16. This "post-Pleistocene dwarfing" affects many Australian mammals. Part of the last radiation of monotreme mammals, echidnas are believed to have evolutionally diverged from the platypus around 66 million years ago, between the Cretaceous and Tertiary periods. However, the echidna's pre-Pleistocene heritage has not been traced yet, and the lack of teeth on the fossils found thus far have made it impossible to use dental evidence. The short-beaked echidna was commonly called the spiny anteater in older books, though this term has fallen out of fashion since the echidna bears no relation to the true anteaters. It has a variety of names in the indigenous languages of the regions where it is found. The
Noongar people The Noongar (, also spelt Noongah, Nyungar , Nyoongar, Nyoongah, Nyungah, Nyugah, and Yunga ) are Aboriginal Australian peoples who live in the south-west corner of Western Australia, from Geraldton on the west coast to Esperance on the so ...
from southwestern
Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...
call it the . In
Central Australia Central Australia, also sometimes referred to as the Red Centre, is an inexactly defined region associated with the geographic centre of Australia. In its narrowest sense it describes a region that is limited to the town of Alice Springs and i ...
southwest of
Alice Springs Alice Springs ( aer, Mparntwe) is the third-largest town in the Northern Territory of Australia. Known as Stuart until 31 August 1933, the name Alice Springs was given by surveyor William Whitfield Mills after Alice, Lady Todd (''née'' Al ...
, the
Pitjantjatjara The Pitjantjatjara (; or ) are an Aboriginal people of the Central Australian desert near Uluru. They are closely related to the Yankunytjatjara and Ngaanyatjarra and their languages are, to a large extent, mutually intelligible (all are vari ...
term is or , from the word for spike of porcupine grass ''(
Triodia irritans ''Triodia irritans'' is a species of plant that forms low and dense mounds of tough grassy vegetation. It is found on sandplains in arid regions of southern and central Australia. The species was first described by Robert Brown in 1810. A comm ...
)''. The word can also mean 'slowpoke'. In the
Wiradjuri The Wiradjuri people (; ) are a group of Aboriginal Australian people from central New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , ...
language Language is a structured system of communication. The structure of a language is its grammar and the free components are its vocabulary. Languages are the primary means by which humans communicate, and may be conveyed through a variety of met ...
of Central NSW, it is called ''.'' In central
Cape York Peninsula Cape York Peninsula is a large peninsula located in Far North Queensland, Australia. It is the largest unspoiled wilderness in northern Australia.Mittermeier, R.E. et al. (2002). Wilderness: Earth’s last wild places. Mexico City: Agrupación ...
, it is called in Pakanh, where is a qualifier meaning 'meat' or 'animal', in
Uw Oykangand The Uw Oykangand, otherwise known as the Kwantari, are an Aboriginal Australian people living on the southwestern part of the Cape York Peninsula, in the state of Queensland in Australia. Their neighbours to the northwest are the Yir-Yoront peo ...
and in Uw Olkola, where is a qualifier meaning 'meat' or 'animal'. In the highland regions of southwestern
New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...
, it is known as the in the Daribi and Chimbu languages. The short-beaked echidna is called in the
Motu language Motu (sometimes called Pure Motu or True Motu to distinguish it from Hiri Motu) is a Central Papuan Tip languages, Central Papuan Tip language that is spoken by the Motuan people, Motuans, an indigenous ethnic group of Papua New Guinea. It is com ...
of
Papua New Guinea Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...
.


Description

Short-beaked echidnas are typically in length, with of snout, and weigh between .Egerton, p. 38. However, the Tasmanian subspecies, ''T. a. setosus'', is smaller than its Australian mainland counterparts.Augee, Gooden and Musser, p. 6. Because the neck is not externally visible, the head and body appear to merge. The earholes are on either side of the head, with no external
pinnae The auricle or auricula is the visible part of the ear that is outside the head. It is also called the pinna (Latin for "wing" or " fin", plural pinnae), a term that is used more in zoology. Structure The diagram shows the shape and location ...
. The eyes are small, about in diameter and at the base of the wedge-shaped snout.Augee, Gooden and Musser, p. 55. The nostrils and the mouth are at the distal end of the snout;Augee, Gooden and Musser, p. 2. the mouth cannot open wider than . The body of the short-beaked echidna is, with the exception of the underside, face and legs, covered with cream-coloured spines. The spines, which may be up to long, are modified hairs, mostly made of
keratin Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, ho ...
.Augee, Gooden and Musser, p. 35. Insulation is provided by
fur Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket t ...
between the spines, which ranges in colour from honey to a dark reddish-brown and even black; the underside and short tail are also covered in fur. The echidna's fur may be infested with what is said to be one of the world's largest
fleas Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, ar ...
, '' Bradiopsylla echidnae'', which is about long. The limbs of the short-beaked echidna are adapted for rapid digging; they are short and have strong
claw A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or tarsus ...
s. Their strong and stout limbs allow it to tear apart large logs and move paving stones, and one has been recorded moving a 13.5-kg (30-lb) stone; a scientist also reported that a captive echidna moved a refrigerator around the room in his home.Augee, Gooden and Musser, p. 100. The power of the limbs is based on strong musculature, particularly around the shoulder and torso areas. The
mechanical advantage Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for t ...
of its arm is greater than that of humans, as its biceps connects the shoulder to the forearm at a point further down than for humans, and the chunky
humerus The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
allows more muscle to form.Augee, Gooden and Musser, p. 102. The claws on the hind feet are elongated and curved backward to enable cleaning and grooming between the spines. Like the platypus, the echidna has a low
body temperature Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature ...
—between 30 and 32 °C (86 and 90 °F)—but, unlike the platypus, which shows no evidence of
torpor Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time ...
or hibernation, the body temperature of the echidna may fall as low as 5 °C (41 °F). The echidna does not pant or sweat and normally seeks shelter in hot conditions.Augee, Gooden and Musser, p. 91. Despite their inability to sweat, echidnas still lose water as they exhale. The snout is believed to be crucial in restricting this loss to sustainable levels, through a bony labyrinth that has a refrigerator effect and helps to condense water vapour in the breath.Augee, Gooden and Musser, pp. 114–115. The echidna does not have highly concentrated urine, and around half of the estimated daily water loss of occurs in this manner, while most of the rest is through the skin and respiratory system.Augee, Gooden and Musser, pp. 115. Most of this is replenished by its substantial eating of termites—one laboratory study reported ingestion of around a day, most of which was water. This can be supplemented by drinking water, if available, or licking morning dew from flora.Augee, Gooden and Musser, p. 116. In the Australian autumn and winter, the echidna enters periods of torpor or deep hibernation. Because of its low body temperature, it becomes sluggish in very hot and very cold weather. Like all monotremes, it has one orifice,Augee, Gooden and Musser, p. 3. the cloaca, for the passage of faeces, urine and reproductive products. The male has internal testes, no external scrotum and a highly unusual penis with four knobs on the tip,Augee, Gooden and Musser, p. 79. which is nearly a quarter of his body length when erect. The
gestating Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregnanc ...
female develops a pouch on her underside, where she raises her young.Augee, Gooden and Musser, p. 4. The
musculature Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle ...
of the short-beaked echidna has a number of unusual aspects. The
panniculus carnosus The panniculus carnosus is a part of the subcutaneous tissues in vertebrates. It is a layer of striated muscle deep to the panniculus adiposus.McGrath, J.A.; Eady, R.A.; Pope, F.M. (2004). ''Rook's Textbook of Dermatology'' (Seventh Edition). Black ...
, an enormous muscle just beneath the skin, covers the entire body. By contraction of various parts of the panniculus carnosus, the short-beaked echidna can change shape, the most characteristic shape change being achieved by rolling itself into a ball when threatened, so protecting its belly and presenting a defensive array of sharp spines. It has one of the shortest
spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...
s of any mammal, extending only as far as the
thorax The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the cre ...
. Whereas the human spinal cord ends at the first or second lumbar vertebra, for the echidna it occurs at the seventh thoracic vertebra.Augee, Gooden and Musser, p. 53. The shorter spinal cord is thought to allow flexibility to enable wrapping into a ball. The musculature of the face, jaw and tongue is specialised for feeding. The tongue is the animal's sole means of catching
prey Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...
, and can protrude up to outside the snout. The snout's shape, resembling a double wedge, gives it a significant mechanical advantage in generating a large moment, so makes it efficient for digging to reach prey or to build a shelter. The tongue is sticky because of the presence of
glycoprotein Glycoproteins are proteins which contain oligosaccharide chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycos ...
-rich mucus, which both lubricates movement in and out of the snout and helps to catch ants and termites, which adhere to it. The tongue is protruded by contracting circular muscles that change the shape of the tongue and force it forwards and contracting two genioglossal muscles attached to the caudal end of the tongue and to the
mandible In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...
. The protruded tongue is stiffened by a rapid flow of blood, which allows it to penetrate wood and soil. Retraction requires the contraction of two internal longitudinal muscles, known as the sternoglossi. When the tongue is retracted, the prey is caught on backward-facing
keratin Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, ho ...
ous "teeth", located along the roof of the buccal cavity, allowing the animal both to capture and grind food. The tongue moves with great speed, and has been measured to move in and out of the snout 100 times a minute. This is partly achieved through the elasticity of the tongue and the conversion of
elastic potential energy Elastic energy is the mechanical potential energy stored in the configuration of a material or physical system as it is subjected to elastic deformation by work performed upon it. Elastic energy occurs when objects are impermanently compressed, ...
into
kinetic energy In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its accele ...
. The tongue is very flexible, particularly at the end, allowing it to bend in U-turns and catch insects attempting to flee in their
labyrinthine In Greek mythology, the Labyrinth (, ) was an elaborate, confusing structure designed and built by the legendary artificer Daedalus for King Minos of Crete at Knossos. Its function was to hold the Minotaur, the monster eventually killed by t ...
nests or mounds.Augee, Gooden and Musser, p. 104. The tongue also has an ability to avoid picking up splinters while foraging in logs; the factors behind this ability are unknown.Augee, Gooden and Musser, p. 105. It can eat quickly; a specimen of around can ingest of termites in 10 minutes. The echidna's stomach is quite different from other mammals. It is devoid of secretory glands and has a cornified stratified epithelium, which resembles horny skin.Augee, Gooden and Musser, p. 106. Unlike other mammals, which typically have highly acidic stomachs, the echidna has low levels of acidity, almost neutral, with pH in the 6.2–7.4 range. The stomach is elastic, and gastric peristalsis grinds soil particulates and shredded insects together. Digestion occurs in the small intestine, which is around in length. The insect exoskeletons and soil are not digested, being ejected in the waste. Numerous
physiological adaptations In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the ...
aid the lifestyle of the short-beaked echidna. Because the animal burrows, it must tolerate very high levels of
carbon dioxide Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...
in inspired air, and will voluntarily remain in situations where carbon dioxide concentrations are high. It can dig up to a metre into the ground to retrieve ants or evade predators, and can survive with low oxygen when the area is engulfed by bushfires. The echidna can also dive underwater, which can help it to survive sudden floods. During these situations, the heart rate drops to around 12 beats per minute, around one-fifth of the rate at rest. This process is believed to save oxygen for the heart and brain, which are the most sensitive organs to such a shortage; laboratory testing has revealed the echidna's cardiovascular system is similar to that of the seal. Following the devastation of a bushfire, echidnas can compensate for the lack of food by reducing their daytime body temperature and activity through use of torpor, for a period of up to three weeks. The echidna's optical system is an uncommon hybrid of both mammalian and reptilian characteristics. The cartilaginous layer beneath the sclera of the eyeball is similar to that of reptiles and avians. The small
cornea The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical power ...
l surface is keratinised and hardened, possibly to protect it from chemicals secreted by prey insects or self-impalement when it rolls itself up, which has been observed.Augee, Gooden and Musser, p. 56. The echidna has the flattest lens of any animal, giving it the longest focal length. This similarity to primates and humans allows it to see distant objects clearly.Augee, Gooden and Musser, p. 57. Unlike placental mammals, including humans, the echidna does not have a ciliary muscle to distort the geometry of the lens and thereby change the focal length and allow objects at different distances to be viewed clearly; the whole eye is believed to distort, so the distance between the lens and retina instead changes to allow focusing. The visual ability of an echidna is not great, and it is not known whether it can perceive colour; however, it can distinguish between black and white, and horizontal and vertical stripes. Eyesight is not a crucial factor in the animal's ability to survive, as blind echidnas are able to live healthily. Its ears are sensitive to low-
frequency Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...
sound, which may be ideal for detecting sounds emitted by termites and ants underground. The pinnae are obscured and covered by hair, so predators cannot grab them in an attack, and prey or foreign material cannot enter, although
tick Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by ...
s are known to reside there.Augee, Gooden and Musser, p. 58. The
macula The macula (/ˈmakjʊlə/) or macula lutea is an oval-shaped pigmented area in the center of the retina of the human eye and in other animals. The macula in humans has a diameter of around and is subdivided into the umbo, foveola, foveal av ...
of the ear is very large compared to other animals, and is used as a gravity sensor to orient the echidna. The large size may be important for burrowing downwards.Augee, Gooden and Musser, p. 65. The leathery snout is keratinised and covered in mechano- and thermoreceptors, which provide information about the surrounding environment.Augee, Gooden and Musser, p. 66. These nerves protrude through microscopic holes at the end of the snout,Augee, Gooden and Musser, p. 68. which also has mucus glands on the end that act as electroreceptors. Echidnas can detect
electric field An electric field (sometimes E-field) is the physical field that surrounds electrically charged particles and exerts force on all other charged particles in the field, either attracting or repelling them. It also refers to the physical field fo ...
s of 1.8 mV/cm—1000 times more sensitive than humans—and dig up buried batteries. A series of push rods protrude from the snout. These are columns of flattened, spinous cells, with roughly an average diameter of 50 micrometres and a length of 300 micrometres. The number of push rods per square millimetre of skin is estimated to be 30 to 40. Longitudinal waves are believed to be picked up and transmitted through the rods, acting as mechanical sensors, to allow prey detection. A well-developed
olfactory system The olfactory system, or sense of smell, is the sensory system used for smelling ( olfaction). Olfaction is one of the special senses, that have directly associated specific organs. Most mammals and reptiles have a main olfactory system and an ...
may be used to detect mates and prey. A highly sensitive
optic nerve In neuroanatomy, the optic nerve, also known as the second cranial nerve, cranial nerve II, or simply CN II, is a paired cranial nerve that transmits visual information from the retina to the brain. In humans, the optic nerve is derived fro ...
has been shown to have visual discrimination and spatial memory comparable to those of a rat. The
brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...
and
central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all par ...
have been extensively studied for evolutionary comparison with
placental mammals Placental mammals (infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupialia. Placentalia contains the vast majority of extant mammals, which are partly distinguishe ...
, particularly with its fellow monotreme, the platypus. The average brain volume is 25 ml, similar to a cat of approximately the same size;Augee, Gooden and Musser, p. 45. while the platypus has a largely smooth brain, the echidna has a heavily folded and fissured, gyrencephalic brain similar to humans, which is seen as a sign of a highly neurologically advanced animal.Augee, Gooden and Musser, p. 47. The cerebral cortex is thinner, and the brain cells are larger and more densely packed and organised in the echidna than the platypus, suggesting evolutionary divergence must have occurred long ago. Almost half of the sensory area in the brain is devoted to the snout and tongue, and the part devoted to smell is relatively large compared to other animals. The short-beaked echidna has the largest
prefrontal cortex In mammalian brain anatomy, the prefrontal cortex (PFC) covers the front part of the frontal lobe of the cerebral cortex. The PFC contains the Brodmann areas BA8, BA9, BA10, BA11, BA12, BA13, BA14, BA24, BA25, BA32, BA44, BA45, BA46 ...
relative to body size of any mammal, taking up 50% of the volume in comparison to 29% for humans.Augee, Gooden and Musser, p. 48. This part of the brain in humans is thought to be used for planning and analytical behaviour, leading to debate as to whether the echidna has reasoning and strategising ability. Experiments in a simple maze and with a test on opening a trap door to access food, and the echidna's ability to remember what it has learnt for over a month, has led scientists to conclude its learning ability is similar to that of a cat or a rat. The echidna shows rapid eye movement during sleep, usually around its thermoneutral temperature of 25 °C, and this effect is suppressed at other temperatures. Its brain has been shown to contain a claustrum similar to that of placental mammals, linking this structure to their Common descent, common ancestor.


Ecology and behaviour

No systematic study of the ecology of the short-beaked echidna has been published, but studies of several aspects of their ecological behaviour have been conducted. They live alone, and, apart from the burrow created for rearing young, they have no fixed shelter or nest site. They do not have a home territory they defend against other echidnas, but range over a wide area. The range area has been observed to be between 21 and 93 ha, although one study in Kangaroo Island found the animals there covered an area between 9 and 192 ha. Overall, the mean range areas across the various regions of Australia were 40–60 ha. There was no correlation between sex and range area, but a weak one with size. Echidnas can share home ranges without incident, and sometimes share shelter sites if not enough are available for each animal to have one individually. Short-beaked echidnas are typically active in the daytime, though they are ill-equipped to deal with heat because they have no sweat glands and do not pant. Therefore, in warm weather, they change their patterns of activity, becoming crepuscular or nocturnal. Body temperatures above 34 °C (93 °F) are believed to be fatal, and in addition to avoiding heat, the animal adjusts its circulation to maintain a sustainable temperature by moving blood to and from the skin to increase or lower heat loss. In areas where water is present, they can also swim to keep their body temperatures low. The "thermoneutral zone" for the environment is around 25 °C (77 °F), at which point the metabolism needed to maintain body temperature is minimized. The echidna is endotherm, endothermic, and can maintain body temperatures of around 32 °C.Augee, Gooden and Musser, p. 112. It can also reduce its metabolism and heart rate and body temperature.Augee, Gooden and Musser, p. 107. In addition to brief and light bouts of torpor throughout the year, the echidna enters periods during the Australian winter when it hibernates,Augee, Gooden and Musser, p. 108. both in cold regions and in regions with more temperate climates. During hibernation, the body temperature drops to as low as 4 °C (39 °F). The heart rate falls to four to seven beats per minute—down from 50 to 68 at rest—and the echidna can breathe as infrequently as once every three minutes, 80 to 90% slower than when it is active. Metabolism can drop to one-eighth of the normal rate.Augee, Gooden and Musser, p. 109. Echidnas begin to prepare for hibernation between February and April, when they reduce their consumption and enter brief periods of torpor. Males begin hibernating first, while females that have reproduced start later. During periods of hibernation, the animals average 13 separate bouts of torpor, which are broken up by periods of arousal lasting 1.2 days on average. These interruptions tend to coincide with warmer periods. Males end their hibernation period in mid-June, while reproductive females return to full activity in July and August; nonreproductive females and immature echidnas may not end hibernation until two months later. During euthermia, the body temperature can vary by 4 °C per day. The metabolic rate is around 30% of that of placental mammals, making it the lowest energy-consuming mammal. This figure is similar to that of other animals that eat ants and termites;Augee, Gooden and Musser, p. 113. burrowing animals also tend to have low metabolism generally.Augee, Gooden and Musser, p. 114. Echidnas hibernate even though it is seemingly unnecessary for survival; they begin their hibernation period while the weather is still warm, and food is generally always plentiful.Augee, Gooden and Musser, p. 110. One explanation is that echidnas maximize their foraging productivity by exercising caution with their energy reserves. Another hypothesis is that they are descended from ectothermic ancestors, but have taken to periodic endothermy for reproductive reasons, so that the young can develop more quickly. Supporters of this theory argue that males hibernate earlier than females because they finish their contribution to reproduction first, and they awake earlier to undergo spermatogenesis in preparation for mating, while females and young lag in their annual cycle. During the hibernation period, the animals stay in entirely covered shelter.Augee, Gooden and Musser, p. 111. Short-beaked echidnas can live anywhere with a good supply of food, and regularly feast on ants and termites. They are believed to locate food by smell, using sensors in the tips of their snouts, by shuffling around seemingly arbitrarily, and using their snout in a probing manner. A study of echidnas in New England (New South Wales) has shown that they tend to dig up Scarabaeidae, scarab beetle larvae in spring when the prey are active, but eschew this prey when it is inactive, leading to the conjecture that echidnas detect prey using hearing.Augee, Gooden and Musser, p. 99. Vision is not believed to be significant in hunting, as blind animals have been observed to survive in the wild. Echidnas use their strong claws to pull apart nests and rotting logs to gain access to their prey.Augee, Gooden and Musser, p. 95. They avoid ants and termites that secrete repulsive liquids, and have a preference for the eggs, pupae and winged phases of the insects. Echidnas hunt most vigorously towards the end of the southern winter and early in spring, when their fat reserves have been depleted after hibernation and nursing.Augee, Gooden and Musser, p. 97. At this time, ants have high body fat, and the echidna targets their mounds. The animal also hunts beetles and earthworms, providing they are small enough to fit in a 5-mm gap. The proportion of ants and termites in their diets depends on the availability of prey, and termites make up a larger part in drier areas where they are more plentiful.Augee, Gooden and Musser, p. 98. However, termites are preferred, if available, as their bodies contain a smaller proportion of indigestible exoskeleton. Termites from the Rhinotermitidae family are avoided due to their chemical defences. Scarab beetle larvae are also a large part of the diet when and where available. In the New England study, 37% of the food intake consisted of beetle larvae, although the echidna had to squash the prey in its snout as it ingested it, due to size. Echidnas are powerful diggers, using their clawed front paws to dig out prey and create burrows for shelter. They may rapidly dig themselves into the ground if they cannot find cover when in danger. They bend their belly together to shield the soft, unprotected part, and can also urinate, giving off a pungent liquid, in an attempt to deter attackers. Males also have single small spurs on each rear leg, believed to be a defensive weapon that has since been lost through evolution. Echidnas typically try to avoid confrontation with predators. Instead, they use the colour of their spines, which is similar to the vegetation of the dry Australian environment, to avoid detection. They have good hearing and tend to become stationary if sound is detected. It is likely that echidnas are keystone species in the ecosystem health in Australia, due to their contribution through bioturbation, the reworking of soils through their digging activity. This is based on the estimation that a single echidna will move up to 204 m3 of soil a year, that it is the most widespread of any terrestrial Australian species, is relatively common, and that other bioturbators have been heavily impacted by human settlement. In Australia, they are most common in forested areas with abundant, termite-filled, fallen logs. In agricultural areas, they are most likely to be found in uncleared scrub; they may be found in grassland, arid areas, and in the outer suburbs of the capital cities. Little is known about their distribution in New Guinea. They have been found in southern New Guinea between Merauke in the west and the Kelp Welsh River, east of Port Moresby, in the east, where they may be found in open woodland. Echidnas have the ability to swim, and have been seen cooling off near dams during high temperatures. They have also been seen crossing streams and swimming for brief periods in seas off Kangaroo Island. They swim with only the snout above water, using it as a snorkel.Augee, Gooden and Musser, p. 92.


Reproduction

The solitary short-beaked echidna looks for a mate between May and September; the precise timing of the mating season varies with geographic location.Augee, Gooden and Musser, p. 77. In the months before the mating season, the size of the male's testes increases by a factor of three or more before spermatogenesis occurs.Augee, Gooden and Musser, p. 80. Both males and females give off a strong, musky odour during the mating season, by turning their cloacas inside out and wiping them on the ground, secreting a glossy liquid believed to be an aphrodisiac. During courtship—observed for the first time in 1989—males locate and pursue females. Trains of up to 10 males, often with the youngest and smallest male at the end of the queue, may follow a single female in a courtship ritual that may last for up to four weeks; the duration of the courtship period varies with location. During this time, they forage for food together, and the train often changes composition, as some males leave and other join the pursuit.Augee, Gooden and Musser, p. 78. In cooler parts of their range, such as Tasmania, females may mate within a few hours of arousal from hibernation. Before mating, the male smells the female, paying particular attention to the cloaca. This process can take a few hours, and the female can reject the suitor by rolling herself into a ball. After prodding and sniffing her back, the male is often observed to roll the female onto her side and then assume a similar position himself so the two animals are abdomen to abdomen, having dug a small crater in which to lie. They can lie with heads facing one another, or head to rear.Augee, Gooden and Musser, p. 81. If more than one male is in the vicinity, fighting over the female may occur. Each side of the bilaterally symmetrical, rosette-like, four-headed penis (similar to that of reptiles and in length) is used alternately, with the other half being shut down between ejaculations. Sperm bundles of around 100 each appear to confer increased sperm motility, which may provide the potential for sperm competition between males. This process takes between a half and three hours. Each mating results in the production of a single egg, and females are known to mate only once during the breeding season; each mating is successful. Fertilisation occurs in the oviduct. Gestation takes between 21 and 28 days after copulation, during which time the female constructs a nursery burrow. Following the gestation period, a single, rubbery-skinned egg between in diameter and in weightAugee, Gooden and Musser, p. 84. is laid from her cloaca directly into a small, backward-facing pouch that has developed on her abdomen. The egg is ovoid, leathery, soft, and cream-coloured. Between laying and hatching, some females continue to forage for food, while others dig burrows and rest there until hatching. Ten days after it is laid, the egg hatches within the pouch. The embryo develops an egg tooth during incubation, which it uses to tear open the egg; the tooth disappears soon after hatching.Augee, Gooden and Musser, p. 85. Hatchlings are about long and weigh between . After hatching, young echidnas are known as "puggles". Although newborns are still semitranslucent and still surrounded by the remains of the egg yolk, and the eyes are still barely developed, they already have well-defined front limbs and digits that allow them to climb on their mothers' bodies. Hatchlings attach themselves to their mothers' milk areolae, specialised patches on the skin that secrete milk—monotremes lack nipples—through about 100–150 pores. The puggles were thought to have imbibed the milk by licking the mother's skin, but they are now thought to feed by sucking the areolae. They have been observed ingesting large amounts during each feeding period, and mothers may leave them unattended in the burrow for between five and ten days to find food.Augee, Gooden and Musser, p. 86. Studies of captives have shown they can ingest milk once every two or three days and then increase their mass by 20% in one milk-drinking session lasting between one and two hours. Around 40% of the milk weight is converted into body mass, and as such, a high proportion of milk is converted into growth; a correlation with the growth of the puggle and its mother's size has been observed. By the time the puggle is around , it is left in the burrow while the mother forages for food, and it reaches around after around two months. Juveniles are eventually ejected from the pouch at around two to three months of age, because of the continuing growth in the length of their spines. During this period, the young are left in covered burrows while the mothers forage, and the young are often preyed upon. Suckling gradually decreases until juveniles are weaned at about six months of age. The duration of lactation is about 200 days, and the young leave the burrow after 180 to 205 days, usually in January or February, at which time they weigh around . There is no contact between the mother and young after this point.Augee, Gooden and Musser, p. 88. The composition of the milk secreted by the mother changes over time. At the moment of birth, the solution is dilute and contains 1.25% fat, 7.85% protein, and 2.85% carbohydrates and minerals. Mature milk has much more concentrated nutrients, with 31.0, 12.4 and 2.8% of the aforementioned nutrients, respectively. Near weaning, the protein level continues to increase; this may be due to the need for keratin synthesis for hair and spines, to provide defences against the cold weather and predators. The principal carbohydrate components of the milk are fucosyllactose and saialyllactose; it has a high iron content, which gives it a pink colour.Augee, Gooden and Musser, p. 87. The high iron content and low levels of free lactose differ from eutherian mammals. Lactose production is believed to proceed along the same lines as in the platypus. The age of sexual maturity is uncertain, but may be four to five years. A 12-year field study found the short-beaked echidna reaches sexual maturity between five and 12 years of age, and the frequency of reproduction varies from once every two years to once every six years. In the wild, the short-beaked echidna has an average lifespan of 10 years, though they can live as long as 40. The longest-lived specimen reached 49 years of age in a zoo in Philadelphia.Augee, Gooden and Musser, p. 93. In contrast to other mammals, echidna rates of reproduction and metabolism are lower, and they live longer, as though in slow motion, something caused, at least in part, by their low body temperature, which rarely exceeds 33 °C, even when they are not hibernating. Like its fellow monotreme the platypus, the short-beaked echidna has a system of multiple sex-determination system, sex chromosomes, in which males have four Y chromosomes and five X chromosomes. Males appear to be X1Y1X2Y2X3Y3X4Y4X5
figure
ref name = "Rensetal2007"/>), while females are X1X1X2X2X3X3X4X4X5X5. Weak identity between chromosomes results in meiosis, meiotic pairing that yields only two possible genotypes of sperm, X1X2X3X4X5 or Y1Y2Y3Y4, thus preserving this complex system.


Conservation status

The short-beaked echidna is common throughout most of temperate Australia and lowland New Guinea, and is not listed as endangered. In Australia, it remains widespread across a wide range of conditions, including urban outskirts, coastal forests and dry inland areas, and is especially widespread in Tasmania and on
Kangaroo Island Kangaroo Island, also known as Karta Pintingga (literally 'Island of the Dead' in the language of the Kaurna people), is Australia's third-largest island, after Tasmania and Melville Island. It lies in the state of South Australia, southwest ...
. The most common threats to the animal in Australia are motor vehicles and habitat destruction, which have led to localized extinctions.Augee, Gooden and Musser, p. 120. In Australia, the number of short-beaked echidnas has been less affected by land clearance than have some other species, since they do not require a specialized habitat beyond a good supply of ants and termites. As a result, they can survive in cleared land if the cut-down wood is left in the area, as the logs can be used as shelters and sources of insects. However, areas where the land has been completely cleared for single crops that can be mechanically harvested, such as wheat fields, have seen extinctions. Over a decade-long period, around one-third of echidna deaths reported to wildlife authorities in Victoria were due to motor vehicles, and the majority of wounded animals handed in were traffic accident victims. Studies have shown they often choose to traverse drainage culverts under roads, so this is seen as a viable means of reducing deaths on busy roads in rural areas or national parks where the animals are more common. Despite their spines, they are preyed on by birds of prey, the Tasmanian devil, dingoes, snakes, lizards, goannas, cats, and foxes,Augee, Gooden and Musser, pp. 120–121. although almost all victims are young. Goannas are known for their digging abilities and strong sense of smell, and are believed to have been the main predators of the echidna before the introduction of eutherian mammals. Dingoes are known to kill echidnas by rolling them over onto their backs and attacking their underbellies. A tracking study of a small number of echidnas on Kangaroo Island concluded that goannas and cats were the main predators, although foxes—absent in Kangaroo Island—would be expected to be a major threat. They were eaten by indigenous Australians and the early European settlers of Australia. Hunting and eating of the echidna in New Guinea has increased over time and caused a decline in the population and distribution areas; it is now believed to have disappeared from highland areas. The killing of echidnas was a taboo in traditional culture, but since the tribespeople have become increasingly Westernised, hunting has increased, and the animals have been more easily tracked down due to the use of dogs.Augee, Gooden and Musser, p. 119. Infection with the introduced parasitic tapeworm ''Spirometra erinaceieuropaei'' is considered fatal for the echidna. This waterborne infection is contracted through sharing drinking areas with infected dogs, foxes, cats, and dingos, which do not die from the parasite. The infection is seen as being more dangerous in drier areas, where more animals are sharing fewer bodies of water, increasing the chance of transmission.Augee, Gooden and Musser, p. 121. The Wildlife Preservation Society of Queensland runs an Australia-wide survey, called Echidna Watch, to monitor the species. Echidnas are also known to be affected by other tapeworms, protozoans and herpes-like viral infections, but little is known of how the infections affect the health of the animals or the populations.Augee, Gooden and Musser, p. 122. Although it is considered easy to keep echidnas healthy in captivity, breeding is difficult, partly due to the relatively infrequent cycle. In 2009, Perth Zoo managed to breed some captive short-beaked echidnas, and in 2015 the first zoo-born echidnas were successfully bred there. Until 2006, only five zoos have managed to breed short-beaked echidnas, but no captive-bred young have survived to maturity.Augee, Gooden and Musser, p. 126. Of these five institutions, only one in Australia—Sydney's Taronga Zoo—managed to breed echidnas, in 1977. The other four cases occurred in the Northern Hemisphere, two in the United States and the others in western Europe. In these cases, breeding occurred six months out of phase compared to Australia, after the animals had adapted to Northern Hemisphere seasons. The failure of captive breeding programs has conservation implications for the endangered species of echidna from the genus ''Zaglossus'', and to a lesser extent for the short-beaked echidna.


Cultural references

Short-beaked echidnas feature in the animism, animistic culture of indigenous Australians, including their Australian Aboriginal art, visual arts and stories. The species was a totem for some groups, including the
Noongar people The Noongar (, also spelt Noongah, Nyungar , Nyoongar, Nyoongah, Nyungah, Nyugah, and Yunga ) are Aboriginal Australian peoples who live in the south-west corner of Western Australia, from Geraldton on the west coast to Esperance on the so ...
from Western Australia. Many groups have myths about the animal; one myth explains it was created when a group of hungry young men went hunting at night and stumbled across a wombat. They threw spears at the wombat, but lost sight of it in the darkness. The wombat adapted the spears for its own defence and turned into an echidna. The short-beaked echidna is an iconic animal in contemporary Australia, notably appearing on the Australian five-cent coin, five-cent coin (the smallest denomination), and on a $200 commemorative coin released in 1992. The anthropomorphic echidna ''Millie'' was a mascot for the 2000 Summer Olympics#The Mascots, 2000 Summer Olympics.


See also

* Echidna * Fauna of Australia * List of monotremes and marsupials


Cited references


Works cited

* Augee, M. L., Gooden, B. A. and Musser, A. 2006.
Echidna : extraordinary egg-laying mammal
'. Collingwood, Victoria, CSIRO Publishing * Egerton, L. ed. 2005. ''Encyclopedia of Australian wildlife''. Reader's Digest


General references

* Augee, M. L. and Gooden, B. A. 1993. ''Echidnas of Australia and New Guinea''. Australian National History Press, Sydney * Augee, M. L. 1983. R. Strahan Ed. ''The Australian Museum Complete Book of Australian Mammals''. pp. 8–9. Angus & Robertson * Griffiths, M. 1989
Tachyglossidae
pp. 407–435 in ''Fauna of Australia'' (D. W. Walton and B. J. Richardson, eds.). Mammalia, Canberra, Australian Capital Territory 1B:1–1227.


External links

* *
Tasmanian Department of Water, Primary Industries and Environment – Short-beaked echidna


article with sound clips and images of puggles {{Taxonbar, from=Q193182, from2=Q12902259 Mammals of South Australia Mammals of Tasmania Mammals of Western Australia Mammals of the Northern Territory Mammals of New South Wales Mammals of Queensland Mammals of Victoria (Australia) Mammals of Papua New Guinea Mammals of Western New Guinea Monotremes of New Guinea Myrmecophagous mammals, Myrmecophagous mammals Articles containing video clips Mammals described in 1792 Taxa named by George Shaw