"staining. The beetles and larvae continue their tunnelling activities in stacked timber, and although at first they only burrow through the sapwood, later they move on to the heartwood. Insecticides have no effect on adults and larvae inside their tunnels, but kiln drying of the timber can kill them when the fungus is unable to survive the dessication. Platypus cylindrus Platypus cylindrus, commonly known as the oak pinhole borer, is a species of ambrosia beetle in the weevil family Curculionidae. The adults and larvae burrow under the bark of mature oak trees. It is native to Europe. The adult oak"
"known living species of monotreme occur in Australia: the platypus and the short-beaked echidna. The platypus — a venomous, egg-laying, duck-billed, amphibious mammal — is one of the strangest creatures in the animal kingdom. When a platypus pelt was first presented by Joseph Banks to English naturalists in the late 18th century, they were convinced it must be a cleverly created hoax. Another strange monotreme is the short-beaked echidna; covered in hairy spikes, with a tubular snout in the place of a mouth, it has a tongue that can move in and out of the snout about 100 times per"
"to these ancient forms and that at least ""Teinolophos"" was a rather different mammal lacking several speciations seen in platypi. However, the last common ancestor between platypi and echidnas probably was aquatic, and echidnas thus secondarily became terrestrial. ""Monotrematum sudamericanum"" is currently the oldest aquatic monotreme known. It has been found in Argentina, indicating monotremes were present in the supercontinent of Gondwana when the continents of South America and Australia were joined via Antarctica, or that monotremes existed along the shorelines of Antarctica in the early Cenozoic. Marine mammals are aquatic mammals that rely on the ocean for their existence."
"New Guinea, and Kangaroo Island while the long-beaked echidna (""Zaglossus bruijni"") lives only in New Guinea. The platypus lives in the waters of eastern Australia. They have been introduced to Tasmania, King Island, and Kangaroo Island. These Monotremes are totally absent in the rest of the world. On the other hand, Australia is missing many groups of placental mammals that are common on other continents (carnivorans, artiodactyls, shrews, squirrels, lagomorphs), although it does have indigenous bats and murine rodents; many other placentals, such as rabbits and foxes, have been introduced there by humans. Other animal distribution examples include bears, located"
"Monotrematum Monotrematum is an extinct monotreme genus from the Paleocene (Peligran) Salamanca Formation in Patagonia, Argentina. ""M. sudamericanum"" is known only from two lower and one upper platypus teeth. It is the only known non-Australasian ornithorhynchid. The main difference, apart from continent and age, is its size: the teeth of ""Monotrematum"" are around twice as large as other similar species. These fossils presently reside in the collections of Museo de La Plata and Museo Paleontológico Egidio Feruglio, both in Argentina. According to Pascual, ""The preserved enamel in the central region shows that the crown pattern is almost identical to that"
"mammals (group that includes marsupials and placentals, see below). ""Teinolophos"", from Australia, is the earliest known monotreme. A 2007 study (published 2008) suggests that it was not a basal (primitive, ancestral) monotreme but a full-fledged platypus, and therefore that the platypus and echidna lineages diverged considerably earlier. A more recent study (2009), however, has suggested that, while ""Teinolophos"" was a type of platypus, it was also a basal monotreme and predated the radiation of modern monotremes. The semi-aquatic lifestyle of platypuses prevented them from being outcompeted by the marsupials that migrated to Australia millions of years ago, since joeys need"
"some migrated across Antarctica to South America, both of which were still united with Australia at that time.; however, several genetic studies suggest an origin in the Triassic. Excepting ""Ornithorhynchus anatinus"", all the animals listed in this section are known only from fossils. Monotreme Monotremes (from Greek μονός, ""monos"" (""single"") and τρῆμα, ""trema"" (""hole""), referring to the cloaca) are one of the three main groups of living mammals, along with placentals (Eutheria) and marsupials (Metatheria). The monotremes are typified by laying eggs rather than bearing live young, but like marsupials store their newly hatched larvae-like developing newborn puggles in a"
"was a taxidermied mount was challenged by Robert Paddle in 2008. Paddle believed that the thylacine was a living specimen from Hobart's Beaumaris Zoo. Henry Burrell Henry (Harry) James Burrell OBE (19 January 1873 – 29 July 1945) was an Australian naturalist who specialised in the study of monotremes. He was the first person to successfully keep the platypus in captivity and was a lifelong collector of specimens and contributor of journal articles on monotremes. Henry James Burrell was born at Rushcutters Bay, Sydney, the fourth son of Douglas and Sarah Rose Burrell (née Stacey). He had some schooling but"
"Monotreme Monotremes (from Greek μονός, ""monos"" (""single"") and τρῆμα, ""trema"" (""hole""), referring to the cloaca) are one of the three main groups of living mammals, along with placentals (Eutheria) and marsupials (Metatheria). The monotremes are typified by laying eggs rather than bearing live young, but like marsupials store their newly hatched larvae-like developing newborn puggles in a pouch, and by structural differences in their brains, jaws, digestive and reproductive tracts, and other body parts compared to the more common mammalian types. However, like all mammals, the female monotremes nurse their young with milk. Monotremes are traditionally referred to as the"
"to remain attached to their mothers and would drown if their mothers ventured into water (though there are exceptions like the water opossum and the lutrine opossum; however, they both live in South America and thus don't come into contact with monotremes). Genetic evidence has determined that echidnas diverged from the platypus lineage as recently as 19-48M, when they made their transition from semi-aquatic to terrestrial lifestyle. Monotremes have some features that may be inherited from the cynodont ancestors: Unlike other mammals, female monotremes do not have nipples and feed their young by ""sweating"" milk from patches on their bellies."
"bones. In common with reptiles and marsupials, monotremes lack the connective structure (corpus callosum) which in placental mammals is the primary communication route between the right and left brain hemispheres. The anterior commissure does provide an alternate communication route between the two hemispheres, though, and in monotremes and marsupials it carries all the commissural fibers arising from the neocortex, whereas in placental mammals the anterior commissure carries only some of these fibers. Extant monotremes lack teeth as adults. Fossil forms and modern platypus young have a ""tribosphenic"" form of molars (with the occlusal surface formed by three cusps arranged in"
"the first fishes, amphibians, and reptiles – are the only vertebrates to possess the evolutionarily recent, outermost part of the cerebral cortex known as the neocortex. The neocortex of monotremes (the duck-billed platypus and several species of spiny anteaters) and of marsupials (such as kangaroos, koalas, opossums, wombats, and Tasmanian devils) lack the convolutions – gyri and sulci – found in the neocortex of most placental mammals (eutherians). Within placental mammals, the size and complexity of the neocortex increased over time. The area of the neocortex of mice is only about 1/100 that of monkeys, and that of monkeys is"
"of ""Obdurodon"": it is composed of two V-shaped lobes, the anterior of which is wider, separated from the posterior one by a valley that connects the lingual and buccal sides of the crown separating the anterior and posterior lobes."" Monotrematum Monotrematum is an extinct monotreme genus from the Paleocene (Peligran) Salamanca Formation in Patagonia, Argentina. ""M. sudamericanum"" is known only from two lower and one upper platypus teeth. It is the only known non-Australasian ornithorhynchid. The main difference, apart from continent and age, is its size: the teeth of ""Monotrematum"" are around twice as large as other similar species. These"
"for egg shell formation) is shared with birds; the presence of this symplesiomorphy suggests that the common ancestor of monotremes, marsupials, and placental mammals was oviparous, and that this trait was retained in monotremes but lost in all other extant mammal groups. DNA analyses suggest that although this trait is shared and is synapomorphic with birds, platypuses are still mammals and that the common ancestor of extant mammals lactated. L-ascorbic acid is synthesized only in the kidneys. The monotremes also have extra bones in the shoulder girdle, including an interclavicle and coracoid, which are not found in other mammals. Monotremes"
"and a great many unique plants and animals, some of them common to the entire area, others specific to particular parts but sharing a common ancestry. The long isolation of Australasia from other continents allowed it to evolve relatively independently, which makes it home to many unique families of plants and animals. Australia and New Guinea are distinguished by their marsupial mammals, including kangaroos, possums, and wombats. The last remaining monotreme mammals, the echidnas and the platypus, are endemic to Australasia. Prior to the arrival of humans about 50,000 years ago, only about one-third of Australasian mammal species were placental."
"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 ""Monotrematum"", ""Obdurodon"", and ""Ornithorhynchus"": Another two genera, ""Steropodon"" and ""Teinolophos"", were originally thought to belong to the Ornithorhynchidae. However, they were both placed into a new family, the Steropodontidae. This decision was made based on differences in the dentary recovered from the Griman Creek Formation, Lightning Ridge, New South Wales, Australia. This dentary is the holotype for the genus ""Steropodon"", thus the lack of"
"Henry Burrell Henry (Harry) James Burrell OBE (19 January 1873 – 29 July 1945) was an Australian naturalist who specialised in the study of monotremes. He was the first person to successfully keep the platypus in captivity and was a lifelong collector of specimens and contributor of journal articles on monotremes. Henry James Burrell was born at Rushcutters Bay, Sydney, the fourth son of Douglas and Sarah Rose Burrell (née Stacey). He had some schooling but had an itinerant lifestyle during which he spent some years as a vaudeville comedian. In 1901 he married Susan Emily Naegueli, a 42-year-old divorcee,"
"Obdurodon Obdurodon is an extinct monotreme genus containing three species. It is sometimes referred as the Riversleigh platypus, after the location of its discovery at Riversleigh. Individuals of ""Obdurodon"" differed from modern platypuses in that adult individuals retained their molar teeth (in the modern platypus, individuals lose all of their teeth upon reaching adulthood). Compared to the modern platypus, which is a mostly benthic forager, ""Obdurodon"" foraged pelagically. ""Obdurodon dicksoni"" was described in 1992 by Michael Archer, F. A. Jenkins, S. J. Hand, P. Murray, and H. Godthelp on the basis of QM F20564, a skull and several scattered teeth"
"snout and some of their spines, and are known to journey to water in order to groom and bathe themselves. Echidnas and the platypus are the only egg-laying mammals, known as monotremes. The average lifespan of an echidna in the wild is estimated around 14–16 years. When fully grown, a female can weigh up to and a male can weigh up to . The echidnas' sex can be inferred from their size, as males are 25% larger than females on average. The reproductive organs also differ, but both sexes have a single opening called a cloaca, which they use to"
"can strike any animal that tries to get close with its sharp claws. Silky anteater The silky anteater (Cyclopes didactylus), also known as the pygmy anteater, is a species of anteater in the genus ""Cyclopes"", the only living genus in the family Cyclopedidae. It is found in southern Mexico, and Central and South America. A taxonomic review in 2017, including both molecular and morphological evidence, found that ""Cyclopes"" may comprise not one species (""C. didactylus""), as previously thought, but at least seven. The only known extinct cyclopedid species, ""Palaeomyrmidon incomtus"", from the Late Miocene (c. 7 to 9 million years"
"has nine sex chromosomes—5 Xs and 4 Ys, and the male platypus has 5 Xs and 5 Ys. Platypuses are a monotreme species whose mechanism of sex determination has been extensively studied. There is some contention in academia about the evolutionary origin and the proper taxonomy of platypuses. A recent study revealed that four platypus X chromosomes, as well as a Y chromosome, are homologous to some regions on the avian Z chromosome. Specifically, platypus X1 shares homology with the chicken Z chromosome, and both share homology with the human chromosome 9. This homology is important when considering the mechanism"
"information led to the original misclassification. Further research on ""Teinolophos"" has indeed shown it to be an animal much different from ornithochrynchids, lacking a beak, possessing a more complete mammalian dentition, and retaining primitive ears connected to the jaw as in more basal mammals. The extinct ""Ornithorhynchus maximus"" was once included in ""Ornithorhynchus"", but has now been determined to be from the echidna family as ""Zaglossus robustus"". 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"
"which is called an infant in humans, should typically begin respiration on its own shortly after birth. Not long after, the placenta is passed as well. Most mammals eat this, as it is a good source of protein and other vital nutrients needed for caring for the young. Monotremes, only five species of which exist, all from Australia and New Guinea, are mammals that lay eggs. They have one opening for excretion and reproduction called the cloaca. They hold the eggs internally for several weeks, providing nutrients, and then lay them and cover them like birds. Like marsupial ""joeys"", monotreme"
"platypus venom emerged before the divergence of platypus and echidnas, suggesting that the most recent common ancestor of these taxa was also possibly a venomous monotreme. Monotremes are conventionally treated as comprising a single order Monotremata, though a recent classification proposes to divide them into the orders Platypoda (the platypus along with its fossil relatives) and Tachyglossa (the echidnas, or spiny anteaters). The entire grouping is also traditionally placed into a subclass Prototheria, which was extended to include several fossil orders, but these are no longer seen as constituting a group allied to monotreme ancestry. A controversial hypothesis now relates"
"Prototheria Prototheria (; from Greek πρώτος, ""prōtos"", first, + θήρ, ""thēr"", wild animal) is the subclass to which the order Monotremata belongs. Most of the animals in this group are extinct. The egg-laying monotremes are known from fossils of the Cretaceous and Cenozoic periods; they are represented today by the platypus and several species of echidna. The names Prototheria, Metatheria, and Eutheria (meaning ""first beasts"", ""changed beasts"", and ""true beasts"", respectively) refer to the three mammalian groupings of which we have living representatives. Each of the three may be defined as a total clade containing a living crown-group (respectively the"
"retain a reptile-like gait, with legs on the sides of, rather than underneath, their bodies. The monotreme leg bears a spur in the ankle region; the spur is not functional in echidnas, but contains a powerful venom in the male platypus. This venom is derived from b-defensins, proteins that are present in mammals that create holes in viral and bacterial pathogens. Some reptile venom is also composed of different types of b-defensins, another trait shared with reptiles. It is thought to be an ancient mammalian characteristic, as many non-monotreme archaic mammal groups also possess venomous spurs. The key anatomical difference"
"central spine on the pleotelson, and the shape and structure of the uropods and pereopods. Giant isopods have been recorded in the West Atlantic from off Georgia (USA) to Brazil, including the Gulf of Mexico and the Caribbean. The four known Atlantic species are ""B. obtusus"", ""B. miyarei"", ""B. maxeyorum"" and ""B. giganteus"", and the last of these is the only species recorded off the United States. The remaining ""Bathynomus"" species are all restricted to the Indo-Pacific. No species occurs in both the Atlantic and Indo-Pacific; previous records of ""B. giganteus"" from the Indo-Pacific are now considered misidentifications of other"
"and the manatee, which have only six. Three-toed sloth The three-toed sloths are tree-living mammals from South and Central America. They are the only members of the genus Bradypus and the family Bradypodidae. The four living species of three-toed sloths are the brown-throated sloth, the maned sloth, the pale-throated sloth, and the pygmy three-toed sloth. A study of mitochondrial cytochrome b and 16S rRNA sequences suggests that ""B. torquatus"" diverged from ""B. variegatus"" and ""B. tridactylus"" about 12 million years ago, while the latter two split 5 to 6 million years ago. The diversification of ""B. variegatus"" lineages was estimated"
"too, is now claimed to have evolved independently in monotremes and therians, although, as with the analogous evolution of the tribosphenic molar, this hypothesis is disputed. Nonetheless, findings on the extinct species ""Teinolophos"" confirm that suspended ear bones evolved independently among monotremes and therians. The external opening of the ear still lies at the base of the jaw. The sequencing of the platypus genome has also provided insight into the evolution of a number of monotreme traits, such as venom and electroreception, as well as showing some new unique features, such as the fact that monotremes possess 10 sex chromosomes"
"teeth. In addition, the group seems not to have been as diverse in their evolutionary history, in comparison to members of both Metatheria and Eutheria. Future analysis and better fossil remains could affect the membership of Yinotheria as well as rearranging and revising the relationships of stem-monotremes and crowned monotremes. Below is a simplified tree on Averianov ""et. al"", 2014 after Woodburn, 2003 and Ashwell, 2013 Yinotheria Yinotheria is a proposed basal mammalian subclass clade that contains a few fossils of the Mesozoic and the extant monotremes. Today, there are only five surviving species, which live in Australia and New"
"of concept"" for the use of cryostorage as a genome bank for threatened amphibians and also other animals. Gastric-brooding frog The gastric-brooding frogs or platypus frogs (""Rheobatrachus"") were a genus of ground-dwelling frogs native to Queensland in eastern Australia. The genus consisted of only two species, both of which became extinct in the mid-1980s. The genus was unique because it contained the only two known frog species that incubated the prejuvenile stages of their offspring in the stomach of the mother. The combined ranges of the gastric-brooding frogs comprised less than . Both species were associated with creek systems in"
"for example, but about 310 in 2007, with an increase in quality such that ""at least 18 Mesozoic mammals are represented by nearly complete skeletons"". Some writers restrict the term ""mammal"" to the crown group mammals, the group consisting of the most recent common ancestor of the monotremes, marsupials, and placentals, together with all the descendants of that ancestor. In an influential 1988 paper, Timothy Rowe advocated this restriction, arguing that ""ancestry... provides the only means of properly defining taxa"" and, in particular, that the divergence of the monotremes from the animals more closely related to marsupials and placentals ""is"
"primarily in compensated areas of the Z chromosome—areas that are differentially expressed in male and female chickens. Thus it is likely that these CpG islands are locations where genes on the male Z chromosome are methylated and silenced, but which stay functional on the female Z chromosome. Monotremes are a class of basal mammals that also lay eggs. They are an order of mammals that includes platypuses and four species of echidna, all of which are egg-laying mammals. While monotremes use an XX/XY system, unlike other mammals, monotremes have more than two sex chromosomes. The male short-beaked echidna, for example,"