Wynyardiidae is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

of possum-like

marsupials Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia, Wallacea and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a po ...

from the early

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 ...

of Wynyard in

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

, long been considered to display skeletal features that are intermediate between the primitive polyprotodont and the advanced

diprotodont Diprotodontia (, from Greek "two forward teeth") is the largest extant order of marsupials, with about 155 species, including the kangaroos, wallabies, possums, koala, wombats, and many others. Extinct diprotodonts include the hippopotamus-sized ...

marsupials. ''Wynyardias

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 ...

is clearly phalangeroid in external

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...

, resembling closely that of the

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

phalangerid ''

Trichosurus vulpecula The common brushtail possum (''Trichosurus vulpecula'', from the Greek for "furry tailed" and the Latin for "little fox", previously in the genus ''Phalangista'') is a nocturnal, semiarboreal marsupial of the family Phalangeridae, native to Austr ...

''. This indicates that by 21 million years ago, an

unambiguous Ambiguity is the type of meaning in which a phrase, statement or resolution is not explicitly defined, making several interpretations plausible. A common aspect of ambiguity is uncertainty. It is thus an attribute of any idea or statement ...

ly phalangerid brain had evolved within the Diprotodonta family, indicating that both groups had a common ancestor prior to this date. Research on ''Wynyardia bassianas relationship with

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

phalangerid

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 ...

of the Miocene is an ongoing process.

Species

* †Wynyardiidae (Osgood 1921) ** †''Wynyardia bassiana'' (Spencer 1901) ** †'' Muramura williamsi'' (Pledge in Archer 1987) ** †'' Muramura pinpensis'' (Pledge N S 2003) ** †'' Namilamadeta snideri'' (Rich & Archer 1979)

Notes

References

* Wildlife of Gondwana, By Patricia Vickers-Rich and Thomas Hewett Rich 1993 Reed.

External links

Partial skeleton

By Neville S. Pledge 2003, A New Species of Muranura
Pleistocene mammals of Australia Prehistoric vombatiforms Oligocene first appearances Miocene extinctions Prehistoric mammal families {{paleo-marsupial-stub