Search results
Results from the WOW.Com Content Network
Peramelemorphia includes the bandicoots and bilbies: it equates approximately to the mainstream of marsupial omnivores. All members of the order are endemic to the twin land masses of Australia - New Guinea and most have the characteristic bandicoot shape: a plump, arch-backed body with a long, delicately tapering snout, very large upright ears ...
The cleavage stages of marsupial development are very variable between groups and aspects of marsupial early development are not yet fully understood. An infant marsupial is known as a joey . Marsupials have a very short gestation period—usually between 12.5 and 33 days, [ 41 ] but as low as 10.7 days in the case of the stripe-faced dunnart ...
The latter subclass is divided into two infraclasses: pouched mammals (metatherians or marsupials), and placental mammals (eutherians, for which see List of placental mammals). Classification updated from Wilson and Reeder's "Mammal Species of the World: A Taxonomic and Geographic Reference" using the "Planet Mammifères" website.
A marsupial has a short gestation period, typically shorter than its estrous cycle, and gives birth to an underdeveloped newborn that then undergoes further development; in many species, this takes place within a pouch-like sac, the marsupium, located in the front of the mother's abdomen.
In mammals, the process is initiated by hormones which cause the muscular walls of the uterus to contract, expelling the fetus at a developmental stage when it is ready to feed and breathe. In some species, the offspring is precocial and can move around almost immediately after birth but in others, it is altricial and completely dependent on ...
instead of a cloaca [a] like monotremes, marsupials and most other vertebrates, the conduits of the urogenital system exit through the vulva or penis and the rectum opens as the anus. [7] The main internal organs and conduits of the placental urogenital system consist of one or two uteri , a single vagina , and a urethra for females, and a ...
The mammals included are only viviparous (marsupials and placentals) as some mammals, which are monotremes (including platypuses and echidnas) lay their eggs. A marsupial has a short gestation period, typically shorter than placental. For more information on how these estimates were ascertained, see Wikipedia's articles on gestational age.
All extant marsupials are endemic to Australasia and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a pouch . Well-known marsupials include kangaroos , wallabies , koalas , opossums , wombats , Tasmanian devils , and the extinct thylacine .