Marsupials are mammals in which the female typically has a pouch in which it rears its young through early infancy.

They differ from placental mammals (Placentalia) in their reproductive traits.

The early birth of marsupials removes the developing young much sooner than in placental mammals, and marsupials have not needed to develop a complex placenta to protect the young from its mother's immune system.

Early birth places the tiny newborn marsupial at greater risk, but significantly reduces the risks associated with pregnancy, as there is no need to carry a large fetus to full-term in bad seasons.

There are about 334 species of marsupials, over 200 of them native to Australia and nearby islands to the north..

For more information about the topic Marsupial, read the full article at Wikipedia.org, or see the following related articles:

Mammal — The mammals are the class of vertebrate animals characterized by the production of milk in females for the nourishment of young, from mammary glands ...  > read more

Placenta — The placenta is an ephemeral (temporary) organ present only in female placental vertebrates during gestation (pregnancy). All mammals other than ...  > read more

Koala — The Koala (Phascolarctos cinereus) is a thickset arboreal marsupial herbivore native to Australia, and the only extant representative of the family, ...  > read more

Sugar Glider — The Sugar Glider (Petaurus breviceps), sometimes called the Flying Sugar, is a small gliding possum native to eastern and northern mainland ...  > read more

Related Stories

Evolution Of An Imprinted Domain In Mammals (June 3, 2008) — A new PLoS Biology article investigates the evolution of genomic imprinting in a specific region of the mammalian genome. The work shows that different regions became imprinted at different times ...  > read more

Loss Of Egg Yolk Genes In Mammals And The Origin Of Lactation And Placentation (March 19, 2008) — The major egg yolk genes, those that express vitellogenins, appear to have progressively lost their functionality during mammalian evolution, probably due to the emergence of the mammalian-specific ...  > read more

Researchers Discover The Earliest Known Relative Of Marsupial Mammals (December 12, 2003) — An International team, including scientists from Carnegie Museum of Natural History, have discovered the most primitive and oldest know relative of all marsupial ...  > read more

Primitive Mouse-Like Creature May Be Ancestral Mother Of Australia's Unusual Pouched Mammals (March 26, 2008) — A new study has confirmed that a primitive mouse-like creature that lived 55 million years ago (called Djarthia) is also a primitive relative of the small marsupial known as the Monito del Monte -- ...  > read more

Rare Example Of Darwinism Seen In Action (August 1, 2007) — A research team has found experimental evidence that supports a controversial theory of genetic conflict in the reproduction of those animals that support their developing offspring through a ...  > read more

Search ScienceDaily

New Asteroids Discovered