Monotremes (monos, single + trema, hole; refers to the cloaca) are mammals that lay eggs instead of giving birth to live young like marsupials (Metatheria) and placental mammals (Eutheria). The subclass comprises a single order, Monotremata (though sometimes the subclass Prototheria is used).

General characteristics

---

Like other mammals, monotremes are warm-blooded with a high metabolic rate (though not as high as other mammals, see below); have hair on their bodies; produce milk to feed their young; have a single bone in their lower jaw; and have three middle ear bones (though this feature is now thought to have evolved independently in monotremes, see below).

Monotremes were very poorly understood for many years, and to this day some of the 19th century myths that grew up around them endure. It is still sometimes thought, for example, that the monotremes are "inferior" or quasi-reptilian, and that they are a distant ancestor of the "superior" placental mammals. It now seems plain that modern monotremes are the survivors of an early branching of the mammal tree; a later branching is thought to have led to the marsupial and placental groups.

More on [ Monotreme ]

Monotremata - Twitter Search

all species of echidna! http://www.mammalsrus.com/prototheria/monotremata/tachyglossidae/tachyglossidae.html
mammalsrus (ateeq ahmad) Thu, 05 Nov 2009 01:31:10 -0000
all species of echidna! http://www.mammalsrus.com/prototheria/monotremata/tachyglossidae/tachyglossidae.html
egg-laying mammals! http://www.mammalsrus.com/prototheria/monotremata/monotremata.html
mammalsrus (ateeq ahmad) Thu, 05 Nov 2009 01:30:37 -0000
egg-laying mammals! http://www.mammalsrus.com/prototheria/monotremata/monotremata.html

Subscribe to Monotremata RSS feed