| #2 (permalink) Thu Jun 03, 2010 9:26 am What do you mean by mammals?
I'm not going to answer the question 'what is a mammal?' as it is obvious from your next comment that you already know what a mammal is and what characteristics they have.
A platypus is a mammal, it is semi-aquatic and belongs to the sub group of mammals called 'monotremes', the only mammals that lay eggs instead of giving birth to live young. Only platypuses and echidnas fall into this group.
The name Monotreme comes from the fact that the echidnas and the platypus use the same opening for reproduction and eliminating waste products, which is an attribute that is found in reptiles (Encyclopaedia Britannica, 1995). Other reptilian characteristics include the ability to lay eggs, cervical ribs, and that there is "localisation of ascorbic acid synthesis in the kidney (Serena, 1994; p.118).
I hope this clarifies things. I certainly learned something from researching the answer. This particular test appears to require a knowledge of more than just the indicated vocabulary!
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Joined: 08 Apr 2010
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