[Baron Munchausen]

Originally posted by Loser:
The platypus sits well as a mammal, as it has mammaries. It's not a 'placental' mammal, it is instead a 'monotreme', and is only one of three known species of monotremes.

hmm... shouldn't talk science without a spellcheck, but I will anyway.

I thought it was only two known species of monotremes? The platypus and the echidna are the only known survivors of this primitive class of mammals. Are there multiple species of either? I thought each was unique? Barring some 'great discovery' in a hidden pocket of Australian wilderness, all other monotremes are apparently extinct.

And the platypus does not have mammaries, which is one of the characteristics that makes it a monotreme. It simply 'sweats' milk out on its belly and the baby laps it up. The distinct mammary gland comes later with 'true' mammals.