"No....they are different 'kinds' within the same main specie."
"Animals are animals, but there are many different kinds."
is that kind, or 'kind'? If it's the former, duh. If it's the latter, see above.
"Just because 2 kinds can't breed doesn't make them different main species."
'main' species? WTF?
"A cat and a dog are both the same main specie...animal...but they can't breed."
wait... 'animal' is a 'main species'? So... by 'main species', you actually mean 'kingdom'?
"One main specie can never morph into another main specie !....absolutely impossible !"
Hmmm. Well, for the most part, that's true. Plants will never 'morph' into animals. We're agreed on that. However, animals and plants evolved from a common ancestor... oh, hell, why am I even bothering to explain it? The people who read FSTDT probably already know, and in the unlikely event Theme_investor reads my explanation, s/he wouldn't get it, anyhow.
ETA: Hadanelith, according to google, it refers to any coinage made of precious metal.