Hi, Kaichos Man.
Kaichos Man writes:
What's to say Cynodonts weren't mammals? As far as I can tell from the research (correct me if I'm wrong) we can't even prove they laid eggs. They had a couple of extra bones in their jaw. Does that mean they weren't mammals?
Since the term "mammal" uses the jawbone character in its definition, cynodonts are not mammals. But, it's just an arbitrary term used to represent evolutionary relationships. Cynodonts certainly were less related to everything that we call "mammals" than those mammals are to each other. That's all that matters when talking about evolution.
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Kaichos Man writes:
For example, can a mammal be egg-laying? Can a mammal be poisonous?
The Platypus is both.
Minor correction: the platypus is
venomous, not poisonous. Poison is a defensive/passive secretion that works via ingestion. Venom is an offensive/active weapon that is injected into the bloodstream.
Sorry. Pet peeve.
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Kaichos Man writes:
If Cynodontia were mammals, all arguments about their evolution of lactation become moot.
Correction: if the Cynodontia were
derived mammals, all arguments about their evolution of lactation become moot. But, since, even if they were mammals, they would be the earliest mammals known; they still would represent an earlier stage in mammal evolution than everything else that is a mammal, so they would still be the ideal clade in which to study the evolution of mammary secretions.
Edited by Bluejay, : No reason given.
-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.