Re: Triassic mammal-like reptiles?

["T. Michael Keesey" <keesey@gmail.com>]

On 11/8/05, Phil Bigelow <bigelowp@juno.com> wrote:
>
> Very loosely, "protomammal" implies anagenesis, which most certainly
> didn't occur in the earliest synapsids.  They were a bushy tree of
> critters, most of which ended up as dead-end lineages.  The use of the
> word "protomammal" only perpetuates the mistaken lay belief that any
> randomly chosen "protomammal" can be considered a direct ancestor of
> mammals.  Dimetrodon isn't a "protomammal" any more than a platypus is a
> "protomarsupial".

Eh, good points.

> Referring to Dimetrodon as a "mammal relative" is accurate and it is
> correct.  But even dinosaurs are "mammal relatives", so perhaps the term
> should be amended to "mammals' closest relatives".

Everything is related to everything, but I think it's clear enough in
context. "Mammal relative", in the context of talking about
prehistoric life to laypeople, suggests something that is more related
to mammals than to other extant organisms--which is precisely what
non-mammalian synapsids are.

I mean, nobody, lay or otherwise, looks at a skink and blurts out,
"Hey, a mammal relative!"
--
Mike Keesey
The Dinosauricon: http://dino.lm.com
Parry & Carney: http://parryandcarney.com