Re: [dinosaur] Why birds are living dinosaurs

[Ronald Orenstein <ron.orenstein@rogers.com>]

I take your point, but (and perhaps it's just me) I haven't seen much use of what I would imagine are equivalent terms ('non-mammalian synapsid', for example, or for that matter 'non-tetrapod sarcopterygian').

Ronald Orenstein
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On Monday, April 12, 2021, 04:06:30 p.m. EDT, Thomas Richard Holtz <tholtz@umd.edu> wrote:

Dawid Marzurek writes:

I see two problems here (excluding the general confusion of lay persons):

1) paraphylethic groups are actually useful. The presence of a "non-avian dinosaur" term is an evidence;

2) professionals refer to K-Pg event as an extinction of dinosaurs.

------

Sloppy thinking and dialog, even on the part of professionals, doesn't make it right or reasonable.

Indeed, as decades of work shows, it leads to incorrect conclusions. Hence people who are convinced that "reptiles" have three-chambered hearts and lack parental care, and then assume crocodiles and dinosaurs were the same. Or that "fish" all have the same metabolism or life history strategy. And just because some professional biologists say these things, too (which they do!!) doesn't mean that is okay.

The use of "non-avian dinosaur" is useful in BEING ponderous and unwieldy: it shows the artificiality of the concept.

On Mon, Apr 12, 2021 at 3:49 PM dawidmazurek@wp.pl <dawidmazurek@wp.pl> wrote:

I see two problems here (excluding the general confusion of lay persons):

1) paraphylethic groups are actually useful. The presence of a "non-avian dinosaur" term is an evidence;

2) professionals refer to K-Pg event as an extinction of dinosaurs.

--

Thomas R. Holtz, Jr.
Email: tholtz@umd.edu         Phone: 301-405-4084
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