T. Michael Keesey writes:
It's not that scientists are redefining terms like "planet" and
"dinosaur"; it's that they were never rigorously defined in the first
place. Rigorous definitions are going to include and/or exclude some
traditional content. But it's okay, because that traditional content
never delimited a scientifically useful group to begin with. The
traditional usages are just accidents of history, and it's high time
to move on.
Hmm. I think that now it _is_ time to move on and accept that
Dinosauria includes birds. But we may as well be honest with
ourselves and admit that the scientists who made it so screwed up.
Everyone knew what "dinosaur" meant. It would have been better to
discard the taxon Dinosauria when it became apparent that it was
paraphyletic, define a new name for the clade (_Iguanodon_ +
_Megalosaurus_) and let everyone keep on using the well-established
vernacular term to mean what it always meant.
But I realise that ship has sailed. Same with Reptilia.
_/|_
___________________________________________________________________
/o ) \/ Mike Taylor <mike@miketaylor.org.uk> http://
www.miketaylor.org.uk
)_v__/\ "Never write $$a[$i] when you mean ${$a[$i]} or @$a[$i] when
you mean @{$a[$i]}. Those won't work at all" -- the Perl Data
Structures Cookbook.