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Date: Mon, 14 Mar 2005 11:32:50 +0100
From: [unknown]
To: PML <phylocode@ouvaxa.cats.ohiou.edu>
Subject: Fw: PhyloCode
Sorry, the original went to another mailing list... here's it again..= . ----- Original Message ----- =46rom: "David Marjanovic" <david.marjanovic@gmx.at> To: "DML" <dinosaur@usc.edu> Sent: Monday, March 14, 2005 10:43 AM Subject: Re: PhyloCode >> Ok my rule can be dropped in such cases such as in this case in wh= ich=20 >> note >> must be taken that if you tell people they have eaten dinosaur or = reptile >> when they eat bird they will take it that you lied to them as the = usage >> was not meant for that context. > > As the president (Kevin de Queiroz) said: The word "bird" will not > disappear. The word "Aves" will not disappear either. Under current > classifications, you can already tell people they have eaten verteb= rate=20 > for > dinner without being wrong -- and this doesn't any damage to "bird"= or > "Aves". > >> All well and fine but for other cases my principle should be appli= ed. No >> word can even in theory be strictly speaking defined 100% because = you >> can't as Quantum Mechanics teaches give a perfect measurement >> to anything without the act of measurement altering what is being >> measured. What's a measurement hasn't even been defined >> according to everyone. We can define things even >> without knowing much at all about it. What is a human being? > > Here in biological nomenclature, we don't care at all what a human = being=20 > is. > We're not trying to measure. Nomenclature (unlike phylogenetics!!!)= =20 > consists > _purely_ of _arbitrary definitions_. Just like mathematics. "1 + 1 = =3D 2" is > absolutely true _because and only because_ of the ways "1", "+", "= =3D" and=20 > "2" > are _defined_. In the same way, it is an absolute truth* that Dinos= auria > consists of "the most recent common ancestor of *Megalosaurus buckl= andii* > and *Iguanodon bernissartensis*, and all its descendants". Why? Sim= ply > because we say so and call that a definition. > > Now what a dinosaur is, which organisms are and are not descendants= of=20 > that > common ancestor, or what that (currently unknown) "most recent comm= on > ancestor" is, _this_ is left to science. To solve these questions, = we need=20 > a > phylogeny -- that is, a phylogenetic _hypothesis_, a phylogenetic t= ree, to > which we can _apply_ the nomenclature. Making and disproving phylog= enetic > hypotheses is the job of the science of phylogenetics. Being a scie= nce, it > does not make definitions; it applies them. > > * Well, it's not, because the PhyloCode is not yet in effect. > >> We still haven't completed figuring out every last piece of geneti= c >> information on that question. > > If we had, we'd have a very good understanding of phylogeny. But th= is is=20 > not > needed for phylogenetic _nomenclature_. The very idea of phylogenet= ic > nomenclature is that the resulting names should be applicable to _e= very_ > imaginable phylogenetic tree. > >> You can say that a spider scientifically is not an insect. >> You cannot say a dog is an insect. > > These are (or at least could be) examples of applications of phylog= enetic > definitions to a particular phylogenetic hypothesis. :-) > >> Words have to be viable. PhyloCode cannot fully win in science if = all it >> has conquered are the scientists. > > Here I agree. The makers of definitions must think through the pote= ntial > consequences of the definitions they want to coin. There are severa= l rules > and recommendations in the current draft of the PhyloCode that are= =20 > concerned > with this. As I've mentioned, some of those can already be interpre= ted as > not allowing the currently (in narrow circles) "popular" definition= of > Reptilia.=20