Consensus (was: Google for Internet Database of all life...)
kinman2 at YAHOO.COM
Wed Mar 22 21:54:26 CST 2006
It really surprises me that you of all people wouldn't recognize that a paraphyletic Pongidae is inherently more stable than chopping it up and arranging the pieces in every possible cladification possible. One of the results is that we have at least four different concepts of Family Hominidae: (1) Homo and its extinct relatives; (2) Homo + Pan and relatives; (3) Homo + Pan + Gorilla (i.e. African great apes); and (4) Homo + Pan + Gorilla + Pongo (all great apes). Strict cladification has completely destabilized the meaning of both Pongidae and Hominidae. And why? Because Hennig came up with a rule against paraphyly and a bunch of Ivory Tower types spread the practice to their students and anyone else who would listen (and increasingly penalize those who resisted). So if you write to a museum asking for material of Pongidae or Hominidae these days, you'd better clarify exactly what you mean.
I'd be the first to admit cladistic analysis has worked wonders (when done well), but a blind adherence to strict cladism has prevented those advances from being reflected in classifications in a relatively stable, useful fashion. Abandoning a paraphyletic Pongidae, or Amphibia, or Reptilia (etc.) has done nothing but cause more and more confusion. Cladification is sort of like water----we obviously need it, but too much of it and it drowns you. Hennig did not think though the long term implications of his total ban on paraphyly, and neither have those who have followed suit. Where paraphyletic classifications are inherently more stable and useful, I still use them. Hey, I think even the Encyclopaedia Britannica still uses the paraphyletic Family Pongidae (for great apes, minus hominids), so I still have plenty of company on this.
John Grehan wrote:
There is nothing inherently more stable in a paraphyletic classification than any other. If the phylogenetic arrangement is stable then the taxonomic units would be stable - whether mono or paraphyletic. I understand the goal of cladistics is to achieve natural classifications
- at least in theory. In that respect cladistics is at no greater necessary disadvantage than any other approach (not that cladistic theory is necessarily the last word on phylogeny).
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