aff. bff. cff. dff. ...

John McNeill rom!john at ZOO.TORONTO.EDU
Sat Nov 13 18:34:27 CST 1993

> I don't know what a "phylogeny fight" is, but I'm sure it would be
> unpleasant to get into one with John McNeill.

Friendly debate would have been better but less alliterative.  I was only
thinking that, whereas evolutionary divergence is the major process
permitting the recognition both of that grouping of organisms that we call
species and of our "higher taxa", it is not the only one (e.g. alloploidy
in the former case, and possibly analogous hybridization- or
symbiosis-related phenomena in the latter).  Hence I would still to-day
stand by most of what I wrote on "Purposeful phenetics" in 1979 (Syst.
Zool. 28) - however essential cladistic methodology is in understanding
relationships between organisms, the most useful classification may not
necessarily be an exact representation of the phylogeny of the organisms
(particularly if this is held to preclude the recognition of paraphyletic

> I have nothing against morphologic data (I pay what some would say was
> inordinate attention to the details of snail reproductive plumbing, and
> have never sequenced a base-pair in my life).  It is what one does with
> the data that determines results.

I couldn't agree more.

>                                    And there are more ideas floating
> around now about what one should _do_ than at any previous time, making
> unqualified statements of "relationship" or "affinity" less than helpful.

With this I cannot agree.  I am assuming that the judgement of
"relationship" or "affinity" is not based on mere superficial appearance
but is achieved by looking closely at, say, the minute "plumbing
morphology" of the organism (or other features known to be genetically
controlled).  Of course, a well-documented analysis is ideal, but I would
rather have an indication of possible evolutionary relationship than no
comment at all.

But your earlier comments related to editing accounts submitted for
publication - I am with you 100% in demanding in that context that authors
define exactly what they mean by such imprecise terms as "related to" - and
yes, of course, "aff." was created long before systematists realised that
overall similarity and similarity reflecting evolutionary lineages were not
the same - a 1912 paper on Angiosperms by Wernham is the earliest of which
I am aware, but I am not a student of Hennig's antecedents.

I should not log in at home at the weekend - I write too much that is too

John McNeill

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