Explanations and morphology

[Don.Colless at CSIRO.AU]

Richard's commment seems to suggest that "neutral" mutations will be less affected by "convergence". Insofar as they are different, this doesn't apply - or only applies slightly - to "parallelism". I have a programme for "evolving" taxa -  actually, models of haploid genomes - on a random basis. It can allow for various phenomena, such as selection pressure, evolutionary stasis, etc.; but "real" and estimated phylogenies always showed considerable parallelism - around the 15-20% commonly found with real morphological data. I had to increase the number of characters enormously to reduce this. I suspect that there is a simple statistical explanation.

Don Colless,
Div of Entomology, CSIRO,
GPO Box 1700,
Canberra. 2601.
Email: don.colless at csiro.au
Tuz li munz est miens envirun


-----Original Message-----
From:   Taxacom Discussion List on behalf of Richard.Zander at MOBOT.ORG
Sent:   Sun 2/26/2006 3:24 AM
To:     TAXACOM at LISTSERV.NHM.KU.EDU
Cc:	
Subject:             Explanations and morphology
I was just thinking about explanations, particularly J. Grehan's discounting
them. Sure, theory is the basis of science, but John is right that
explanations can be rather empty.

Try this: according to theory, molecular systematics depends on (mostly)
neutral mutations, so it is an independent check on morphological
systematics, which reflects massive convergence.