Number games (was: Apology...)
Ken Kinman
kinman2 at YAHOO.COM
Thu Apr 15 21:23:52 CDT 2004
John Grehan wrote:
Ken commented a while back (if I recall this correctly_ that he was against competing phylogenies simply on the basis of one having more characters than another). How does this translate to his support for molecular techniques that would seem to be influenced by the same factor?
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To which I respond:
My approach to molecular evidence is not all that different from morphological evidence. Something simple like a single base change doesn't carry much weight in my mind. Just two unusual indels (of 5 bases each) may convince me more than fifty individual base changes scattered in a variable region. That is why I don't particularly trust "most parsimonious" trees. The true tree could be many steps longer depending on the way in which characters are selected (and weighted or not weighted).
And a tree based on John's orangutan database would undoubtedly show a Pongo-human clade as being most parsimonious. But without any molecular data at all, I wouldn't trust it. I like to look at a wider picture and not just one scientist's biased database. And let's be realistic, they are all biased to some extent---that is just human nature.
---------- Ken Kinman
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