Bill Burnett (
Mon, 6 Nov 1995 10:24:12

In article <47dcev$> writes:

> (Ludvig Mortberg) wrote:
>Did I say that molecular
>>systematics has priority over other methods in systematics? Well it
>>has. Why? Because it's very sophisticated technically. A

>Well, this is a hard question. I think the important thing is that molecular
>systematics gives you
>a number that is unquestionably free from any biased human opinion. Some people
>do argue that
>rates of neutral mutation aren't constant etc. but there's still going to be
>more genetic change
>between distantly related species.

>Also, the 5-8 million year ago split is compatible with the fossil data, isn't

>James Borrett.

Hmmmm, keep working on that irony detector, James. :-)
In all seriousness though, bear in mind that molecular data sets can be
fraught with problems too... it's great that we have unambiguous base calls
for characters but bias can be introduced at later stages by the particular
analysis you choose.... there's also things like repeat hits to consider,
especially in fast evolving molecules, and also tertiary structures in things
like rRNA sequences. I'm a big fan of sequence data (or I'd feel like a
waste of space...) but there's no reason to suppose a good
morphologically based phylogeny is 'worse' than a good molecular one.
Personally, if they contradict one another I go look for more data.