[Taxacom] Evolutionary misconceptions (was: Ladderisingphylogenetic trees)

[David Wagner]

Jim,

I have to give you a thumbs up here. My view, like yours, is that  
death is too often ignored. What drives (most) evolution is, as Darwin  
taught us, natural selection.  This means not just the best doing all  
the procreating, but the less adapted dying out. Phylogenetics is  
great at figuring out what lineages have been selected for, the good  
procreators, but it has theoretical problems about dealing with the  
discontinuities caused by failure to be selected. These failures to be  
selected are what result in the evolutionary gaps between lineages  
that separate species.

And we mustn't forget that natural selection is just as likely to act  
on plesiomorphies as apomorphies. It will select for no change in  
stable environments just as it will select for new adaptations in a  
changing environment. Or new environments encountered as the  
geographic range of a successfully procreating lineage expands,  
leaving a stable and unchanging population behind.

David


David H. Wagner, Ph.D.
Northwest Botanical Institute
P.O. Box 30064
Eugene, OR 97403-1064

davidwagner at mac.com
541-344-3327

http://web.mac.com/davidwagner/Site/FernZenMosses.html

On Mar 11, 2010, at 6:59 PM, Jim Croft wrote:

> I am a negative-space kinda guy (also some would claim, a negative,
> space-kinda guy)... speciation happens not with reproduction, but
> with death - the joining bits in the middle die out.. et voila!  
> species
> happens.  :)
>
> It is death, not birth that holds all the good cards...
>
> building biodiversity - one death at at time... :)
>
> jim
>