[Taxacom] Hypothesis: How Nothofagus rafted to New Zealand

[Frederick W. Schueler]

Curtis Clark wrote:
> On 2006-12-23 20:03, Ken Kinman wrote:
>>     My hypothesis is that one (or more) Nothofagus cunninghamii trees 
>> rafted to New Zealand carrying on their branchs both their own fruit and 
>> their unique fungus Cyttaria gunni.  The tree or trees could have been 
>> dislodged due to land slides, massive floods, or even a tsunami---pick 
>> your favorite disaster.
> 
> This is not a hypothesis, since it's not testable. It's evolutionary 
> "tall tales" such as this that give the panbiogeographers ammunition.

* isn't this the crux of the dispersalist/vicariantist 
(panbiogeographer/Darwinian) discussion: does one rule out dispersal 
events of low but finite probability, just because it's hard to 
corroborate their historical occurrence?

Ken does suggest a test for his "emergent drift" hypothesis: "look into 
mosses and insects... No telling what all a floating tree could have 
carried over." Maybe the biogeographer's job is to understand how those 
low annual probabilities add up over millions of years, and how they 
affect other events of higher intrinsic probability?

fred.
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